The insoluble residue was collected by filtration, washed with distilled water until the pH of filtrate was neutral, and then dried at 60 C in a hotair oven. The pH of supernatant fluid was adjusted to 5.5 with 10 % HCl and then concentrated.
The insoluble residue wascollected by filtration, washed with distilled water until thepH of filtrate was neutral, and then dried at 60 C in a hotairoven. The pH of supernatant fluid was adjusted to 5.5with 10 % HCl and then concentrated.