霓辉正长岩制取铝酸钠溶液预脱硅的实验研究  

Pre-desilication of Sodium Aluminate Solution from Aegirine-augite Syenite:An Experimental Study

作　　者：王霞[1] 马鸿文[1] 俞子俭[1] 王晓艳[1] 邹丹[1] 

机构地区：[1]中国地质大学矿物材料国家专业实验室,北京100083

出　　处：《现代地质》2011年第1期157-162,共6页Geoscience

基　　金："十一五"国家科技支撑计划课题(2006BAD10B04)

摘　　要：霓辉正长岩提钾滤渣的主要物相为沸石Na6[AlSiO4]6.4H2O,富含氧化铝和氧化硅。采用高压水化学法对其进行碱热浸取可得到高苛性比的铝酸钠溶液,通过添加不同类型的脱硅剂对其进行一步脱硅法对比实验研究。正交实验结果表明,在脱硅的过程中,影响因素的顺序为:脱硅剂类型>脱硅时间>脱硅温度。通过进一步单因素实验,确定优化脱硅条件为:采用水合铝酸钙为脱硅剂,在160℃下反应3.5 h,即可制得硅量指数大于1 800的铝酸钠精制液。经X射线衍射分析,脱硅产物的主要物相为水化石榴石;扫描电镜及能谱分析结果显示,生成物水化石榴石的晶型较好,在晶粒细小处S iO2杂质容易附着,从而达到更好的脱硅效果。The principal phase of potassium-distilled filter residue of aegirine-augite syenite is sodium aluminum silicate hydrate rich in Al2O3 and SiO2.The high caustic ratio sodium aluminate solution was obtained from filter residue treated by high pressure hydrochemical process.The desilication reaction was experimentally studied by adding different types of desilication agents.The orthogonal experimental results show that in the process of the desilication from sodium aluminate solution,the descending order of affecting factors is as follows：desilication agent type,desilication time,desilication temperature.The optimal conditions of desilication are that the desilication agent is tricalcium hydroaluminate,and desilication temperature is 160 ℃ and the desilication time is 3.5 h.The silicon index of the refined aluminate solutions was obtained to be above 1,800 by one-step desilication procedure.According to X-ray diffraction analysis,the major phase of derived products is hydrogarnet.The diffraction intensity of hydrogarnet increases sharply with the desilication time increasing.The results of scanning electron microscopy and EDS analysis show that hydrogarnets reveal high crystallinity and perfect fine-grains,and SiO2 impurities easily attached with the small crystals,so a better effect of silicon removal is achieved.

关 键 词：霓辉正长岩 预脱硅 脱硅剂 水化石榴石 

分 类 号：P578.968[天文地球—矿物学] TQ170.4[天文地球—地质学]