Alkali-activation reactivity of chemosynthetic Al_2O_3-2SiO_2 powders and their ^(27)Al and ^(29)Si magic-angle spinning nuclear magnetic resonance spectra  

作　　者：Guangjian Zheng Xuemin Cui Dong Huang Jinying Pang Guowei Mo Shujuan Yu Zhangfa Tong 

机构地区：[1]School of Chemistry and Chemical Engineering,Guangxi University [2]College of Chemistry and Life Science,Guangxi Teachers Education University

出　　处：《Particuology》2015年第5期151-156,共6页颗粒学报（英文版）

基　　金：supported by the Chinese Natural Science Fund (Grant Nos.51262002 and 50962002);Guangxi Experiment Center of Science and Technology(Grant No.LGZXKF201202);Guangxi Natural Science Fund(Grant No.2014GXNSFAA118323);Research Project of the Education Department of Guangxi Government (Grant No.201204LX238);Opening Fund of Doctor Station Construction of Guangxi Teachers Education University

摘　　要：Pure Al2O3-2SiO2 powders were prepared by sol-gel and coprecipitation methods, and their alkaliactivation reactivities were compared. The alkali-activation reactivity of the powder prepared by the so]-gel method was higher than that of the powder prepared by the coprecipitation method. The powders were investigated by 27Al and 29Si magic-angle spinning nuclear magnetic resonance spectroscopy （MAS NMR） to understand the relationship between their structure and alkali-activation reactivity. The 27Al MAS NMR data showed that the five-coordinate AI content of the powder prepared by the sol-gel method was higher than that of the powder prepared by coprecipitation. The higher content of five-coordinate Al corresponded to higher alkali-activation reactivity. The 29Si MAS NMR data showed that for the powder prepared by the sol-gel method, silicon was replaced by aluminum at secondary coordination sites of the central Si atoms during calcination. However, for the powder prepared by single-batch coprecipitation, the main change was from a low degree of polycondensation to a high degree of polycondensation.Pure Al2O3-2SiO2 powders were prepared by sol-gel and coprecipitation methods, and their alkaliactivation reactivities were compared. The alkali-activation reactivity of the powder prepared by the so]-gel method was higher than that of the powder prepared by the coprecipitation method. The powders were investigated by 27Al and 29Si magic-angle spinning nuclear magnetic resonance spectroscopy （MAS NMR） to understand the relationship between their structure and alkali-activation reactivity. The 27Al MAS NMR data showed that the five-coordinate AI content of the powder prepared by the sol-gel method was higher than that of the powder prepared by coprecipitation. The higher content of five-coordinate Al corresponded to higher alkali-activation reactivity. The 29Si MAS NMR data showed that for the powder prepared by the sol-gel method, silicon was replaced by aluminum at secondary coordination sites of the central Si atoms during calcination. However, for the powder prepared by single-batch coprecipitation, the main change was from a low degree of polycondensation to a high degree of polycondensation.

关 键 词：GEOPOLYMER Al2O3-2SIO2 powder Alkali-activation reactivity NMR CHEMOSYNTHESIS 

分 类 号：O611.4[理学—无机化学]