微波辐射强化磷石膏水热合成α型半水石膏及作用机制  

Microwave Radiation Enhanced Hydrothermal Synthesis of α-hemihydrateGypsum from Phosphogypsum and Its Mechanism of Action

作　　者：梁青霞 陈禹彤 郑捷睿 杜伟凡 苏禹丹 周冰洁 李显波[1,2,3] LIANG Qingxia;CHEN Yutong;ZHENG Jierui;DU Weifan;SU Yudan;ZHOU Bingjie;LI Xianbo(Mining College,Guizhou University,Guiyang 550025,China;National&Local Joint Laboratory of Engineering for Effective Utilization of Regional Mineral Resources from Karst Areas,Guiyang 550025,China;Guizhou Key Lab of Comprehensive Utilization of Non-metallic Mineral Resources,Guiyang 550025,China)

机构地区：[1]贵州大学矿业学院,贵州贵阳550025 [2]喀斯特地区优势矿产资源高效利用国家地方联合工程实验室,贵州贵阳550025 [3]贵州省非金属矿产资源综合利用重点实验室,贵州贵阳550025

出　　处：《绿色矿冶》2025年第1期1-8,共8页Sustainable Mining and Metallurgy

基　　金：大学生“SRT计划”项目(贵大SRT(2022)325号);贵州省科技计划项目(黔科合基础-ZK[2022]一般070);国家自然科学基金(52204266)。

摘　　要：采用传统的电加热水热法制备α型半水石膏的时间较长,且添加转晶剂会进一步延长反应时间,降低生产效率。本文提出采用微波辐射加热快速合成α型半水石膏,并阐明微波辐射强化水热合成的作用机制。结果表明,当CaCl_(2)浓度为2.70 mol/L时,采用微波加热能在60 min内将磷石膏转化为α型半水石膏,而采用电加热需要180 min。在CaCl_(2)浓度为2.47 mol/L的条件下,采用失水苹果酸能有效地调控α型半水石膏的晶体形貌,获得短柱状α型半水石膏,但添加过多失水苹果酸会抑制磷石膏向α型半水石膏的转化,延长反应时间。与其他加热方法相比,微波辐射加热在缩短反应时间方面具有明显优势,还可以在一定程度上降低反应介质的浓度。原因是CaCl_(2)溶液和磷石膏均具有较大的介电常数,对微波表现出良好的吸收性能。此外,CaCl_(2)浓度越大,溶液的介电常数、介电损耗和电导率越大,吸波性能越好,可以快速加热反应料浆,促进磷石膏向α型半水石膏的转化。因此,微波辐射是一种高效、节能合成α型半水石膏的加热方式。Using traditional electric heating for preparation ofα-hemihydrate gypsum(α-HH)from phosphogypsum(PG)takes a long time,and the addition of modifier will further prolong the reaction time and reduce the production efficiency.This study proposed the rapid synthesis ofα-HH by microwave radiation heating,and the mechanism of microwave radiation enhanced synthesis ofα-HH was clarified.The results show that when the concentration of CaCl_(2) is 2.70 mol/L,the microwave heating can convert PG intoα-HH within 60 min,while the electric heating requires 180 min.Maleic acid can effectively regulate the crystal morphology ofα-HH and obtain short columnarα-HH in 2.47 mol/L CaCl_(2) solution,but adding too much maleic acid will inhibit the conversion of PG intoα-HH and prolong the reaction time.Compared with other heating methods,microwave radiation heating has significant advantages in shortening reaction time,and can also reduce the concentration of the reaction medium to a certain extent.The reason is that both CaCl_(2) solution and PG have a high dielectric constant,exhibiting a good absorption performance for microwaves.In addition,the higher the CaCl_(2) concentration,the greater the dielectric constant,dielectric loss,and conductivity of the solution,and the better the microwave absorption property,which can quickly heat the reaction slurry to promote the conversion of PG intoα-HH.Therefore,microwave radiation is an efficient and energy-saving heating method for synthesizingα-HH.

关 键 词：微波辐射 磷石膏 快速合成 Α型半水石膏 强化机制 

分 类 号：TQ177.375[化学工程—硅酸盐工业]