Nucleation thermodynamics and nucleation kinetics of (NH4)2SO4 under the action of NH4Cl

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

“…The reason is that the dissolution of ammonium sulfate is an endothermic reaction, so with an increase in temperature, the thermal motion energy of ammonium sulfate molecules is increased, and the interaction between molecules is accelerated, resulting in an increase in the entropy of the solution system and the dissolution rate and solubility of ammonium sulfate increase. [17] At the same temperature, the solubility of ammonium sulfate containing Mg 2+ is less than that in pure water and decreases gradually with an increase in the Mg 2+ concentration. Furthermore, the use of magnesium sulfate to adjust the Mg 2+ concentration introduces SO 4 2− , which inhibits the hydrolysis of ammonium sulfate and decreases its solubility.…”

“…The temperature at which the number on the FU-VLP-2000-MLKH digital display screen decreased rapidly, which indicated crystal precipitation, was recorded as T 1 . The difference between the nucleation and supersaturation temperatures was defined as the metastable zone width, expressed as △T max = T 0 −T 1 , [17] as shown in Figure 1.…”

Optimization of Ammonium Sulfate Crystallization under the Action of Ammonium Chloride Using the Response Surface Method

“…Ammonium sulfate produced from the ammonia desulfurization of sintering flue gas in a Chinese steel plant was selected as the research object to conduct experiments on the influence of various factors (seed crystal concentration, pH value, and stirring rate) on the crystallization of ammonium sulfate under the action of 7.5% ammonium chloride. 18 The evaporative crystallization device is shown in Figure 2. Finally, the crystals were allowed to cool naturally at a predetermined stirring speed.…”