10℃下K+,Ca2+//Cl-,SO42-,36%NH3-H2O体系相图的研究Study on the Phase Diagram of K+, Ca2+//Cl-, SO42-, 36%NH3-H2O System at 10℃
黄雪莉,吕秉玲
摘要(Abstract)：
为了探讨CaSO4·2H2O和KCl复分解生产K2SO4的工艺及最佳生产条件,特用恒温法研究了10℃K+,Ca2+//Cl?,SO42?,36%NH3-H2O体系相图。溶剂NH3-H2O中氨的浓度之所以选为36%,目的在于扩大K2SO4及CaSO4·K2SO4·H2O的结晶区;反应温度选为10℃,可降低氨的蒸气压。研究结果表明:在上述条件下,体系中存在K2SO4和CaSO4·K2SO4·H2O、CaSO4·K2SO4·H2O和CaSO4?2H2O的共饱线;存在K2SO4-CaSO4·K2SO4·H2O-KCl以及CaSO4·2H2O-CaSO4·K2SO4·H2O-KCl的三盐共饱点;K2SO4结晶区要比25℃,溶剂NH3-H2O中氨的浓度为25%的同体系相图大得多;K2SO4-CaSO4·K2SO4·H2O-KCl的三盐共饱点更偏向氯化钙一角,因此有利于CaSO4?2H2O和KCl复分解生产K2SO4;最佳工艺条件为2KCl(mol):CaSO4(mol):36%NH3-H2O(kg)=1:0.9023:0.5740,KCl的理论转化率可达90.22%;若想进一步提高KCl的理论转化率,必须加大氨的浓度。
关键词(KeyWords)： 石膏;氨;氯化钾;硫酸钾;相图
基金项目(Foundation):
作者(Author): 黄雪莉,吕秉玲
参考文献(References)：
- [1]SHU Lan(舒兰),FAN Cai-mei(樊彩梅),YU Hua-rui,et al.(余华瑞等).Study on the solubility data of K+,NH4+//Cl?,SO42?system in water and in ammonia at40℃(40℃K+,NH4+//Cl?,SO42?体系在水中及氨水中的溶解度数据测定)[J].J Chem Eng of Chinese Univ(高校化学工程学报),1999,13(1):62-65.
- [2]YANG Lin-jun(杨林军),QI Jia-hui(漆嘉惠),ZHANG Yun-xiang,et al.(张允湘等).Study on K2SO4crystallization in potassium sulfate production by two-step conversation of gypsum(石膏两步法制硫酸钾中K2SO4结晶工艺条件研究)[J].J Chem Eng of Chinese Univ(高校化学工程学报),2004,18(1):89-93.
- [3]СафрыгинЮС,ВукщаЮВ,ПаскинаАВ.Study on the manufacture of Syngenite by K+,Ca2+//SO42?,Cl?,NH3-H2O system at25℃(ИсследованиеУсловииКонверсионногоПолученияСингенитавСистеме,K+,Ca2+//SO42?,Cl?,NH3-H2Oпри25℃)[J].JAPP Chem.(ЖΠХ),1986,(2):245-250.
- [4]Fernandez Lozano J A,Wint A,The manufacture of potassium sulfate[J].Chem Eng,1979,349,(10):688-690.
- [5]MA Xin-hua(马欣华).Study on the technology of potassium salt separated from the brine(海盐卤水提取钾盐工艺技术的研究)[J].Sea-Lake Salt and Chemical Industry(海湖盐与化工),1995,24(4):1-7.
- [6]Perry R H,Chilton C H.Chimcal Engineer’s Handbook[M].7th ed.Newyork:MeGraw-Hill Book Company,2001.
- [7]CAO Ji-lin(曹吉林),BAI Peng(白鹏),WANG Shi-chang(王世昌).Study on phase equilibria of H3BO3-Na2SO4-NaCl-H2O system at25℃and100℃(25℃和100℃时H3BO3-Na2SO4-NaCl-H2O体系的相平衡)[J].J Chem Eng of Chinese Univ(高校化学工程学报),1999,13(1):1-4.
- [8]Jaroslav Nyvlt.Solid-liquid Phase Equilibria[M],Praha:Publishing House of the Czechoslovak,1977.
- [9]HUANG Xue-li(黄雪莉),LU Bing-ling(吕秉玲).Study on phase diagram and experimental progress of potassium sulfate made from calcium sulfate(硫酸钙制取硫酸钾相图及实验研究进展)[J].Inorganic Chemicals Industry(无机盐工业),2002,34(1):29-31.