摘要
以硼精矿为原料、Na2CO3为钠化剂,在TG-DTA热分析基础上,研究了硼精矿钠化焙烧-水浸制取硼砂过程中Na2CO3用量、焙烧温度、焙烧时间、成型压力对B2O3浸出率的影响,采用X射线衍射和扫描电镜对硼精矿钠化焙烧产物和硼砂制品的相组成和显微形貌进行了表征分析。结果表明:在5倍Na2CO3理论用量、样品成型压力5 MPa、温度850℃、保温3 h最优条件下,硼精矿中主要含硼矿物硼镁石[MgBO2(OH)]转变为可溶性硼酸钠盐Na3BO3和Na2B4O7,实现了硼矿物活化和碱解过程同步完成。焙烧产物经常压水浸,B2O3浸出率达91.05%。水浸滤液经除杂、蒸发、浓缩后获得了结晶良好的硼砂制品。
Based on TG-DTA analysis, a sodium-roasting and water-leaching process were employed for the preparation of borax from boron concentrate, using Na2CO3 as sodium treatment reagent. The effects of Na2CO3 content, roasting temperature and holding time on leaching rate of B2O3 were investigated. Phase compositions and morphologies of roasted products and borax were analyzed by XRD and SEM. The results indicate that the optimal processing parameters are fivefold theoretical amount of Na2CO3, molding pressure of 5 MPa, roasting temperature of 850℃and holding time of 3 h. Under these conditions, activation and alkaline hydrolysis of boron mineral are completed synchronously, which make transformation of MgBO2（OH） into soluble Na3BO3 and Na2B4O7. The leaching rate of B2O3 in roasted products reaches 91.05%. Well-crystallized borax is obtained from leached filtrate after treatments of removing impurity, evaporation and concentration.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2014年第2期737-743,共7页
CIESC Journal
基金
国家自然科学基金项目(51374052)
教育部新世纪优秀人才支持计划项目(NCET-11-0074)
中华环保基金会'123'工程项目(CEPF2011-123-2-6)~~
关键词
硼精矿
钠化焙烧
浸取
硼砂
boron concentrate
sodium roasting
leaching
borax
