Two processes for purifn. of (NH4)(2)SO4 were computer-simulated to compare their efficiency. One of the processes was also verified exptl. Both oil and aq. solns. of caprolactame from rearrangement of cyclohexanone oxime were extd. with PhMe to recover caprolactame. Pure (NH4)(2)SO4 was sepd. from its aq. soln. by crystn. The removal degree of impurities was 86% by mass. The exptl. data agreed well with the simulation results. The optimum process flow sheet was proposed.