由铜渣浸出液制备二氧化硅气凝胶

Preparation of Hydrophobic Silica Aerogels from Leachate of Copper Slag

以铜渣硫酸浸出液为前驱体,三甲基氯硅烷(TMCS)、正己烷混合溶液为表面改性剂,通过净化、改性制备疏水性二氧化硅气凝胶。研究了水洗温度对凝胶中金属离子扩散效率的影响,以及不同TMCS添加量对气凝胶孔结构、孔径分布及表面性质的影响。结果表明,水洗温度40℃较合适;TMCS添加量为75%时所得气凝胶比表面积为822 m^2/g,平均孔径11.6 nm,密度0.24 g/cm^3,孔隙率88.7%,接触角123.5°,呈现出良好的疏水性和热稳定性。

With the leachate of copper slag as a precursor,a mixed solvent of trimethylchlorosilane（ TMCS） and n-hexane as the surface modification agent,hydrophobic silica aerogels were prepared successfully by purification and surface modification. Effects of the washing temperature on diffusion efficiency of metallic ions in the aerogel,different TMCS concentrations on pore structure,pore size distribution and surface properties of aerogel were all studied. Results showed that,at a proper washing temperature of 40 ℃,with the addition of TMCS at 75%,the prepared aerogels had a specific surface area of 822 m^2/g,with an average pore size of 11. 6 nm,density of 0. 24 g/cm^3,porosity of 88. 7%,contact angle of 123. 5°,presenting good hydrophobility and thermal stability.