Effects of seed crystal concentration, pH, and stirring rate on ammonium sulfate crystallization under the action of ammonium nitrate

Effect of Evaporation Temperature and Mg2+ Concentration on the Crystallization of Ammonium Sulfate

“…15, 328.15, 333.15, 338.15, and 343.15 K and then cooled and crystallized without stirring. [18,19] Experiment on the effect of Mg 2+ concentration: Several mixtures of 160 g of ammonium sulfate dissolved in 200 mL of deionized water were prepared. Based on the effect of the evaporation temperature on the experimental results, Mg 2+ at concentrations of 0.0, 0.7, 0.8, 0.9, 1.0, and 1.1 g L −1 was added at the optimal evaporation temperature for constant-temperature evaporation for 2 h at a stirring rate of 200 rpm.…”

Evaporating crystallization effect of ammonium sulfate at atmospheric pressure under the action of ultrasound

“…At present, the methods used to crystallize ammonium sulfate include the addition of seed crystals, vacuum crystallization, antisolvent crystallization, and atmospheric pressure crystallization. By adding large particles of ammonium sulfate, other metal salts, fly ash, and urea [7] , [8] , ammonium sulfate grows on these large particles, which plays a role in inhibiting the spontaneous formation of small grains [9] , [10] , [11] , [12] . Although the addition of seed crystals can produce ammonium sulfate products with uniform particles and large particle sizes, there are strict requirements on the addition time and amount and the process operation is cumbersome [13] .…”