FLOCCULANT FOR PHOSPHORIC ACID HAVING CHITOSAN AS EFFECTIVE COMPONENT AND METHOD FOR REMOVAL OF PHOSPHORIC ACID USING THE SAME

摘要

PROBLEM TO BE SOLVED: To reduce a remaining metal ion while a phosphoric acid removing rate is improved by a method wherein an inorganic flocculant and chitosan are combined with each other. ;SOLUTION: A flocculant for phosphoric acid is a flocculant containing chitosan with which preferably an inorganic flocculant composed of iron sulfate or aluminum sulfate as an effective component, or a flocculant for phosphoric acid is combined. The most important physical property of chitosan as polymer flocculant is molecular weight. Thoush it is generally known that as the polymer flocculant the higher molecular weight one can form the larger flock with the less additional rate, an appropriate molecular weight exists in the case of cationic polymer flocculant used for aggregation and hydrophylization of excess activated sludge or the like. Since the molecular weight is low in the case of chitosan, in those manufactured presently the higher molecular weight one may be the more effective one. Strictly the optimum chitosan is selected by confirming preliminarily with an aggregation test or a dehydration test. The chitosan is generally used under a solution state prepared with acid.;COPYRIGHT: (C)1998,JPO