Novel process for facile preparation of mesoporous silica-based materials with controllable pore structure from coal fly ash Author links open overlay panel  

作　　者：Jian-ming Gao Zhen Li Shujia Ma Yuanyuan Zhang Fangqin Cheng 

机构地区：[1]Institute of Resources and Environment Engineering,State Environmental Protection Key Laboratory of Efficient Utilization Technology of Coal Waste Resources,Shanxi Collaborative Innovation Center of High Value-added Utilization of Coal-related Wastes,Shanxi University,Taiyuan 030006,China

出　　处：《Particuology》2024年第8期128-137,共10页颗粒学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(grant Nos.U21A20321 and 21908138);Shanxi Province Central Government Guided Local Science and Technology Development Fund Project(grant No.YDZJSX2022A004);Shanxi Province Scientific and Technological Innovation Project of Colleges and Universities(grant No.2020L0009).

摘　　要：Extraction of silica from fly ash to produce mesoporous silica materials is one of the most important utilization approaches.Mesoporous silica could not be synthesized on a large-scale by conventional sol-gel method.In this paper,facile preparation of mesoporous silica with controllable pore structure from fly ash by the template-free process via two steps of mineral phase transformation and selective acid etching was proposed.The influence of crystalline structure and acid etching degree on structure of as-synthesized mesoporous silica materials was revealed,as well as mechanism of crystalline structure transformation and pore structure formation.The results show that mullite and quartz could be transformed into acid-soluble kaliophilite when fly ash reacted with K_(2)CO_(3)at temperature of 800-1100℃.The hexagonal kaliophilite would be transformed into orthorhombic KAlSiO_(4)-O1 phase when the temperature is controlled at 1100℃.Mesoporous silica with specific surface area of 475.93 m^(2)/g and 642.57 m^(2)/g could be synthesized from activated fly ash with kaliophilite and KAlSiO_(4)-O1 phase crystalline structure.By controlling the degree of acid etching,mesoporous silica materials with different pore structures can be obtained.This paper provides a cost-effective and large-scale process for the preparation of mesoporous silica materials with controllable pore structure from solid waste fly ash.

关 键 词：Fly ash Mesoporous silica Crystal transformation Acid etching Controllable pore structure 

分 类 号：TB33[一般工业技术—材料科学与工程]