磷石膏制备纳米CaCO_(3)的碳化工艺条件研究  

Study on carbonization process conditions for preparation of nano-CaCO_(3) from phosphogypsum

作　　者：涂新悦 杨保俊 王琦 王百年 张如 TU Xin-yue;YANG Bao-jun;WANG Qi;WANG Bai-nian;ZHANG Ru(School of Chemistry and Chemical Engineering,Hefei University of Technology,Hefei 230009,China)

机构地区：[1]合肥工业大学化学与化工学院,安徽合肥230009

出　　处：《现代化工》2023年第10期214-221,共8页Modern Chemical Industry

摘　　要：以工业固废磷石膏、CO_(2)为原料,采用“相转移-沉淀法”制备纳米CaCO_(3)并考察其碳化工艺条件。结果表明,适宜的复合晶形控制剂及其配比为2.5%STPP+0.5%PDS;适宜的碳化沉淀反应工艺条件为:复合晶形控制剂添加质量分数为3%、碳化终点pH为12.40、碳化反应温度为15℃、陈化时间为0 min。该条件下所制备的纳米CaCO_(3)样品为纯相方解石型CaCO_(3),样品的平均粒径约30 nm,分散性好且粒度较为均匀。晶形控制剂在纳米CaCO_(3)形成的作用机制为PDS的模板诱导作用,以及Ca^(2+)与晶型控制剂水解产生的磷酸根间鳌合、电离所形成的P3O105-离子在CaCO_(3)晶核上的选择性吸附等的协同作用,有效抑制了CaCO_(3)晶粒的生长及其颗粒间团聚,促进了粒径小、粒度均匀、分散性好的纳米CaCO_(3)的形成。A"phase transfer-precipitation method"is employed to prepare nano-CaCO_(3) from phosphogypsum,an industrial solid waste,and CO_(2),and study the carbonization process conditions.It is found through screening experiments that the formula of suitable compound crystal shape control agent is 2.5%STPP+0.5%PDS.Through the single factor experiment,the optimum carbonation precipitation reaction conditions are determined as follows:the adding amount of compound crystal shape control agent is 3%,the final pH value of carbonation is 12.40,the carbonization reaction temperature is 15℃,and the aging time is 0 mi.The nano CaCO_(3) sample prepared under these conditions is pure phase calcite CaCO_(3),and has an average particle size of about 30 nm,showing a good dispersion and uniform particle size.It is concluded that the mechanism of the crystal control agent in the formation of nano-CaCO_(3) may be the synergistic effects formed by the template induction of PDS,the chelation between Ca^(2+)and phosphate radical generated in the hydrolysis of crystal control agent,and the selective adsorption of P3O5-10 ions formed by ionization on the nucleus of CaCO_(3),which can effectively inhibit the growth of CaCO_(3) grains and the agglomeration between grains,and promote the formation of nano-CaCO_(3) with small particle size,uniform particle size and good dispersion.

关 键 词：磷石膏 纳米CaCO_(3) 晶形控制剂 相转移-沉淀法 

分 类 号：TQ132.32[化学工程—无机化工]