榛子壳活性炭的制备及其应用研究

发布时间：2018-01-04 15:43

本文关键词：榛子壳活性炭的制备及其应用研究　出处：《沈阳农业大学》2017年硕士论文　论文类型：学位论文

【摘要】：活性炭作为一种优质吸附剂,广泛应用于医学制药、食品加工、工业制造及环境保护等各领域的除杂、脱色、脱臭。榛子壳的独特结构使其成为生产活性炭的良好原料。本实验以果壳废弃物榛子壳为原料,采用磷酸浸渍活化法制备活性炭,考察了磷酸质量分数、活化温度、活化时间、料液比等因素对活性炭吸附性的影响,在单因素的基础上,运用响应面法对活性炭制备工艺中磷酸质量分数、活化温度、活化时间、料液比各影响因素进行优化。结果表明,在磷酸质量分数48.5%、活化温度494℃、活化时间117min、料液比1:2条件下,榛子壳活性炭产品的碘值为1029mg·-1。采用扫描式电子显微镜(SEM)、傅里叶红外光谱(FT-IR)、比表面积及孔径分布分析仪等方法对最优条件下制备的活性炭进行表征,活性炭的比表面积可达到1364.00m2.g-1,平均孔径为3.17nm,总孔容为1.08cm3.g-1,表明榛子壳活性炭有较好的吸附效果,可作为一种环保型低成本吸附剂。以榛子壳活性炭作为吸附剂,对废弃食用油脂进行脱色研究。通过单因素和正交试验结果表明,活性炭加入量为10%,脱色时间为60 min,脱色温度为60℃,搅拌速率为250 rpm时,活性炭对废弃食用油脂的脱色率达到69.2%,脱色效果最佳。说明活性炭作为固体吸附剂对废弃食用油脂的脱色有一定效果。本试验研究了榛子壳活性炭对水中重金属离子Cr(Ⅵ)的吸附能力。结果表明,榛子壳活性炭用量为0.4g、pH值为2、接触时间为4h、溶液初始浓度为50mg.L-1时,对Cr(Ⅵ)的去除效果最好,吸附率达到98%。同时,利用动力学模型及等温吸附模型对榛子壳活性炭吸附水中Cr(Ⅵ)的实验数据拟合分析。结果表明,准二级动力学方程具有较高的拟合度,榛子壳活性炭对水中Cr(Ⅵ)的吸附过程符合准二级动力学模型。等温吸附模型所得拟合结果表明,Langumir等温吸附方程具有较高的拟合度,该吸附模型可以较好地描述吸附过程。综上,初步判断活性炭对Cr(Ⅵ)的吸附属于单层吸附。
[Abstract]:Activated carbon is an important adsorbent, widely used in medical and pharmaceutical, food processing, industrial manufacturing and environmental protection in various fields such as cleaning, bleaching and deodorization. The unique structure of hazelnut shell has become a good raw material for the production of activated carbon. In this experiment, the shell waste hazelnut shell as raw material, preparation of activated carbon by using phosphoric acid, the effects of phosphoric acid concentration, activation temperature, activation time, impact factors of liquid materials such as activated carbon, on the basis of single factor, the use of activated carbon in the preparation process of phosphoric acid mass fraction, activation temperature, activation time, response surface method, the effect of the ratio of material to liquid the factors were optimized. The results show that the concentration of phosphoric acid 48.5%, activation temperature of 494 DEG C, activation time 117min, ratio of material to liquid 1:2, hazelnut shell activated carbon iodine value was 1029mg -1. products using a scanning electron microscope (SEM), Fu Liyehong IR (FT-IR), specific surface area and pore size distribution analyzer and method of the optimal conditions of activated carbon were characterized, the specific surface area of active carbon can reach 1364.00m2.g-1, the average pore size of 3.17nm, general Kong Rong 1.08cm3.g-1, shows that hazelnut shell activated carbon has good adsorption effect, can be used as a kind of environmental protection low cost adsorbent. The hazelnut shell activated carbon as adsorbent to study the decolorization of waste edible oils and fats. The test results of single factor and orthogonal design showed that the dosage of activated carbon is 10%, decoloration time is 60 min, the decolorization temperature is 60 DEG C, stirring rate was 250 rpm, activated carbon decolorization of waste edible oils and fats the decolorization rate reached 69.2%, the best. Activated carbon as adsorbent for solid waste edible oils and fats have a certain effect. The study of hazelnut shell activated carbon on heavy metal ions adsorption capacity of Cr (VI). The results show that the hazelnut shell activated carbon dosage was 0.4g, pH value is 2, the contact time is 4h, the initial concentration of solution is 50mg.L-1, the Cr (VI) the best removal efficiency, the adsorption rate reached 98%. at the same time, the hazelnut shell activated carbon adsorption of Cr in water using kinetic model and adsorption isotherm model (VI) analysis the fitting of the experimental data. The results show that the quasi two level dynamic equation with higher fitting degree, hazelnut shell activated carbon in water Cr (VI) adsorption process followed the pseudo two order kinetics model. The adsorption isotherm model fitting results show that the Langumir isothermal adsorption equation has higher fitting degree, the adsorption model can be used to describe the adsorption process. In summary, the preliminary judgment of activated carbon on the adsorption of Cr (VI) belongs to monolayer adsorption.

【学位授予单位】：沈阳农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ424.1

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