Patent ID: 6864202

Claim:
A process for preparing a sodium silicate alkali solution depleted of sodium salt and enriched in silica from a mother liquor obtained after isolation of molecular sieves and suitably recycled further for preparing fresh sodium alumino silicate molecular sieves or as a binder for preparing Fluid Catalytic Cracking (FCC) catalyst, said process comprising steps of: a. recovering the mother liquor left after isolation of molecular sieves in a crystallizer; b. optionally adding to said mother liquor of step (a), a mineral acid in the range of 1-75% moles equivalent of Na 2 O moles present in the mother liquor with stirring; c. effecting crystallization of sodium salt by cooling the mother liquor of step (b) to a temperature ranging from 5 to 25° C. for a period ranging from 30 minutes to 48 hours, and d. filtering the crystalline sodium salt to yield the sodium silicate alkali solution depleted of sodium salt and enriched in silica.