化学催化法综合利用磷石膏的研究

Study on comprehensive utilization of phosphorus gypsum by chemical catalyst method

探讨一种利用催化剂处理磷石膏的方法。在催化剂作用下,将磷石膏转化成硫酸、氯化钙,并副产氨水、干冰等化工原料。按3∶1的水料质量比向磷石膏中加水,搅拌、静置、固液分离,反复洗3次。将水洗后的磷石膏与碳酸氢铵混合,碳酸氢铵过量5%,加入体积2倍于原料的水,常温下搅拌50 min。将上述物料分离,固体常温下与浓盐酸反应至无气体放出。硫酸铵溶液蒸干后与催化剂混合均匀,催化剂过量50%,500℃反应1.5 h,继续升温至800℃反应0.5 h,同时用浓硫酸吸收三氧化硫气体制取所需浓度的硫酸。该方法有助于解决磷石膏的占地及环境污染问题,实现资源有效利用。

A kind of processing method for phosphorus gypsum with catalyst was discussed.Under the action of catalyst,phosphorus gypsum was transformed into sulfuric acid and calcium chloride,as well as by-product ammonia and dry ice etc..Add water to phosphorus gypsum according to a 3∶1 mass ratio of water to solid material,Then stir,put it aside,separate solid and liquid and repeat those for 3 times.Mix phosphorus gypsum after washing with ammonium bicarbonate and ammonium bicarbonate excess of 5%.Then add water whose volume is 2 times as much as that of the raw materials,at room temperature,stir 50 min.Separate the above-mentioned material and solid reacts with concentrated hydrochloric acid until there is no gas released at room temperature.After ammonium sulfate solution was evaporated,mix it with catalyst,catalyst excess of 50%,at temperature of 500 ℃ for 1.5 h.Then continue to heat up to 800 ℃ for 0.5 h,and absorb sulfur trioxide with concentrated sulfuric acid to produce the sulfuric acid with required concentration at the same time.This method is conductive to solving the problems,such as floor space cost and environmental pollution of phosphorus gypsum,and the resources can be effective used.