Joint International Conference on Long-term Experiments ...

RESEARCH REGARDING MAIN CHEMICAL REACTIONS IN
PREDEFECATION OF DIFFUSION JUICE
Gheorghe Sarca
University of Oradea, Faculty for Environmental Protection
ABSTRACT
The quality of sugar is the decisive factor in ensuring the sugar commercializing
through the conservation of old markets and expansion towards new markets. The sugar
quality is also the key element which determines the price maintenance in according
with the expenditures performed or even the diminution of the price as a consequence of
the quality lessening.
INTRODUCTION
The main chemical reactions occurred in the predefecation of diffusion juice are the
following:
• Neutralisation of free acids, especially the neutralisation of the organic acids of
sugar beet and of the mineral acids contained in the extraction water:
2 R COOH + Ca(OH)2→ (R COO) 2Ca + H2O
• Ions exchange between magnesium and calcium which can be mainly described by
the intermediate of a chemical reaction such as:
2 R COOMe + Ca(OH)2+ Ca(OH)2→ (R COO) 2Ca+2MeOH
At pre-defecated juice defecation the following chemical reactions take place:
R CONH2 + H2O → R COONH4
H2O + R CONH2 → R COOH + NH2
H2O + CO2 → H2CO3
H2O + CaO → Ca(OH)2
Reduction substances + Ca(OH)2 → Colouring Substances + Organic Acids
During defecated juice carbonizing the following reactions take place:
CO2 + H2O → H2CO3
CO2 + OH → HCO?
H2Co3 + Ca(OH)2 → CaCO3 + H2O
An important role in providing the adequate conditions for the development of these
reactions is taken by the calcium oxide solubility in water and in the sugar-in-water
impure solutions. As higher level of calcium oxide solubility is as better the purification
effect would be. In the chart 1 the solubility of the oxide calcium solved in water and in
sucrose solutions is presented.
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