| 摘要 |
A process and equipment which make it possible to recover high-purity phosphoric acid useful as a recycled matter in the form of a portable high-concentration liquid from phosphoric acid-containing water at high efficiency by simple constitution and operation. The process comprises subjecting phosphoric acid-containing water to both cation exchange and anion exchange, subjecting the resulting water to reverse osmosis under the condition of pH of 3 or below, preferably under the conditions of pH of 3 or below and a phosphoric acid concentration of 1 to 15wt%, to transmit acids (except phosphoric acid) and water to a permeating fluid chamber side with phosphoric acid concentrated on a concentrated fluid chamber side, desalting the permeating fluid with an ion exchanger to recover pure water, and evaporating the concentrated fluid with an evaporator to remove volatile components and water and recover a concentrated phosphoric acid solution. |
