膜分散微反应器沉淀法制备高孔容SiO_2材料  

Preparation of silica material with high pore volume by precipitation in membrane dispersion reactor

作　　者：李亚丹[1,2] 王玉军[1] 张卫东[2] 骆广生[1] 

机构地区：[1]清华大学化学工程系化学工程联合国家重点实验室,北京100084 [2]北京化工大学化学工程学院,北京100029

出　　处：《化工学报》2013年第6期2276-2284,共9页CIESC Journal

基　　金：国家重点基础研究发展计划项目(2013CB733600);国家自然科学基金项目(20976096;21036002);中国石油科技创新基金研究项目(2011D-5006-0407);清华大学基础科研项目(20121087993)~~

摘　　要：高孔容二氧化硅具有良好的光学性能，是高档涂料消光剂的首选，其消光效率随着孔体积的增大而提高。这是因为较高孔隙率的颗粒较轻，单位质量颗粒数较多，而颗粒对光的折射是产生消光所需的微粗糙度的主要原因。The key issue of preparing high pore volume material is strengthening the microscopic supersaturation of precipitation reaction and reducing the particle size. Ultrafine SiO2 was prepared with the fast precipitation method in a membrane dispersion micro-reactor by using sodium silicate and sulfuric acid as raw material. The effects of two-phase flow rates, final pH, salt concentration, aging time, and drying temperature on the specific surface and pore volume were investigated. The results showed that silica powder primary particle size prepared with the membrane dispersion micro-reactor was 10.2 nm, while primary particle size prepared with the stirring method was 20.8 nm, specific surface could be up to 380 m2 . g -1 and pore volume was 2.6 ml . g -1 when final pH value was 9.55. Flatting performance test of SiO2 showed that the SiO2 prepared with the membrane dispersion micro-reactor had excellent flatting performance, and extinction index of SiO2 was up to -10.2.

关 键 词：消光剂 二氧化硅 高孔容 高比表面积 快速沉淀 膜分散微反应器 

分 类 号：TB321[一般工业技术—材料科学与工程]