高吸附性能芦苇活性炭的制备方法研究

为实现白洋淀芦苇的有效利用,以白洋淀淀区芦苇(白苇)为原料,以KOH、K2CO3为活化剂,综合考虑制备过程中的剂料比、浸渍时间、活化温度、活化时间等因素的影响,通过正交试验,以碘吸附值和亚甲蓝吸附值综合作为吸附性能高低的评价标准,进行活性炭制备方法研究。结果表明:在以KOH为活化剂、剂料比为4∶1、浸渍时间36 h、850℃下活化1 h的条件下,制备的芦苇基生物质活性炭碘吸附值最高,亚甲基蓝吸附值较高;以K2CO3为活化剂、剂料比为3∶1、浸渍时间12 h、900℃下活化2 h的条件下,制备的芦苇基生物质活性炭有最高的碘吸附值和对亚甲蓝具有良好的吸附性。制备的生物质活性炭碘吸附值均高于国家活性炭一级品标准(1 000 mg/g),具备一定的实用性。

Ways for preparing reed activated carbon with high adsorption capacity

The present paper is aimed at tracing and examining the ways for improving the specific properties of the activated carbon content from the different raw reed material resources of Baiyangdian half nature-created and half human-force created lake reservoir.As is well known,Baiyangdian Reservoir enjoys rich reed resources both in abundance and nice quality in activated carbon,which has to be carefully traced and examined so as to understand their particular advantages for effective utilization on the basis of the sufficient command of their distinguished features.For example,the reed-based biomass activated carbon can be fully employed with KOH and K2CO3 as the activators,respectively and correspondingly,through the orthogonal experimental method to take the best advantages of their best qualities in preparing activated carbon with the different activators according to the iodine adsorption and the methylene blue adsorption by transforming the 4 situational levels of the agent/material ratio,the impregnation time,the specific activation temperature and the activation time into the most available advantages.The results of our study indicate that the optimal conditions for preparing the activated carbon with KOH as activators can be illustrated as follows:The advantages of the ratio of the agent to the material can be made to reach 4∶1,with the soaking time being 36 h,and the activation time-1 h at the temperature of 850℃.For,in so doing,the iodine adsorption standard ratio of the activated carbon content can be made to reach 1 216 mg/g,with the methylene blue adsorption ratio up to 225 mg/g.And,thus,the optimistic conditions for the activated carbon preparation with K2CO3 as activator can be stated as follows:the ratio of the agent to the material:3:1,with the soaking time being 12 h,for the activation time length of 2h at the temperature of 900℃.At the same time,the iodine adsorption rate of the activated carbon obtained can be made so high as to 1 072 mg/g,with the methylene blue adsorption rate being 60 mg/g.And,as the preparation of the activated carbon is concerned,2 methods can be suggested to follow:the preparation of the microporous activated carbon by the specific surface area of activation with the KOH activation method can be expected to reach 1 674 m2/g,with the proportion of micropores being 84%,at the volume of micropores of 0.610cm3/g.The specific surface area of the activated carbon prepared by K2CO3 activation method is 1 151 m2/g,with the proportion of micropores being 86%with the ratio of micropores being 0.418 cm3/g,which can prove that the micropore volume and micropore volume of the reed activated carbon prepared by KOH activation method may turn to be greater than those prepared by K2CO3 activation,whereas the adsorption performance of KOH activated carbon can be better than K2CO3 activated carbon.And,so,the adsorption properties of the activated carbon prepared by the 2 methods can be expected to reach the state-demanded standard and enjoy more popular practicability.