作　　者： ; ; ; ;

机构地区： 广西大学化学化工学院

出　　处： 《广西大学学报（自然科学版）》 2011年第3期379-384,共6页

摘　　要： 采用湿法将Ca(OH)2负载在活性白土的酸活性中心制备成碱性白土,考察了负载量和温度对吸附的影响,对负载得到的碱性白土进行了溶解度测定和表征,并通过油脂脱酸研究其化学吸附性能。实验结果表明,随着Ca(OH)2的负载量增加活性白土表面经历了3个吸附阶段:单分子层、双分子层及多分子层吸附,每个阶段的负载量为1.5～1.7 mmol/g,各个吸附阶段的过渡突变明显,活性白土表面的Bonsted酸和Lewis酸中心均具有吸附作用。制备温度升高,吸附的稳定性增强,产品的性能变好,性能优良的碱性白土需要在75℃以上制备。25℃以下制备的碱性白土其溶解度随温度的升高而升高,但75℃以上制备的碱性白土其溶解度随温度的升高而降低。碱性白土吸附油脂中的脂肪酸,每个阶段负载的氢氧化钙都参与反应,但每个氢氧化钙只能有一个氢氧根参加反应。 Alkaline clay was prepared by loading Ca（OH）2 on the acidic bits of activated clay using wet method.The effects of loading and temperature on the loading process of Ca（OH）2 were investigated,and alkaline clays prepared at different temperatures were characterized in order to figure out its loading mechanism through the characterization pictures and its solubility in water was measured.Alkaline clay was also used in edible oil deacidification to investigate its chemical adsorption ability.Results showed that there are 3 loading stages on the surface of activated clay with increased loading： monolayer,bilayer and multi-molecular layer adsorption,the loading of Ca（OH）2 of each stage is 1.5~1.7 mmol/g.There was a obvious protuberant from one stage to the next.Bonsted and Lewis acidic bits on the activated clay had adsorption activity.The stability of adsorption was getting better and better,so did the product performance with the increasing temperature.The alkaline clay of best performance should be prepared in more than 75 ℃.In the removal process of FFA,calcium hydroxide loaded on activated clay of each stage took part in the adsorption,but only a hydroxyl of a calcium hydroxide.

关 键 词： 氢氧化钙 活性白土 制备机理 脱酸

领　　域： [矿业工程] [矿业工程]