BIOSORPTION OF Pb2+, Cd2+, & Ni2+ FROM WATERS BY ...

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Biomass-Agarose Mixture Agarose immobilized biomass beads 1 = 1 q e K Kac ac m * 1 c e + Oil-H Oil-H2O 2O Figure 2.3. Apparatus used in the immobilization of algae into agarose by interphase technique 2.7. Sorption Isotherm Models The sorption isotherms are the mathematical models which provides an explanation about the behaviour of adsorbate species between solid and liquid phases. Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm models were studied for the investigation of biosorption of Pb 2+ , Cd 2+ , and Ni 2+ by Dunaliella salina, Oocystis sp., Porphyridium cruentum, and Scenedesmus protuberans. Langmuir isotherm model is based on the complete monolayer coverage on the adsorbent surface. Langmuir isotherm model is expressed by the following equation 2.1 (Mumin, et al. 2007): q e = q m K a c e 1 + K c a e The above equation can be rearranged to the following linear form: 1 c m (2.1) (2.2) 29
where ce is the equilibirium concentration (mg/L), qe the amount of Pb 2+ , Cd 2+ , and Ni 2+ ions biosorbed (mg/g), cm is qe for a complete monolayer sorption capacity (mg/g), Ka is a sorption equilibrium constant (L/mg). The values of cm and Ka were determined from the intercept and the slope of 1/qe versus 1/ce; the linearized form of Langmuir equation 2.2. Freundlich isotherm model is based on the assumption of heterogeneous surfaces as well as multilayer sorption and also being the binding sites are not equivalent. It is expressed by the equation (Şeker, et al. 2008): q e = K f c e n The above equation can be rearranged to the following linear form: log q e = log K f + n log c e q e = c m exp(-kɛ 2 ) ɛ = RT Ln (1 + 1/ce) The equation (5) can be rearranged to the following linear form: Ln q e = Ln c m - kɛ 2 (2.3) (2.4) where Kf and n are isotherm constants, respectively. The values of Kf and n are calculated from the intercept and the slope of logqe versus logce; the linear form of Freundlich equation 2.4. Another isotherm model applied in this study is Dubinin-Radushkevich isotherm model. The basic principles of this model is the Polany’s adsorption potential theory and Dubinin’s minipore filling theory. Dubinin-Radushkevich isotherm model can be given by the equation (Shahwan, et al. 2005): where (2.5) (2.6) (2.7) where cm and k are the constants of Dubinin-Radushkevich isotherm model,respectively, the maximum adsorption capacity (mol/g) and the adsorption 30
Page 1 and 2: BIOSORPTION OF AQUEOUS Pb 2+ , Cd 2
Page 3 and 4: ABSTRACT BIOSORPTION OF AQUEOUS Pb
Page 5 and 6: Anyone who has never made a mistake
Page 7 and 8: 2.3. Instrumentation and Apparatus.
Page 9 and 10: Figure 3.16. Effect of biosorbent a
Page 11 and 12: LIST OF TABLES Table Page Table 1.1
Page 13 and 14: · or the change of active conforma
Page 15 and 16: possible kidney disease is as a res
Page 17 and 18: 1.3.1. Heavy Metal Determination Te
Page 19 and 20: leads to develop an economical and
Page 21 and 22: cell metabolism. From the other poi
Page 23 and 24: 3. The metal removal is influenced
Page 25 and 26: 1.5. Algae Living or dead algal cel
Page 27 and 28: 1.5.1. Dunaliella salina Dunaliella
Page 29 and 30: Scenedesmus exists comonly in the p
Page 31 and 32: 1.6.1.2. Entrapment in Polymeric Ma
Page 33 and 34: 2.1. Preparation of Biosorbents CHA
Page 35 and 36: 24 Table 2.1. The properties of che
Page 37 and 38: temperature, and successive loading
Page 39: 2.6.2. Immobilization of Biosorbent
Page 43 and 44: CHAPTER 3 RESULTS AND DISCUSSION 3.
Page 45 and 46: Table 3.1. IR stretching frequencie
Page 47 and 48: Table 3.2. Elemental composition of
Page 49 and 50: Figure 3.6. TGA decomposition curve
Page 51 and 52: the underlying mechanism of sorptio
Page 53 and 54: Concentration (x10 -5 Concentration
Page 55 and 56: Sorption (%) 100.0 80.0 60.0 40.0 2
Page 57 and 58: such as 10.0, 20.0, 50.0, 100.0, an
Page 61 and 62: Desorption (%) Desorption (%) 100.0
Page 63 and 64: Table 3.6. Competitive biosorption
Page 67 and 68: 3.6.1. Immobilization of Oocystis s
Page 69 and 70: 3.7. Sorption Isotherm Results The
Page 71 and 72: 1/q e 1/q e 1/q e 0.12 0.10 0.08 0.
Page 73 and 74: 1/q e 1/q e 1/q e 0.12 0.10 0.08 0.
Page 75 and 76: logq e logq e logq e -7.00 -6.00 -5
Page 77 and 78: logq e logq e logq e -7.00 -6.00 -5
Page 79 and 80: lnq e lnq e lnq e 0.00 0.00E+00 -2.
Page 81 and 82: lnq e lnq e lnq e 0.00 0.00E+00 -2.
Page 83 and 84: qe (x10-3 qe (x10 mol/g) -3mol/g) q
Page 85 and 86: qe (x10-3 qe (x10 mol/L) -3mol/L) q
Page 87 and 88: CHAPTER 4 CONCLUSION It has been sh
Page 89 and 90: REFERENCES Agency for Toxic Substan
Page 91 and 92:
López A., N. Lázaro, A.M. Marqué
Page 93 and 94:
Volesky B. 2007. Biosorption and me
Page 95:
BBM KOH Solution Contents Concentra
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