煤矸石酸碱一步催化法制备SiO2气凝胶

以山西朔州煤矸石为单一硅源, 采用酸碱一步催化法制备超疏水二氧化硅气凝胶材料。通过单因素浸出试验, 考察了盐酸浓度和酸浸温度对氧化铝浸出的影响、氢氧化钠浓度和碱浸温度对二氧化硅浸出的影响、酸碱一步催化时盐酸浓度对气凝胶的影响。结果表明:当酸浸过程中盐酸浓度为3 mol/L、酸浸温度100 ℃、氢氧化钠浓度3 mol/L、碱浸温度80 ℃、酸碱一步催化过程中的盐酸浓度为2 mol/L时，氧化铝浸出率达81.26%、二氧化硅浸出率达86.53%，气凝胶样品的表观密度、比表面积和疏水角分别为0.04 g/cm3、610.68 m2/g和144.8°。该技术为煤矸石的综合利用提供了一种有效途径。 

Preparation of SiO2 Aerogel from Coal Gangue by One-step Acid-base Catalytic Method

Using coal gangue from Shuozhou, Shanxi as a single silicon source, superhydrophobic silica aerogel materials were prepared by acid-base one-step catalytic method. The effects of hydrochloric acid concentration and acid leaching temperature on alumina leaching, sodium hydroxide concentration and alkali leaching temperature on silica leaching, and the effects of hydrochloric acid concentration on aerogel under acid-base one-step catalysis were investigated by single factor leaching test. The results showed that: when hydrochloric acid concentration in acid leaching process was 3 mol/L, acid leaching temperature was 100 ℃, sodium hydroxide concentration was 3 mol/L, alkali leaching temperature was 80 ℃, and hydrochloric acid concentration in acid-base one-step catalytic process was 2 mol/L, the leaching rate of alumina and silica was 81.26% and 86.53%, respectively. The bulk density, specific surface area and hydrophobic angle of aerogels could be 0.04 g/cm3, 610.68 m2/g and 144.8°, respectively. This technology could provide an effective way for comprehensive utilization of coal gangue.