氧化钙和氢氧化钠混合分解锆英砂的工艺及机理  

Decomposition Process and Mechanism for Zircon with Mixed CaO and NaOH

作　　者：张建东[1] 陈洋[1] 张顺利[1] 王力军[1] 

机构地区：[1]北京有色金属研究总院,北京100088

出　　处：《钛工业进展》2013年第2期38-42,共5页Titanium Industry Progress

基　　金：国家科技支撑计划(2012BAB10B10)

摘　　要：以氧化钙替代部分氢氧化钠进行混合碱分解锆英砂实验,研究了反应温度、原料配比和反应时间对锆英砂分解率的影响,探讨了氧化钙与氢氧化钠混合分解锆英砂的机理。结果表明:随着反应温度的升高和反应时间的延长,锆英砂分解率逐渐增加;在反应温度800℃和反应时间1 h的条件下,氧化钙与锆英砂物质的量比在0.25～0.75时,锆英砂分解率高于97%,物质的量比超过0.75时,分解率逐渐降低。进一步的机理分析表明:氧化钙与Na4SiO4反应生成Na2CaSiO4和Na2O,Na2O扩散到锆英砂表面继续进行分解反应。The decomposition process for zircon using mixed base of NaOH partly replaced by CaO has been re-searched and the mechanism of decomposition process for zircon using mixed alkali was also studied. The influence of varying experimental conditions on the process was studied including reaction temperature, material ratio and duration. The investigation shows that zircon decomposition rate gradually increases as reaction temperature rising and duration prolonging. The decomposition rate is over 97% with the condition that the CaO/zircon molar ratio of 0. 25 - 0. 75 at 800 ℃ for 1 h. Whereas the decomposition rate decreases when the molar ratio over 0.75. Further research found that Na20, which is generated by the reaction of CaO and Na4SiO4, spread to the surface of zircon to continue the decom-position process.

关 键 词：锆英砂 分解率 氧化钙 氢氧化钠 

分 类 号：TQ134.12[化学工程—无机化工]