盐渍土活性的碱化学激发效果研究

Study on Effect of Alkali Chemical Activating Reactivity for Saline Soil

采用紫外可见分光光度计、XRD、IR等分析手段,研究了不同温度、时间条件下,5mol/L、10mol/L、15mol/L氢氧化钠化学激发盐渍土中活性组分SiO2和Al2O3的溶出及土体物相结构的变化规律;以氢氧化钠-水玻璃复合碱溶液激发制备盐渍土土质胶凝材料的强度为指标,探讨了盐渍土碱化学激发的效果。结果表明：活性组分的溶出程度随温度,时间及氢氧化钠浓度的变化而存在差异,土体的物相结构变化与SiO2和Al2O3的溶出存在对应关系,盐渍土中活性SiO2和Al2O3溶出的理想条件：氢氧化钠浓度10mol/L、温度60℃、时间24 h,经复合碱溶液激发后,盐渍土土质胶凝材料的强度提升2~3倍。

UV-Vis spectrophotometer,X-ray diffraction and Fourier transform infrared spectrometry were applied to investigate the affecting factors such as temperature,reaction time and NaOH concentrations on leaching rule of active ingredients（SiO2 and Al2O3）and the mineral composition variation of saline soil.Alkali-activated saline soil-based cementitious materials were prepared,and the effect of saline soil＇s alkali chemical activation was investigated.The results showed the dissolution extent of active ingredients varies with temperature,dealing time and NaOH concentrations changing.The variety of mineral composition corresponds to the dissolution of SiO2 and Al2O3.The ideal processing conditions of active ingredients leaching test are： 10 mol/L NaOH,60 ℃ and 24 h.The strength of saline soil-based cementitious materials will enhance 2-3 times after alkali-activated.