Patent ID: 8753519

Claim:
A process for removing silicon compounds from aqueous NaCl brine, comprising: a) adjusting a brine with weak NaCl concentration by adding hydrochloric acid to obtain an acidified brine with a pH value of less than 3; b) adding iron(III) chloride or other trivalent iron ions to the acidified brine obtained from step a) to obtain a mixture; c) continuously feeding the mixture thus obtained from step b) to a stirred dissolution vessel which contains undissolved salt in addition to brine; d) charging the stirred dissolution vessel batchwise and intermittently with fresh salt to obtain brine with strong NaCl concentration; e) feeding the brine with strong NaCl concentration obtained from step d) to a stirred buffer vessel; f) maintaining the pH value in the stirred buffer vessel at a level ranging from 5 to 8; g) continuously withdrawing and filtering a flow of brine with strong NaCl concentration from the stirred buffer vessel; and h) discharging a filter cake containing the added iron and the silicon compounds.