沉淀—水热法制备超细Al(OH)_3γ—AlOOH和Al_2O_3  

PREPARATING ULTRAFINE POWDER OF Al(OH)_3,γ-AIOOH AND Al_2O_3 BY PRECIPITATIONH YDROTHE RMAL-CALCINING

作　　者：施惠娟[1] 毛铭华[1] 梁唤珍[1] 康萤[1] 陶昌源[1] 

机构地区：[1]中国科学院化工冶金研究所

出　　处：《有色金属》1990年第4期53-57,共5页Nonferrous Metals

摘　　要：本文介绍一种超细铝的氧化物及水合物的制备方法,沉淀—水热—烧结法。用碳酸钠作沉淀剂,快速沉淀硫酸铝,可获得粒径0.02～0.08μm的无定型Al(OH)_3。详细讨论了各种因素(溶液pH、温度、Al^(3+)浓度、沉淀剂用量)对沉淀产物的影响。沉淀物Al(OH)_3的浆料在250～300℃下水热处理2小时,得到γ-AlOOH,其粒径和Al(OH)_3的粒径相当。实验发现,温度是影响水热过程的主要因素;在不同pH下水热脱水,脱水产物的形状不同,pH<4时为针状γ-AlOOH,pH≥7时为片状γ-AlOOH;添加某些添加剂亦可获得球形γ-AlOOH。对Al(OH)_3直接加热脱水和水热脱水进行了比较,发现在相同温度(250—300℃)和相同时间(2小时)条件下,水热脱水具有晶体结晶完全和γ-AlOOH相纯度较高的优点。文中对γ-AlOOH在温度>1000℃下烧结成Al_2O_3进行了研究。A method of preparating ultrafine powder of Al(OH)_3, γ-AlOOH and Al_2O_3 by precipitation-hydrothermal-calcining was described in this paper. Aluminum hydroxide was obtained by precipitating aluminum sulfate with Na_2CO_3, and the effects of several conditions, including pH, temperature, concentration of Al^(3+), precipitating agent amount were studied. The size distribution of Al(OH)_3 was in range of 0.02 —0.08μm.Suspension solution of Al(OH)_3 was dehydrated by hydrothermal in autoclave at 250℃ for 2 ho...

关 键 词：OH 热脱水 AI 粒径 AL2O3 水热法 实验条件 水热处理 超细 

分 类 号：TD862[矿业工程—金属矿开采] TF80[矿业工程—矿山开采]