dc.description.abstract | Chitosan is one type of biopolymer that can react to various kiind of metalic ions found in waste solution and from chitosan - metal complex. The utilization of chitosan isolated from white shirup and crab by column and centrifugation method has been tested for the processing of waste solution from letaher industry. Result of the experiment showed that the use of solid crab's chitosan at 3 g per 450 ml waste solution by centrifugation method at 200 rpm for 60 minute gave the best result compared to other methods tested. Chitosan, beside reducing chrom concentration, was also able to reduce other pollution parame.t e' r such as COD, BOD, Color, cloudness, suspensable solid, and 'soluble solid., From the processing, .the concentration of chrom was reduced by 77.23%, COD 63.60%, BOD 84.80%, color 58.409, cloudiness 90.59%, suspensable solid 85.29%, and soluble solid was reduced by 12.39% | id |