Characteristic and structure of calcium sulfate dihydrate crystallites in crystallization process during reaction

被引：0
|
作者：
Dou Y. [1 ]
Liu T. [1 ]
Shen H. [2 ]
Zheng Z. [2 ]
Liu R. [2 ]
Cui P. [1 ]
机构：
[1] School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei, 230009, Anhui
[2] Anhui Liuguo Chemical Co., Ltd., Tongling, 244000, Anhui
来源：
Huagong Xuebao/CIESC Journal | 2016年 / 67卷 / 06期
关键词：
Calcium sulfate dihydrate; Crystallization; Preparation; Process; Reaction;
D O I：
10.11949/j.issn.0438-1157.20151942
中图分类号：
学科分类号：
摘要：
In CaHPO4·2H2O-H2SO4-H3PO4-H2O system, an orthogonal experiment with five factors and four levels, including crystallization temperature, SO42- concentration and P2O5 concentration in liquid phase (solution), stirring rate and crystallization time was designed. Based on the measurement of average particle size, the optimized process parameters for the maximum mean particle size are, 80℃ of crystallization temperature, 50 g·L-1 of SO42- concentration, 260 g·L-1 of P2O5 concentration, 50 r·min-1 of stirring speed, and 2 h of crystallization time. Under the optimum conditions of the crystallization process, by means of analyses on the concentrations of SO42- and P2O5 in solution, and the techniques of XRD, SEM, EDS and laser particle size measurement, it showed that the reaction stage was the first 40 min with a decrease in mean particle size, and after 40 min, the procedure of crystallization follows the Ostwald grading rules, along with the evolution from CaSO4·0.5H2O to CaSO4·2H2O, but with almost identical particle size. © All Right Reserved.
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页码：2449 / 2455
页数：6
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