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沉淀法净化湿法磷酸反应机理的研究 总被引:5,自引:0,他引:5
探讨用湿法磷酸制饲料级磷酸氢钙时,采用沉淀法净化湿法磷酸的反应机理。着重介绍镁对产品质量的影响,脱镁过程的控制和脱镁反应动力学;氟在湿法磷酸中的赋存状态,脱氟反应过程和脱氟反应机理。 相似文献
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以四川金河磷矿制得的二水湿法磷酸为对象 ,采用化学沉淀法 ,研究沉淀剂种类、用量 ,加入方式 ,反应温度 ,反应时间 ,液相混合状况以及沉淀剂配制方法对脱除磷酸中氟的影响。将实验数据回归整理得到 :(1)沉淀剂用量与磷酸中剩余氟含量的关系式 ;(2 )磷酸的脱氟温度与磷酸中剩余氟含量的关系式。当磷酸中先加入 Na2 S·9H2 O,后加入 Na2 CO3(分别为脱氟所需理论用量的 10 0 %和 2 0 0 % ) ,在 2 5~ 30℃ ,反应 2 5~ 30 m in,则磷酸中剩余氟、砷和铅等的含量将降至很低 相似文献
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介绍了一种H2S循环脱湿法磷酸重金属的新工艺,通过对比分析了H2S循环脱湿法磷酸重金属新工艺与传统Na2S溶液脱重金属工艺的脱除效率、工艺安全性、循环经济性以及技术经济性,结论如下:H2S循环脱湿法磷酸重金属新工艺可以实现脱As后折85%H3PO4中As指标降至0.5mg/kg;本工艺拥有较高的工艺安全性、循环经济性、技术经济性,可使原料Na2S和NaOH的消耗量优化倍数达到了117、5.8倍,S元素的总利用率为94.5%,H2S循环脱重金属新工艺的尾气量由传统工艺的10 400 m3/kg(以As计)减至4 800 m3/kg(以As计)。 相似文献
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The present paper relates to the treatment of crude wet-process phosphoric acid with ammonium nitrate and hydrofluoric acid to precipitate aluminum and magnesium impurities in the form of an easily separable phase: (NH4)xMgyAlz (F, OH)6.2 H2O. To check the effect of some concentration factors on this reaction, an orthogonal central composite design is realized with three variables: %Al3+, %NH4+ and %F?. It is concluded that the amount of aluminum in acid is the limiting factor of magnesium precipitation. Thus complete removal of magnesium, which is a major impurity in wet-process phosphoric acid, can be obtained by adding to the crude acid extra soluble aluminum salt simultaneously with hydrofluoric acid and ammonium nitrate. 相似文献
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Roy A. Hutchins 《Nutrient Cycling in Agroecosystems》1993,36(3):193-201
Phosphoric acid of a quality high enough for most industrial and food grade markets and for the production of industrial and food grade phosphate derivatives in the United States has historically been produced by burning elemental phosphorus. However, in 1990, high quality phosphoric acid began to be commercially produced in the United States by purifying wet-process phosphoric acid via solvent extraction. The production facility, owned by Purified Acid Partners, is operated by Texasgulf Inc. with the product being marketed by Albright & Wilson Company (a partnership between Texasgulf Inc. and Albright & Wilson Americas, Inc.). In early 1991, Rhone-Poulenc began commercial production using different solvent extraction technology. This paper compares the production and quality of thermal and purified phosphoric acid, discusses the introduction of purified acid into the marketplace, and shows that it has been accepted for all but a few low volume applications requiring unique properties. 相似文献