In the process of vegetable oil refining,large amounts of oily waste clay has been produced. If waste clay can not be effectively treated,the environment will be polluted and resources will be wasted. The regeneration of waste clay using solvent extraction was studied. Petroleum ether (90~120 ℃) and ethanol (95%) were used as the nonpolar and polar solvents,respectively. The waste clay was first extracted using petroleum ether(90~120℃) to obtain ideal component and then extracted with a mixed solvent of petroleum ether(90~120 ℃) and etha-nol (95%) to obtain nonideal component. The optimum regeneration conditions of waste clay are as follows:100 g waste caly is extracted by 100 mL solvent at 50 ℃,each extraction 3~4 times and each time 30~40 min. After treating,the total oil yield can be more than 28%,the specific surface area of the regenerated clay can be reached 150 m2·g-1,and other quality indexes such as decolorization rate,activity degree,free acid content,granularity, and moisture content can meet basic requirements,and adsorption properties of the regenerated clay recovers.%植物油精制过程产生大量含油废白土,如果不能有效处理会对环境造成污染,同时也造成资源浪费.采用溶剂抽提法对植物油精炼废白土进行再生研究,选用石油醚(90~120 ℃)为非极性抽提溶剂,95%乙醇为极性抽提溶剂,首先用石油醚(90~120 ℃)对废白土进行抽提,得到废白土中的理想组分,然后用石油醚(90~120 ℃)和95%乙醇的混合溶剂对废白土进行抽提,得到废白土中的非理想组分.确定了废白土再生的最佳工艺条件:溶剂用量为100 mL溶剂/100 g废白土,石油醚和乙醇的体积比为4:1,抽提温度50℃,抽提时间30~40 min,抽提次数以3~4次为宜.在上述条件下,废白土中总油分得率达到28%以上,再生白土比表面积达到150 m2·g-1,再生白土的脱色率、活性度、游离酸、粒度、水分等质量指标基本符合要求,吸附性能得到恢复.
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