The Effect of Acetic Acid and Hydrochloric Acid as a Solvent for Chitosan to Reduce Turbidity in Eutrophic Water

Abstract

In this research, the potential of chitosan as a coagulant to reduce the turbidity of eutrophic water was investigated. To examine the possible effect of the solvent of chitosan on its performance in reducing the turbidity of eutrophic water, different types of acid, i.e. acetic acid and hydrochloric acid, were used to dissolve chitosan, in which the concentration of each acid was also varied. The chitosan dissolved in acetic acid was labeled as Chit-AA while the one being dissolved in HCl was labeled as Chit-HCl. A standard jar test apparatus was used to determine the optimum dosage and coagulation pH for both Chit-AA dan Chit-HCl. Both Chit-AA and Chit-HCl gave optimum results at a dosage of 10 mg/L, where the turbidity reductions after coagulation with Chit-AA and Chit-HCl were 64.78% and 85.33%, respectively. The optimum coagulation pH for Chit-AA was pH 7 while Chit-HCl gave an optimum result at pH 8. The concentration of the acid being used to dissolve chitosan appeared to affect the decrease in turbidity, where a higher acid concentration lead to a higher decrease in turbidity.