Golshid Hadialhejazi - Mark- och vattenteknik - KTH

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22© Golshid Hadialhejazi 2012Degree Project for the master program in Environmental Engineering and SustainableInfrastructureDepartment of Land and Water Resources EngineeringRoyal Institute of Technology (KTH)SE-100 44 STOCKHOLM, SwedenReference to this publication should be written as: Hadialhejazi, G (2012) “Assessment ofvanadium sorption by different soils” TRITA LWR Degree Project 12:22ii

Assessment of vanadium sorption by different soilsبه مادرم،‏به پدرمiii

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22iv

Assessment of vanadium sorption by different soilsSUMMARY IN SWEDISHVanadin är en ljus metall som hör till grupp 5 i det periodiska systemet.Den kan existera i olika oxidationstillstånd från -2 till 5, även om deredoxformer kan hittas naturligt i miljön är (III), (IV) och (V). Eftersomvanadin är giftigt vid höga koncentrationer, och då vanadin är en vanligförorening från t.ex. metallurgiska slagger, behövs mer detaljeradkunskap om vanadins miljöegenskaper. En viktig sådan egenskap är desssorption till jordmaterial, eftersom detta kommer att avgörabiotillgänglighet och risk för läckage från mark till grund- och ytvatten. Iytliga jordhorisonter är vanadin(V) ofta en dominerande redoxformen avvanadin. Syftet med denna studie var därför att bestämma sorptionen avvanadin(V) till 7 olika jordar samt att undersöka de faktorer, t.ex. pH,som avgör sorptionen.På laboratoriet har sorptionen av vanadin(V) studerats som en funktionav pH, vanadin(V) koncentration, och fosforstatus. De olika jordarnasförmåga att adsorbera vanadin(V) jämfördes på grundval avFreundlichekvationens parametrar m och log Kf. Det visade sig attjordens lerhalt samt innehållet av oxalatlösligt järn och aluminium var tvåviktiga faktorer. Ju högre värden för dessa jordegenskaper, desto störreblev vanadin(V)-sorptionen. Av de jordar som undersöktes varsorptionen starkast i Kungsängen A3, och den sjönk sedan i följandeordning: Säby, Kungsängen D3, Pustnäs, Termunck, Guadalajara ochZwijnaarde. Det bör noteras att de tre jordar med starkast vanadin(V)-sorption samtliga var lerjordar, medan de fyra andra jordarna varutvecklade i sand eller silt.pH-beroendet för vanadin(V)-sorptionen bestämdes också. Resultatenvisar att den procentuella mängden sorberat vanadin(V) ökar medminskande pH. Detta beror förmodligen på att vanadin(V) förekommersom en anjon (d.v.s. vanadat) och att man får en ökad positiv ytladdningpå jordens partikelytor vid lägre pH-värden. Vidare konkurrerar fosfatoch vanadin(V) med varandra för bindning till jordens ytgrupper; därförorsakar en ökad fosforhalt en minskande vanadin(V)-sorption i marken.Alltså är både pH-värdet och fosforstatusen två ytterligare faktorer sompåverkar jordars förmåga att binda vanadin.v

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22vi

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22x

Assessment of vanadium sorption by different soilsABBREVIATIONS AND SYMBOLSAlBFBOFCa 2+CaCO 3Ca(OH) 2CO 2CO 32-EAFFeHNO 3IAPICP-OESK fK smMnn addn initn sobNaNO 3NaOHNaVO 3PpK aPO 4-PV+VO 2VO 2+V 2O 5AluminumBlast FurnaceBasic Oxygen FurnaceCalcium ionCalcium carbonateCalcium hydroxideCarbon dioxideCarbonate ionElectric Arc FurnaceIronNitric acidIon Activity ProductInductively coupled plasma- optical emissionspectroscopyFreundlich coefficientSolubility constantNon ideality parameterManganeseAdded V ionsInitial V boundTotal sorbed vanadiumSodium nitrateSodium hydroxideSodium metavanadatephosphateAcidity constantOrthophosphate PhosphorusVanadiumdioxovanadiumoxovanadium/vanadylVanadium pentoxidexi

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22xii

Assessment of vanadium sorption by different soilsABSTRACTVanadium is a white bright metal that belongs to group 5 in the periodic table ofelements. It can exist in different oxidation states from -2 to +5 although the formscan be found naturally in the environment are (III), (IV) and (V). As vanadium is toxicat high concentrations, and as vanadium is a common contaminant from e.g., steelslags, more detailed knowledge on the environmental behavior of this metal isrequired. One important property is its sorption to soils, as this will determine thebioavailability and the risk of leaching from soils. In surface soils vanadium(V) iscommonly the predominating redox species. Therefore the purpose of this study wasto determine vanadium(V) sorption in 7 different soils in order to investigate thefactors determining vanadium(V) sorption and to estimate the capacity of the soils tobind vanadium.From laboratory adsorption experiments, vanadium sorption has been studied as afunction of pH, vanadium(V) concentration, and phosphorus status. The adsorbedvanadium(V) of investigated soils was compared on the basis of the Freundlichparameters m and log K f. The clay content of the soil and the content of oxalatesoluble iron and aluminum were two important factors for the vanadium(V) sorptionbehavior. The higher the values of these soil properties, the stronger was vanadium(V)sorption. Among the soils investigated here the sorption strength was highest for theKungängen A 3 soil and then decreased in the following order Säby, Kungsängen D 3,Pustnäs, Termunck, Guadalajara and Zwijnaarde. It is notable that the three soils withthe strongest vanadium(V) sorption were clay soils, whereas the other four were sandyor silty soils.The pH dependence of vanadium sorption was also determined. The results show thatthe percentage sorbed vanadium(V) increases with decreasing pH. This is dueprobably to the anion properties of vanadium(V) (i.e. vanadate) in combination withincreased positive surface charge on the soil colloids at lower pH. Moreover there is acompetition between phosphate and vanadium(V) for sorption sites, which will causeless vanadium(V) sorption in soils. Therefore both the pH value and the phosphorusstatus are two additional factors that influence the vanadium sorption properties ofsoils.Key words: Vanadium, soil, Freundlich model, sorption1. INTRODUCTIONVanadium was first discovered by Andrés Manuel del Rio, a Mexicanchemist, in 1801. But when he sent a sample of vanadium with a paperof its description to Institute de France in Paris for analysis andconfirmation, the paper got lost on the way to France so the institutedeclared that the sample contained nothing but lead chromate.Vanadium was then rediscovered by Nils Gabriel Sefström, a Swedishchemist, in 1830.1.1. Vanadium chemistryVanadium is a bright white metal belonging to group 5 in the periodictable of elements (Fig. 1), with the symbol of V (WHO, 2000). Its atomicnumber is 23, the atomic weight is 50.942 (g/mol), the melting point is1887 the boiling point is 3337 and its phase at room temperature issolid (Mitchell, 2000).1

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22Fig. 1. Periodic table of the elements.Vanadium has good corrosion resistance to alkalis, sulphuric acid andsalt water. It can exist in different oxidation states from -2 to +5although the forms that can be found naturally in the environment are(III), (IV) and (V).The metal oxidizes readily above 660 to form V 2O 5.Also vanadium(IV) and (V) can go through complex hydration reactionsthat led to multitude of compounds (Nriagu, 1998).Vanadium has different isotopes which mean that the vanadium atomshave different number of neutrons. Table 1 illustrates some isotopes ofvanadium and their half-life (Nriagu, 1998).1.2. Vanadium productionThere are only few ores from which vanadium can be extracted as asingle product. Otherwise most of the vanadium comes as byproductsfrom the extraction of other elements such as iron, phosphorus anduranium. Ores from which vanadium can be extracted are located inAfrica and North America (about one third of vanadium resources) andabout 24% are found in Europe and less than 4% are located in Asia andSouth America. About 46 million tons of vanadium is in iron ores, 8.5million tons in crude oil and tar sands and 7.5 million tons in phosphaterocks (Nriagu, 1998).Regardless of how the vanadium has been produced (primary ore, as aby-product or in petroleum) the principal starting material forproduction of all vanadium compounds is V 2O 5 (Nriagu, 1998).Table 1 - Vanadium isotopes and their half-life.IsotopeHalf-lifeV-48 15.98 daysV-49 337.0 daysV-50 1.4x10 17 yearsV-51 StableV-52 3.76 minutes2

Assessment of vanadium sorption by different soils1.3. Vanadium usage1.3.1. Metallurgical usageVanadium is the seventeenth most common element in the earth’s crustand is mostly combined with other metals to make special metal mixturecalled alloys (Mitchell). Because of the high strength to weight ratio,excellent load-bearing characteristics and altering the formability of thesteels containing small amounts of vanadium, such alloys have been usedin construction of trains, automobiles and aircrafts (Nriagu, 1998).Approximately 85% of vanadium is used in steel industry. Another 10%is used as an essential alloying element for titanium (CEC, 2011).1.3.2. Therapeutic usesThe other usage of vanadium is in therapeutic agents; typically vanadiumwas used as an antiseptic on the skin and on mucous membrane of thebladder, vagina and the uterine canal (Nriagu, 1998). It also has a widevariety of insulin like effects which make it a candidate for oral therapyin diabetes (Marzban & McNeill, 2003).1.3.3. Use in pigmentsVanadium compounds show a wide range of hues from yellow to greenand from red to black. This feature of vanadium causes vanadium saltsto be used in dyeing of cotton and viscose rayon and for fixing anilineblack on silk. Also ammonium metavanadate is used as color enhancer inceramic glazes (Nriagu, 1998).1.3.4. Use as catalystThe efficiency of the use of vanadium as catalyst is not only because ofbeing much cheaper than other catalyst but also it is insensitive to manyof the platinum poisons encountered in sulfuric acid manufacture(Nriagu, 1998).1.4. Background of environmental emission of VIt has been estimated that about 65 000 tons of vanadium enter theenvironment from natural sources per year and around 200 000 tons as aresult of anthropogenic activities which is mostly because of atmosphericemissions of metallurgical works followed by combustion of fossil fueland in limited areas from steel industry (WHO, 2000).In soil vanadium is associated with iron oxide, argillaceous minerals andwith the organic fraction. The average amount of vanadium in soil rangesfrom 10 to 20 ppm. Limestone soils contain the most and peat-soilscontain the least. Soils from industrial areas can have more vanadiumdue to anthropogenic activities (Poledniok & Buhl, 2003).Vanadium in rocks and soils does not form its own minerals nor it doesnot exist as free metal but it presents as vanadate of copper, zinc, lead,uranium, ferric iron, calcium, manganese and potassium. Moreover,vanadium has a tendency to replace other metals such as iron, aluminumand titanium in crystal structures. Weathering increases the availability ofthe vanadium in soils by decomposing parent rocks. Vanadium(V) ismore soluble so it is more mobile than vanadium(IV), and vanadium(III)is the least mobile form. Vanadium’s mobility generally increases inalkaline soils. However also at lower pH, under certain conditions thecationic forms of vanadium (V 3+ , VO 2+ ) may be mobilized as complexeswith humic or fulvic acid. Vanadium(V) as vanadate is mobile in soils athigher pH and is relatively more toxic to soil microbiota (Environment,2005).3

Golshid Hadialhejazi TRITA-LWR Degree Project 12:221.5. Health effects of vanadiumWhile the functional role of vanadium in the body tissues has not beenconfirmed yet some scientists support the concept that vanadium may beessential for animals (Domingo, 1996). Lack of vanadium may causegrowth reduction. It is also an important factor in soil nitrogen fixingmicroorganisms; moreover it may play an important role in humannutrition (WHO, 2000).The degree of the vanadium toxicity depends on different factors such asthe oxidation state of vanadium, the chemical form of the specificvanadium compound, the route of exposure and the period of dosing aswell as the dose of vanadium administered (Domingo, 1996).1.5.1. AnimalsToxicity of vanadium has been found to be high when it is givenparenterally, low when it is orally administrated and in the case ofrespiratory exposure it is intermediate. Toxicity is related to the valanceof the vanadium compound, which becomes more toxic in highervalance. Plus vanadium is toxic in both cation and anion forms. Severeacute exposure is the reason of systematic effects. Most frequent findingsin animals were in the liver, kidney, gonads and the nervous systems.Though systematic effects at very low level of exposure are reported(WHO, 2000).Vanadium(V) and vanadium(IV) may cause adverse effects in mammals,depending on the circulating vanadium levels. Loss of body weight,toxicity, morbidity and even death were found following vanadiumexposure.1.5.2. PlantsPlants can accumulate trace elements in their tissues due to their abilityto adapt to variable chemical effects of the environment, so plants areintermediate reservoirs of the trace elements derived from lithosphere,atmosphere and hydrosphere (Varga et al., 1999). Vanadium absorptionby plants depends on the soil type (Gill et al., 1995).A study on the effect of cadmium, lead, nickel and vanadium on theuptake and transport process in cucumbers showed that theaccumulation and the transport rate of vanadium is the lowest one incomparison with other elements (Varga et al., 1999). Studies show thatmost of the vanadium that enters the plant remains in roots and a smallamount goes to leaves (Kaplan et al., 1989). Toxicity signs in the rootsare color darkening, club shape of the main roots, reduction ofsecondary root number and reduction of the root’s length. After a longperiod of time V toxicity will cause necrosis and root death (Gill et al.,1995).V addition to nutrient solutions had an impressive effect on bothnutrient balance and biomass of soybean plants (Kaplan et al., 1989).Vanadium in tomato plants make easier absorption of the iron whereasin bush bean Manganese absorption become easier (Gill et al., 1995).1.6. SlagsIn different processes of the steel industry, slags (byproduct of steelindustry) are produced. According to the definition of Ziemkiewicz(1998) “slag is nearly any solid which melts and forms a silicate glassduring a metal refining process”. Slags contain high level of metals suchas iron, chromium and vanadium. The properties of the slags depend onthe raw material used and the manufacturing process. There are threedifferent types of steel industry slags, each named for the process from4

Assessment of vanadium sorption by different soilsFig. 2. Oxidation state of vanadium species as a function of pHand redox potential (versus standard hydrogen electrode) fordilute vanadium solution at 25°C (Crans & Tracey, 1998).which it is produced; Blast Furnace (BF) iron slag, Basic Oxygen Furnace(BOF) steel slag and Electric Arc Furnace (EAF) steel slag. BFs are usedfor iron production while BOF and EAF are used for steel production(Proctor et al., 2000).Steel slags are glasses so in its coarser form it will compact and maintainhigh permeability regardless of how much water has passed throw it.Also steel slags do not absorb CO 2 from the air and convert back tomoderately insoluble limestone: (Ziemkiewicz, 1998) Equation 1This is a very important property since it means that we can leave theslag in the open air for years and still get high level of alkalinity(Ziemkiewicz, 1998).The concentration of the leaching of vanadium from slags is not directlyrelated to its concentration. It mostly determined by environmentalconditions and physical and chemical properties of the slags. Studiesshow that acidic conditions will increase V leaching (Chaurand et al.,2007).Experiments on steel slags by Chaurand et al. (2006) revealed thatvanadium is predominantly present in the 4+ oxidation state in steelslags. It also indicates that the average oxidation state of vanadium inBOF slag reduces during leaching at pH 5. So during natural ageing Voxidizes to its pentavalent form (Chaurand et al., 2007).Slags from steel industry are valuable materials and can be reused asconstruction applications, e.g in roads, pavements or for dense liners in alandfill base or cover construction. The reuse of the slags avoidslandfilling of those materials and reducing both cost and exploration ofnatural raw materials for construction purposes (Diener et al., 2007).There are also declared targets for reusing slags (Motz & Geiseler, 2001).1. Protection of the environment and improving its quality2. Human health protection3. To guarantee a careful and efficient use of the environment5

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22For many years, in northern Sweden, slags of the steel manufacturingindustry were used as a fertilizer for a farm. In October 1989 in one casethe slags were not ploughed in and just laid on the surface. During a 10-day period 23 heifers out of 98 cattle died of acute vanadium toxicity.The accumulated concentration of vanadium was found in the liver,kidney, spleen and urine of the cattle (Frank et al., 1996).1.7. Redox chemistry of vanadiumAs mentioned before there are different oxidation states for vanadiumcompounds, three of which, vanadium(III), (IV) and (V) exist inbiological and environmental systems.The oxidation state 5 (V) is the most common one under mostenvironmental conditions (Fig. 2) while oxidation state 4 exists underacidic conditions (Nriagu, 1998). At the boundary lines of figure 2,species are present in equal concentrations. Boundaries shown by shortdashes are less certain than those shown by bold lines. The upper andlower longer dashes lines illustrate the upper and lower limits of stabilityof water (Crans & Tracey, 1998).1.7.1. Vanadium(V)Vanadium(V) is the most mobile form of the vanadium in different pHranges; it is also the most common form of vanadium under oxicconditions and pH values above four. Vanadium(V) undergoeshydrolytic reactions in water, will produce different anionic species suchas vanadate. Vanadate also forms a wide range of condensed oligomericforms, while each of them exist in different protonation states;moreover, at low pH vanadium(V) complexed to ligands exists as cationVO + 2 (Nriagu, 1998).Under acidic conditions, with pH values ranging from 3 to 6, thepredominant oligomer is decavanadate, V 10O 6- 28 which is abbreviated toV 10. This complex anion is the major vanadium oxidation which hascolor that forms yellow-orange solutions.From pH 6 to 10 the major oligomers are dimer (V 2), cyclic tetramer (V 4)and cyclic pentamer (V 5) which are all colorless. Below pH 3 the cationicmonomer is the major species whereas above pH 10 the anionicmonomer is the favored species.Fig. 3. Aqueous structure for the deprotonated majoroxovanadium(V) ions (Crans & Tracey, 1998).6

Assessment of vanadium sorption by different soilsFig. 4. Percentage concentration of oligomers and monomers atdifferent concentrations of vanadate in pH 4.When obtaining colored solutions heating is often necessary in order toconvert the hydrolytically more resistant V 10 to colorless oxoanions(Crans & Tracey, 1998).The equilibrium of the colorless vanadium(V) species in solution isextremely sensitive to vanadium concentration, pH, ionic strength andother solution components such as potentials (Nriagu, 1998).It should be taken into account that the mentioned oligomers (Fig. 3)only appear in high concentration of vanadium. The percentage of totalconcentration oligomers and monomers for different concentrations ofvanadate shows that by increasing the concentration of vanadate from10 -6 molal to 1 molal, there will be a higher concentration of oligomersand lower concentration of monomers. Comparison between the totalconcentration of oligomers and monomers in different concentrations ofvanadate (molal) in pH 4 (Fig. 4) and pH 6 (Fig. 5) shows that byincreasing pH to pH=6 oligomers will appear in higher concentration ofvanadate in comparison with lower pH (pH = 4).Fig. 5. Percentage concentration of oligomers and monomers atdifferent concentrations of vanadate in pH 6.7

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22Fig. 6. Hydrated structure for VO 2+ : [VO(H 2O) 52+] and[VO(OH)(H 2O) 4+ ] (Crans & Tracey, 1998).1.7.2. Vanadium(IV)Vanadium(IV) is formed from vanadium(V) in the presence of anyreducing component in the aqueous solution. Vanadium(IV) is found attrace levels in mammals and living humans (Nriagu, 1998).Dissolution of VOSO 4 in acidic aqueous solutions causes the hydratedvanadyl cation VO(H 2O) 52+ abbreviated as VO 2+ (Fig. 6) (Crans &Tracey, 1998).1.7.3. Vanadium(III)In nature vanadium(III) is complexed to organic ligands or exists in veryreducing environments. Vanadium(III) containing minerals immediatelybecome oxidized upon leaching from soils. So the fundamental problemthat will occur during study of the aqueous chemistry of vanadium(III) isthe limited pH range and potential, over which this oxidation state isstable (Crans & Tracey, 1998).The deprotonation of the monomeric species [V(H 2O) 6] 3+ and[V(OH)(H 2O) 5] 2+ (Fig. 7) appears when the pK a values are about 2.6 and4.2 respectively.1.8. Objective of the studyThe aim of this study is to determine the adsorption of vanadium(V) todifferent soil types, as a function of the pH value, vanadium(V)concentration and phosphorus status.Fig. 7. Hydrated structure for V(III): [V(H2O) 63+],[V(OH)(H 2O) 52+] and [V(OH) 2(H 2O) 4+ ] (Crans & Tracey,1998).8

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22Fig. 8. Field plan for sampling Kungsängen soils.2.2. ExperimentsAfter sampling and preparation of all the soils, laboratory experimentswere carried out. The soil sample (2 g) was placed in centrifuge bottlesmarked from 1 to 48 for each soil. Then deionized water was added tothe soils, the amount of deionized water was 30 ml minus the additionsof NaNO 3, HNO 3, NaOH and NaVO 3. 10 ml of 0.03 M NaNO 3 wasadded to obtain an ionic strength of approximately 0.01 M in all systems.The amount of 0.03 M HNO 3 or 0.03 M NaOH added was varied toobtain a range of pH values after equilibrium (see appendix for detail).The addition of NaVO 3 was made by adding 1 ml of 1.5 mM NaVO 3 formost of the samples except for the isotherm samples where a range ofmetavanadate concentrations was added. (Appendix 1-5)After adding all the solutions to the soils the centrifuge tubes wereplaced in the racks and were shaken for 6 days in an end-over-end shakerat room temperature to reach equilibrium. After 6 days of equilibrationthe suspended matter was removed from the suspension bycentrifugation at 3000 rpm for 20 minutes. The pH value was measuredby removing 5 ml of supernatant from each bottle to a pH measurementbottle by a pH meter using a radiometer combination electrode. Theseparated solution was filtered by 0.8/0.2 µm Acrodisc PF syringe filtersto 20 ml scintillation bottles. (The additions of solutions to each samplecan be seen in the appendix, table 1 to 5) After filtration, PO 4-P wasmeasured for all 5 soils on FIA Aquatec.FIA Aquatec is an instrument for analysis of phosphate, nitrate andammonium in water and aqueous samples such as soil extracts. Forphosphate, the acid molybdate method is used and PO 4-P is determinedspectrophotometrically at 880 nm.Analysis of vanadium, calcium and aluminum is done by Varian VistaPro Ax ICP-OES. Before the analysis, samples were acidified by adding30 % ultrapure HNO 3 to reach a concentration of 1% HNO 3 in eachsample. By definition of Perkin Elmer “the inductively coupled plasma(ICP) is argon plasma maintained by the interaction of an RF field andionized argon gas.” There are different types of ICP from which ICP-OES was chosen to be used in this project. ICP optical emissionspectroscopy (ICP-OES) is the measurement of the light emitted fromthe elements in the sample inserted into an ICP source (Perkin-Elmer,2009)To interpret vanadium(V) sorption data, the freundlich equation wasused in this work. In principle the adsorbed concentration of vanadiumcan be calculated from the Freundlich equation by getting the dissolvedconcentration of vanadium from the results of ICP-OES. TheFig. 9. Plottedcircle forsampling.10

Assessment of vanadium sorption by different soilsmLog nFig. 10. Freundlichequation’s graph.Log K FLog cFreundlich model is as equation 2: Equation 2where n is the amount of sorbed vanadium in all samples. c is theconcentration at equilibrium, which is in mol/l. K f is the Freundlichcoefficient which is the intercept and m is the slope (Fig. 10). n is the sumof two contributions, i.e. n = n sorb + n init, where n sorb is the sorbed V inthe experiment. The value of n sorb is calculated by subtracting theconcentration of the dissolved vanadium from the added vanadium inmol/kg. On the other hand n init is the initial amount of vanadium in thesoil in mol/kg.Equation 2 can also be written as: Equation 3The logarithmic equation (Eq. 3) was used to plot a graph of log n versuslog c (Fig. 10). But it should be taken into account that before addingvanadium to the samples there was a certain amount of V that wasbound to the soils. So the equation 2 was rewritten as; Equation 4Where n add is the amount of vanadium added in the experiment in mol/land n diss is the dissolved concentration of vanadium in the experiment inmol/l.The initial V needs to be calculated and the method used here for thiscalculation was the perfect Freundlich method. In this method n init willbe optimized by trial-and-error until the best fit observed. This is doneby first guessing a number for initial V and then the graph for log nversus log c can be calculated. By using the trendline tool in Excel thevalues for the intercept K f and the slope m ware obtained from linearregression, including the r 2 value for the regression line. By trial-anderrorinitial V was changed until the best r 2 value (that is the closest to 1)was obtained.3. RESULTS AND DISCUSSION3.1. pH measurementsThe pH measurement was done by a pH meter using a Radiometercombination electrode. Different soils had different pH values. ForGuadalajara the pH was around 8, while for Termunck it was around 6.5,Zwijnaarde’s pH was around 5.5 and for both Kungsangen soils themeasured pH was around 6.The results for the pH values of the Guadalajara soil are typical forcalcareous soil which means that the soil contains calcium carbonate. Forthese samples, the alkalinity was determined, as carbonate maypotentially compete with vanadate for sorption sites.11

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22Fig. 11. Alkalinity versus pH for Guadalajara.3.2. Alkalinity test and solubility of CaCO 3 for GuadalajaraThe results for the alkalinity determination can be seen in figure 11(Appendix 6).The graph illustrates that there is a relation between pH and alkalinity.By increasing the pH to 8 the alkalinity is decreased. Between pH 8 and9.5 the alkalinity is stabilizes around 0.001 (mEq/L) and at higher pH thealkalinity increases again.By using the data from alkalinity analysis and the measured Ca in ICP-OES runs, we can investigate whether the Guadalajara soil is close tosaturation with respect to calcium carbonate.The solubility equilibrium of the calcite is as equation 3: Equation 5Because the activity of the solid phase is considered to be equal to 1, thesolubility constant K s at 25 o C can be written as equation 4: . Equation 6Fig. 12. Solubility of calcium carbonate in the Guadalajara soil.12

Assessment of vanadium sorption by different soilsFig. 13. Dissolved PO 4-P versus pH for Kungsängen A 3.The graph for the solubility of the calcium carbonate in Guadalajara soil(Fig. 12) shows that there is equilibrium with calcite in this soil at naturalpH and below. But at higher pH (more than 8.5) there is supersaturationbecause the ion activity product (IAP) is larger than K s. Thesupersaturation condition is probably because calcite starts to precipitateunder these conditions and initially an amorphous calcium carbonate,with a higher solubility, will be formed. The red line in the graph isaccording to the solubility equilibrium given in equation 6.3.3. Dissolved phosphorus as a function of pHThe following figures show the dissolved PO 4-P versus pH in twodifferent conditions;• With P addition• Without P additionAfter P addition both Kungsängen D 3 and A 3 still have rather lowdissolved PO 4-P in comparison with other soils. This is probably due tothe high quantity of sorbing surfaces in Kungsängen, i.e. aluminum andiron (hydr)oxides or clay minerals (Fig. 13 & Fig. 14).Fig. 14. Dissolved PO 4-P versus pH for Kungsängen D 3.13

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22Fig. 15. Dissolved PO 4-P versus pH for Zwijnaarde.For Kungsängen A 3 dissolved PO 4-P when no P was added was around50 µg/l. For Kungsängen D 3 this amount is around 200 µg/l, which is 4times higher than dissolved PO 4-P for Kungsängen A 3 (Fig. 13 &Fig. 14). This difference is due to long-term P fertilization inKungsängen D 3.The Zwijnaarde soil is a Haplic Podzol with subsurface accumulation ofiron-aluminum-organic compounds (Tyler, 2004). However, the amountof dissolved P is relatively high compared to Kungsängen (Fig. 15).Termunck is a Haplic Luvisol which is a sandy soil; therefore P sorptionof this soil is expected to be low (Fig. 16) due to the coarse-texture ofthese soils and more inert character of sand particles (Busman et al.,2009). Indeed, dissolved P was high, especially after P addition, whichsupports this hypothesis.In Guadalajara, which is an alkaline soil (soil pH is higher than 7),calcium is the dominant cation which will react with phosphate. Thesequence of calcium and phosphate reactions in alkaline soils is thecreation of amorphous calcium phosphate, octocalcium phosphate, andhydroxyapatite. Formation of Ca-P minerals is more efficient at high pH;therefore less phosphate will be expected to be soluble at high pH. Thistrend is observed only at pH > 9 for the Guadalajara soil, which suggestsFig. 16. Dissolved PO 4-P versus pH for TerMunck.14

Assessment of vanadium sorption by different soilsFig. 17. Dissolved PO 4-P versus pH for Guadalajara.that the conditions for Ca-P formation are not optimal in this soil(Fig. 17).Therefore the sorption of phosphate at natural pH (around 8) willdepend on, for example, the concentration of Al and Fe (hydr)oxides,which is rather low in this soil. Because of this, dissolved P is high afterP addition.As can be seen in the above figures, dissolved phosphate is generallyhigher at higher pH. This is due probably to stronger sorption at low pHbecause of more positive charge on the soil colloids (FeOH and AlOHsurface groups on Fe/Al (hydr) oxides and on clay minerals). ForKungsängen A 3, however, dissolved P did not behave in this way; forthis soil, dissolved P increased slightly with decreasing pH. The reason isnot known, but could be due for example to dissolution of P-sorbingAlOH groups at lower pH.Fig. 18. Vanadium sorption isotherms of the investigated soils.15

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22Table 4 – Optimized K F and m values of the investigated soils.soil K F (l/kg) m n init (mmol/kg)Kungsängen A 3 3.062 0.588 0Kungsängen D 3 3.758 0.626 0Guadalajara 0.670 0.662 0.012Ter Munck 0.803 0.659 0.038Zwijnaarde 0.501 0.697 0.05Pustnäs 0.334 0.547 0.03Säby 0.987 0.515 0.23.1. Vanadium sorptionThe results of the adsorption experiment for the 5 soils of the study plusSäby and Pustnäs shows that the highest sorption is for Kungsängen A 3and after that Säby, Kungsängen D 3, Pustnäs, Termunck, Guadalajaraand Zwijnaarde (Fig. 18). The result is more precise if we compare thevalues for K f and m that were optimized for different soils (Appendix 7).Values for K f and m are given in Table 4. Different types of processes areinvolved in sorption behavior of the soils. For example from themacroscopic point of view soil properties such as soil pH, content oforganic carbon, clay content and content of oxalate soluble Fe or Mn areeffective in sorption behavior of the soils (Gäbler et al., 2009). Values form and K f from the Freundlich model also represent the sorption behaviorof the soils. In general strong sorption is caused by high values for bothm and K f.In this study, the relative sorption strength was determined on the basisof the dissolved vanadium concentration of 1 µmol/l. Under theseconditions, the amount of sorbed vanadium for different soils can becalculated and the results can be seen in Table 5. The strongest sorptionis for Kungsängen A 3 and after that we have Säby, Kungsängen D 3,Pustnäs, Termunck, Guadalajara and Zwijnaarde.As can be seen from Table 5 and Fig. 18, the investigated soils can beseparated into two groups because of the gap between their sorptionstrengths.• First group (strongly V-sorbing soils): Kungsängen A 3, KungsängenD 3 and Säby.• Second group (weakly V-sorbing soils): Termunck, Guadalajara,Zwijnaarde and Pustnäs.In the first group, Kungsängen A 3 has the highest sorption of vanadiumwhich may be due to the high content of both clay and oxalateextractableamount of Fe (24.11 g/kg soil) and Al (5.3 g/kg soil).Table 5 - Concentration of bound vanadium for theinvestigated soils when dissolved V=1 µmol/l.soil K F (l/kg) m c (µmol/l) Log n n (mol/kg)Kungsängen A 3 3.062 0.588 1 -3.042 0.000908Kungsängen D 3 3.758 0.626 1 -3.181 0.000659Guadalajara 0.670 0.662 1 -4.146 7.14E-05Ter Munck 0.803 0.659 1 -4.049 8.93E-05Zwijnaarde 0.501 0.697 1 -4.482 3.3E-05Pustnäs 0.334 0.547 1 -3.758 0.000174Säby 0.987 0.515 1 -3.095 0.00080216

Assessment of vanadium sorption by different soilsFig. 19. Dependence of vanadium sorption on the sum ofoxalate extractable Fe and Al.The dependence of vanadium sorption strength on the sum of oxalateextractable Al and Fe (Fig. 19) shows that there is a correlation betweenvanadium sorption of Kungsängen soil and oxalate-extractable amountof Fe and Al. Also the dependence of vanadium sorption on the claycontent of the soil (Fig. 20) indicates a relationship between the claycontent and vanadium sorption in Kungsängen soils. AlthoughKungsängen D 3 has a high content of clay and oxalate-extractableamount of Fe and Al too, it has a higher amount of phosphorus incomparison with A 3; phosphorus competes with vanadium(V) forsorption sites. After Kungsängen A 3, Säby has the highest sorption ofvanadium. This can be as a result of highest amount of clay (26 %),oxalate Fe (4.4 g/kg soil) and oxalate Al (1.25 g/kg soil) afterKungsängen soils.In the second group, the strongest sorption of vanadium is by thePustnäs soil; on the other hand the weakest sorption of vanadium is byZwijnaarde. The remaining soils, Termunck and Guadalajara areintermediate with respect to vanadium sorption.Fig. 20. Dependence of vanadium sorption on the clay contentof the soils.17

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22Fig. 21. % sorbed vanadium versus pH in Zwijnaarde.3.2. pH dependence of vanadium sorptionAnother way to study the vanadium sorption properties is to quantifypH-dependent sorption.All the graphs show that there is a consistent trend regarding the pHdependenceof sorbed vanadium. The percentage of sorbed vanadiumdecreases with increasing pH. Moreover in all the soils vanadiumsorption is lower in case of P addition. The reason is the competitionbetween vanadium and phosphate for sites.In the Zwijnaarde soil there are some samples that have pH lower than3.5 (Fig. 21). When pH is lower than 3.5, vanadium is less stronglysorbed there are several different explanations for this effect:1. Vanadium may be reduced to vanadium(IV), which occurs as thecation VO 2+ , which is desorbed at lower pH.2. Also if vanadium stays as vanadium(V), a cation may be formed,dioxovanadium(V), VO 2+, which is also desorbed at lower pH.Fig. 22. % sorbed vanadium versus pH in Kungsängen D 3.18

Assessment of vanadium sorption by different soilsFig. 23. %sorbed vanadium versus pH in Kungsängen A 3.3. Some sorbent minerals, above all Al (hydr) oxides, may be dissolvedat lower pH, which causes associated V to be desorbed.The difference between the two cases of P addition and no P addition inZwijnaarde soil is very small. That can be because of the high initial P inthis soil. So by adding P to the soil we will not change the P status muchand consequently we would not get a huge difference in the percentageof the sorbed vanadium.In both Kungsängen D 3 and A 3 there is a gap between the percentagesorbed vanadium in the case of P addition and no P addition (Fig. 22 andFig. 23). This difference is because Kungsängen D 3 contains moreinitially bound P that is able to compare with V for sorption sites.In both Kungsängen soils the percentage of the sorbed vanadium wasvery high, above 95%, which may be due to the clay content and/orcontent of iron and aluminum hydro(oxides).Termunck soil has the normal trend for the sorbed vanadium versus pH(Fig. 24). The percent sorbed vanadium was smaller than in Kungsängenbut higher than in some other soils. Again, as for the Zwijnaarde soil, thehigh initial P status of this soil is probably responsible for the very smalleffect that the extra added P has on vanadium sorption.Fig. 24. % sorbed vanadium versus pH in Termunck.19

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22Fig. 25. % sorbed vanadium versus pH in Guadalajara.In Guadalajara the results for vanadium sorption (Fig. 25) both with Paddition and without P addition were very close to each other, especiallyat high pH (pH 10). The reason is that at high pH, P precipitates ascalcium phosphates, which decreases the level of competition.(Guadalajara is rich in calcium).The above results and discussion can be summed up as:• There is a correlation between clay content of the soil and thedissolved P. In the case of high clay content in soil as in theKungsängen soil, there will be high sorption of P and of course lowdissolved P.• There will be an increase in dissolved vanadium when increasing thepH. That is because at low pH the soil particle surfaces will have ahigher positive charge, which will increase V sorption. The sametrend, although weaker, is present for phosphate with the exceptionof the unfertilized Kungsängen A 3 soil.• There is a relationship between the clay content, oxalate-extractableiron and aluminum of the soil and vanadium sorption. The higheramount of clay content in the soil will cause higher vanadiumsorption. A higher amount of the oxalate-extractable iron andaluminum will cause higher vanadium sorption too, becausevanadium bind to iron and aluminum (hydro)oxides in the soil. Inthe study case vanadium sorption strength of soils are according totable 6;• Phosphate competes with vanadium for sorption sites. This isespecially the case for soils with a low initial P status that are subjectto P addition through, e.g. fertilizer.Table 6 - vanadium sorption strength in different soils.Vanadium sorption strengthsoil1 KungsängenA 32 Säby3 KungsängenD 34 Pustnäs5 Termunck6 Guadalajara7 Zwijnaarde20

Assessment of vanadium sorption by different soils4. CONCLUSIONBy laboratory adsorption experiments and by using the Freundlichsorption isotherm, results for vanadium sorption of different soils wereobtained. The Freundlich parameters m and K f indicate the sorptionstrength of soils. The results of sorption for the investigated soils showthat soils can be divided into two groups according to their sorptionstrength. The first group consists of soils that are rich in clay minerals,oxalate-extractable iron and aluminum, these soils sorb vanadiumstrongly. The soils in this group are the clay soils Kungsängen A 3, Säbyand Kungsängen D 3. The second group consists of the soils with lowervanadium sorption. The highest sorption in this group belongs toPustnäs and the lowest one belongs to Zwijnaarde, the other soils(Termunck and Guadalajara) are intermediate with respect to vanadiumsorption.Important determining factors for V sorption seemed to be the claycontent of the soil and the aluminum and iron oxide content.It was observed that by increasing the pH, the percentage sorbedvanadium will decrease. Moreover by adding phosphate to the soilsvanadium sorption will decrease because of their competition forsorption sites. Then additional determining factors for V sorption werethe pH value and the P status of the soil.21

Assessment of vanadium sorption by different soilsMotz, H & Geiseler, J 2001, 'Products of steel slags an opportunity tosave natural resources', Waste Management, vol 21, no. 3, pp. 285-293.Nriagu, JO 1998, Vanadium in the environment, John Wiley & Sons,Incorporated, New York. 410 pPoledniok, J & Buhl, F 2003, 'Speciation of vanadium in soil', Talanta,vol 59, pp. 1-8.Proctor, DM, Fehling, KA, Shay, EC, Wittenborn, JL, Green, JJ, Avent,C, Bigham, RD, Connolly, M, Lee, B, Shepker, TO & Zak, MA 2000,'Physical and chemical characteristics of blast furnace, basic oxygenfurnace and electric arc furnace steel industry slags', EnvironmentalScience & Technology, vol 34, no. 8, pp. 1576-1582.Tyler, G 2004, 'Vertical distribution of major, minor, and rare elementsin a Haplic Podzol', Geoderma, vol 119, no. 3-4, p. 277–290.Van Gestel, CAM, Ortiz, MD, Borgman, E & Verweij, RA 2011, 'Thebioaccumulation of Molybdenum in the earthworm Eisenia andrei:Influence of soil properties and ageing', Chemosphere, vol 82, no. 11,p. 1614–1619.Varga, A, Garcinuno Martinez, RM, Zaray, G & Fodor, F 1999,'Investigation of effects of cadmium, lead, nickel and vanadiumcontamination on the uptake and transport processes in cucumberplants by TXRF spectrometry', Spectrochimica Acta Part B, vol 54,no. 10, pp. 1455-1462.WHO 2000, 'Air quality guidelines for Europe, World HealthOrganization (WHO), Regional Office for Europe, Copenhagen.no 91Ziemkiewicz, P 1998, 'Steel slag: applications for AMD control',Hazardous Waste Research, Morgantown.OTHER REFERENCESBusman, L, Lamb, J, Randall, G, Rehm, G & Schmitt, M 2009. Universityof Minnesota. [Online] Available at:http://www.extension.umn.edu/distribution/cropsystems/DC6795.html [Accessed 31 January 2012].Perkin-Elmer, 2004. Perkin Elmer. [Online] Perkin Elmer Available at:http://www.perkinelmer.com [Accessed 25 October 2011].Soil nutrient management for Maui county, n.d. University of Hawai atManoa. [Online] Available at:http://www.ctahr.hawaii.edu/mauisoil/c_nutrients02.aspx [Accessed20 January 2012].23

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22APPENDIX 2. RECIPE FOR THE EQUILIBRATION OFVANADIUM WITH THE ZWIJNAARDE SOILsamplenumberH 2O(ml)0.03 MNaNO 3(ml)0.03 MHNO 3(ml)0.03 MNaOH(ml)3 mMNH 2PO 4(ml)0.15 mMNaVO 3(ml)1.5 mMNaVO 3(ml)1 15 10 4 - - - 1 3.32 15 10 4 - - - 1 3.33 16 10 3 - - - 1 3.64 16 10 3 - - - 1 3.585 17 10 2 - - - 1 4.096 17 10 2 - - - 1 4.137 18 10 1 - - - 1 4.818 18 10 1 - - - 1 4.89 18.5 10 0.5 - - - 1 5.2210 18.5 10 0.5 - - - 1 5.2811 18.8 10 0.2 - - - 1 5.5412 18.8 10 0.2 - - - 1 5.5613 19 10 - - - - 1 5.7914 19 10 - - - - 1 5.7815 18.5 10 - 0.5 - - 1 6.2316 18.5 10 - 0.5 - - 1 6.2417 18 10 - 1 - - 1 7.3118 18 10 - 1 - - 1 6.6119 17.5 10 - 1.5 - - 1 6.8820 17.5 10 4 1.5 - - 1 6.8821 13.5 10 4 - 1.5 - 1 3.2522 13.5 10 3 - 1.5 - 1 3.2523 14.5 10 3 - 1.5 - 1 3.2324 14.5 10 2 - 1.5 - 1 3.5425 15.5 10 2 - 1.5 - 1 4.0726 15.5 10 1 - 1.5 - 1 4.0727 16.5 10 1 - 1.5 - 1 4.7628 16.5 10 0.5 - 1.5 - 1 4.8329 17 10 0.5 - 1.5 - 1 5.1230 17 10 0.2 - 1.5 - 1 5.2631 17.3 10 0.2 - 1.5 - 1 5.5732 17.3 10 - - 1.5 - 1 5.5533 17.5 10 - - 1.5 - 1 5.7634 17.5 10 - - 1.5 - 1 5.7735 17 10 - 0.5 1.5 - 1 6.1936 17 10 - 0.5 1.5 - 1 6.2137 16.5 10 - 1 1.5 - 1 6.5838 16.5 10 - 1 1.5 - 1 6.5539 16 10 - 1.5 1.5 - 1 6.8640 16 10 - 1.5 1.5 - 1 6.8641 20 10 - - - - - 5.7342 18 10 - - - 2.5 - 5.7243 19.5 10 - - - - 0.5 5.7544 18.6 10 - - - - 1.4 5.7445 18 10 - - - - 2 5.7546 17 10 - - - - 3 5.7747 16 10 - - - - 4 5.7748 14 10 - - - - 6 5.78pHII

Assessment of vanadium sorption by different soilsAPPENDIX 3. RECIPE FOR EQUILIBRATION OFVANADIUM WITH THE TERMUNCK SOILsamplenumberH 2O(ml)0.03 MNaNO 3(ml)0.03 MHNO 3(ml)0.03 MNaOH(ml)3 mMNH 2PO 4(ml)0.15 mMNaVO 3(ml)1.5 mMNaVO 3(ml)1 15 10 4 - - - 1 4.362 15 10 4 - - - 1 4.353 16 10 3 - - - 1 4.534 16 10 3 - - - 1 4.55 17 10 2 - - - 1 5.526 17 10 2 - - - 1 5.667 18 10 1 - - - 1 6.158 18 10 1 - - - 1 6.069 18.5 10 0.5 - - - 1 6.3510 18.5 10 0.5 - - - 1 6.3611 18.8 10 0.2 - - - 1 6.4412 18.8 10 0.2 - - - 1 6.4413 19 10 - - - - 1 6.6714 19 10 - - - - 1 6.6515 18.5 10 - 0.5 - - 1 7.1516 18.5 10 - 0.5 - - 1 7.0717 18 10 - 1 - - 1 7.4118 18 10 - 1 - - 1 7.2419 17.5 10 - 1.5 - - 1 9.2220 17.5 10 - 1.5 - - 1 7.9621 13.5 10 4 - 1.5 - 1 4.0122 13.5 10 4 - 1.5 - 1 3.9923 14.5 10 3 - 1.5 - 1 4.5624 14.5 10 3 - 1.5 - 1 4.5825 15.5 10 2 - 1.5 - 1 5.1426 15.5 10 2 - 1.5 - 1 5.2527 16.5 10 1 - 1.5 - 1 6.128 16.5 10 1 - 1.5 - 1 6.1129 17 10 0.5 - 1.5 - 1 6.2830 17 10 0.5 - 1.5 - 1 6.331 17.3 10 0.2 - 1.5 - 1 6.432 17.3 10 0.2 - 1.5 - 1 6.4233 17.5 10 - - 1.5 - 1 6.5934 17.5 10 - - 1.5 - 1 6.5935 17 10 - 0.5 1.5 - 1 7.1536 17 10 - 0.5 1.5 - 1 6.9637 16.5 10 - 1 1.5 - 1 7.7338 16.5 10 - 1 1.5 - 1 7.7639 16 10 - 1.5 1.5 - 1 7.6840 16 10 - 1.5 1.5 - 1 8.9241 20 10 - - - - - 6.6542 18 10 - - - 2.5 - 6.643 19.5 10 - - - - 0.5 6.744 18.6 10 - - - - 1.4 6.6845 18 10 - - - - 2 6.6846 17 10 - - - - 3 6.6947 16 10 - - - - 4 6.6948 14 10 - - - - 6 6.72pHIII

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22APPENDIX 4. RECIPE FOR EQUILIBRATION OFVANADIUM WITH THE KUNGSÄNGEN D3 SOILsamplenumberH 2O(ml)0.03 MNaNO 3(ml)0.03 MHNO 3(ml)0.03 MNaOH(ml)3 mMNH 2PO 4(ml)0.15 mMNaVO 3(ml)1.5 mMNaVO 3(ml)1 15 10 4 - - - 1 4.532 15 10 4 - - - 1 4.543 16 10 3 - - - 1 4.914 16 10 3 - - - 1 4.915 17 10 2 - - - 1 5.316 17 10 2 - - - 1 5.357 18 10 1 - - - 1 5.738 18 10 1 - - - 1 5.79 18.5 10 0.5 - - - 1 5.9610 18.5 10 0.5 - - - 1 5.9811 18.8 10 0.2 - - - 1 6.1412 18.8 10 0.2 - - - 1 6.1413 19 10 - - - - 1 6.2214 19 10 - - - - 1 6.2615 18.5 10 - 0.5 - - 1 6.4516 18.5 10 - 0.5 - - 1 6.4717 18 10 - 1 - - 1 6.6518 18 10 - 1 - - 1 6.5919 17.5 10 - 1.5 - - 1 6.8420 17.5 10 - 1.5 - - 1 6.7721 13.5 10 4 - 1.5 - 1 4.5322 13.5 10 3 - 1.5 - 1 4.5623 14.5 10 3 - 1.5 - 1 4.8624 14.5 10 2 - 1.5 - 1 4.8825 15.5 10 2 - 1.5 - 1 5.2426 15.5 10 1 - 1.5 - 1 5.3127 16.5 10 1 - 1.5 - 1 5.7228 16.5 10 0.5 - 1.5 - 1 5.7429 17 10 0.5 - 1.5 - 1 5.9930 17 10 0.2 - 1.5 - 1 631 17.3 10 0.2 - 1.5 - 1 6.1232 17.3 10 - - 1.5 - 1 6.1233 17.5 10 - - 1.5 - 1 6.2434 17.5 10 - - 1.5 - 1 6.2135 17 10 - 0.5 1.5 - 1 6.3836 17 10 - 0.5 1.5 - 1 4.4637 16.5 10 - 1 1.5 - 1 6.6338 16.5 10 - 1 1.5 - 1 6.6539 16 10 - 1.5 1.5 - 1 6.7640 16 10 - 1.5 1.5 - 1 6.7141 20 10 - - - - - 6.2242 18 10 - - - 2.5 - 6.2343 19.5 10 - - - - 0.5 6.1944 18.6 10 - - - - 1.4 6.1945 18 10 - - - - 2 6.246 17 10 - - - - 3 6.1947 16 10 - - - - 4 6.2248 14 10 - - - - 6 6.23pHIV

Assessment of vanadium sorption by different soilsAPPENDIX 5. RECIPE FOR EQUILIBRATION OF VANAIUMFOR THE KUNGSÄNGEN A3 SOILsamplenumberH 2O(ml)0.03 MNaNO 3(ml)0.03 MHNO 3(ml)0.03 MNaOH(ml)3 mMNH 2PO 4(ml)0.15 mMNaVO 3(ml)1.5 mMNaVO 3(ml)1 15 10 4 - - - 1 4.532 15 10 4 - - - 1 4.553 16 10 3 - - - 1 4.874 16 10 3 - - - 1 4.915 17 10 2 - - - 1 5.216 17 10 2 - - - 1 5.277 18 10 1 - - - 1 5.658 18 10 1 - - - 1 5.689 18.5 10 0.5 - - - 1 5.8610 18.5 10 0.5 - - - 1 5.8511 18.8 10 0.2 - - - 1 6.0112 18.8 10 0.2 - - - 1 613 19 10 - - - - 1 6.0814 19 10 - - - - 1 6.1415 18.5 10 - 0.5 - - 1 6.316 18.5 10 - 0.5 - - 1 6.3117 18 10 - 1 - - 1 6.4818 18 10 - 1 - - 1 6.4619 17.5 10 - 1.5 - - 1 6.6220 17.5 10 4 1.5 - - 1 6.621 13.5 10 4 - 1.5 - 1 4.5422 13.5 10 3 - 1.5 - 1 4.5523 14.5 10 3 - 1.5 - 1 4.8324 14.5 10 2 - 1.5 - 1 4.8925 15.5 10 2 - 1.5 - 1 5.2226 15.5 10 1 - 1.5 - 1 5.327 16.5 10 1 - 1.5 - 1 5.728 16.5 10 0.5 - 1.5 - 1 5.729 17 10 0.5 - 1.5 - 1 5.9730 17 10 0.2 - 1.5 - 1 5.9331 17.3 10 0.2 - 1.5 - 1 6.0232 17.3 10 - - 1.5 - 1 6.0133 17.5 10 - - 1.5 - 1 6.0934 17.5 10 - - 1.5 - 1 6.1335 17 10 - 0.5 1.5 - 1 6.3536 17 10 - 0.5 1.5 - 1 6.3137 16.5 10 - 1 1.5 - 1 6.4938 16.5 10 - 1 1.5 - 1 6.4939 16 10 - 1.5 1.5 - 1 6.6440 16 10 - 1.5 1.5 - 1 6.5741 20 10 - - - - - 6.0542 18 10 - - - 2.5 - 6.1143 19.5 10 - - - - 0.5 6.1244 18.6 10 - - - - 1.4 6.145 18 10 - - - - 2 6.1446 17 10 - - - - 3 6.1647 16 10 - - - - 4 6.1448 14 10 - - - - 6 6.15pHV

Golshid Hadialhejazi TRITA-LWR Degree Project 12:22APPENDIX 1. ALKALINITY RESULTS FOR THEGUADALAJARA SOILsoil sample VHCl Vsample Alkalinity pHG2 1.226 5 0.005321 6.83G4 1.013 5 0.004396 6.84G6 0.935 5 0.004058 7.05G8 0.861 5 0.003737 7.15G10 0.723 5 0.003138 7.24G12 0.575 5 0.002496 7.4G14 0.424 5 0.00184 7.62G16 0.277 5 0.001202 8.1G18 0.226 5 0.000981 9.06G20 0.371 5 0.00161 10.01G24 1.063 5 0.004613 6.77G26 0.909 5 0.003945 6.8G28 0.824 5 0.003576 7.11G30 0.668 5 0.002899 7.2G32 0.608 5 0.002639 7.39G34 0.434 5 0.001884 7.62G36 0.294 5 0.001276 8.06G38 0.235 5 0.00102 8.81G40 0.394 5 0.00171 9.92VI

Assessment of vanadium sorption by different soilsAPPENDIX 2. DATA USED FOR FREUNDLICH GRAPHSampleDissolved V(µg/l)DissolvedV (µmol/l)Addition V(µmol/l)Sorbed V(addition V-dissolved V)(µmol/l)Sorbed V(mmol/kgsoil)Log VsorbedLogdissolvedVZwijnaardeZ41 53.841 1.057 0 -1.057 -0.0159 -4.467 -5.976Z42 376.861 7.398 12.3 4.902 0.0735 -3.908 -5.131Z43 727.853 14.288 25 10.712 0.1607 -3.676 -4.845Z44 2175.249 42.702 70 27.298 0.4095 -3.338 -4.370Z45 3167.001 62.171 100 37.829 0.5674 -3.209 -4.206Z46 5061.101 99.354 150 50.646 0.7597 -3.092 -4.003Z47 6978.978 137.004 200 62.996 0.9449 -3.002 -3.863Z48 10918.097 214.332 300 85.668 1.2850 -2.875 -3.669Kungsängen D3KD3 41 Lower than the detection limitKD3 42 8.189 0.166 12.3 12.134 0.182 -3.740 -6.780KD3 43 17.091 0.347 25 24.653 0.370 -3.432 -6.460KD3 44 88.038 1.786 70 68.214 1.023 -2.990 -5.748KD3 45 158.762 3.221 100 96.779 1.452 -2.838 -5.492KD3 46 321.626 6.524 150 143.476 2.152 -2.667 -5.185KD3 47 551.520 11.188 200 188.812 2.832 -2.548 -4.951KD3 48 1045.500 21.208 300 278.792 4.182 -2.379 -4.673TerMunckT41 12.813 0.252 0 -0.252 -0.004 -4.466 -6.599T42 142.726 2.802 12.3 9.498 0.142 -3.744 -5.553T43 332.184 6.521 25 18.479 0.277 -3.501 -5.186T44 1228.850 24.123 70 45.877 0.688 -3.139 -4.618T45 2273.406 44.629 100 55.371 0.831 -3.061 -4.350T46 3195.904 62.739 150 87.261 1.309 -2.871 -4.202T47 3660.098 71.851 200 128.149 1.922 -2.708 -4.144T48 7869.278 154.481 300 145.519 2.183 -2.653 -3.811GuadalajaraG41 3.093 0.061 0 -0.061 -0.001 -4.955 -7.217G42 173.141 3.399 12.3 8.901 0.134 -3.837 -5.469G43 355.364 6.976 25 18.024 0.270 -3.549 -5.156G44 2965.212 58.210 70 11.790 0.177 -3.724G45 2210.248 43.389 100 56.611 0.849 -3.065 -4.363G46 3661.400 71.877 150 78.123 1.172 -2.927 -4.143G47 5152.593 101.150 200 98.850 1.483 -2.825 -3.995G48 8264.610 162.242 300 137.758 2.066 -2.682 -3.790Kungsängen A3KA3 41 Lower than the detection limitKA3 42 4.202 0.082 12.3 12.218 0.183 -3.737 -7.084KA3 43 9.765 0.192 25 24.808 0.372 -3.429 -6.717KA3 44 55.601 1.092 70 68.908 1.034 -2.986 -5.962KA3 45 114.391 2.246 100 97.754 1.466 -2.834 -5.649KA3 46 220.127 4.321 150 145.679 2.185 -2.661 -5.364KA3 47 371.861 7.300 200 192.700 2.891 -2.539 -5.137KA3 48 789.257 15.494 300 284.506 4.268 -2.370 -4.810VII