硅质固体废物蒸压反应活性的红外光谱研究

通过红外光谱法研究了粉煤灰、陶瓷抛光废渣和煤粉炉渣等硅质固体废物-石灰体系的蒸压反应特性。6种硅质固体废物的红外光谱强吸收区Si—O伸缩振动频率分别为1103、1098、1094、1091、1078、1033 cm-1,硅质固体废物-石灰体系在160℃和1.2 MPa饱和蒸汽压下蒸压养护。结果表明,Si—O伸缩振动频率越低,其蒸压样品的结合水量越大,Ca(OH)2参与反应的比例越高,蒸压反应活性越高。单独硅质固体废物经蒸压处理,其傅立叶变换红外光谱(FTIR)显示,强吸收区的Si—O吸收谱带向低频率方向移动,表明其硅氧四面体聚合程度下降,反应活性增加。

Infrared Spectroscopic Studies of Autoclaved Reaction Activity of Silicious Solid Waste

The autoclaved reaction activities of six silicious solid waste-Ca(OH)_2 systems were studied by Fourier transform infrared(FTIR) spectroscopy. Three indices,viz. combined water amount of the hydration product,percentage of consumed Ca(OH)_2 and compressive strength of the product,were used to indicate the autoclaved reaction activity of silicious solid waste. Six silicious solid waste-Ca(OH)_2 systems were autoclaved at 160 ℃ and 1.2 MPa saturated vapor pressure,and their FTIR spectra were measured. The results showed that the Si-O stretching vibration wavenumbers of the IR absorption bands for 4 fly ashs,1 ceramic polishing waste and 1 cinder were 1 103,1 098,1 094,1091,1 078,1 033 cm~(-1),respectively. It was found that while the Si-O stretching vibration wavenumbers descreased from 1 103 to 1 033 cm~(-1),the combined water amount increased from 5.48% to 7.95%,the percentage of consumed Ca(OH)_2 increased from 72% to 94%,and the compressive strength of product increased from 13.9 to 25.8 MPa. Evidently,the Si-O stretching vibration wavenumber of silicious solid waste has a significant correlation with the autoclaved reaction activity,the lower wavenumber,the higher the reaction activity.