蔗渣灰制备SiO_(2)及其亚甲基蓝吸附性能  

Preparation of SiO_(2) from Bagasse Ash and Its Methylene Blue Adsorption Performance

作　　者：彭昭霞 李艳红[1] 梁光兵 张远琴 刘东辉[1] 刘晓波[1] 阳超琴[1] PENG Zhaoxia;LI Yanhong;LIANG Guangbing;ZHANG Yuanqin;LIU Donghui;LIU Xiaobo;YANG Chaoqin(College of Chemical Engineering,Kunming University of Science and Technology,Kunming 650500,China;College of Chemistry and Chemical Engineering,Central South University,Changsha 410083,China)

机构地区：[1]昆明理工大学化学工程学院,云南昆明650500 [2]中南大学化学化工学院,湖南长沙410083

出　　处：《环境科学与技术》2020年第10期77-84,共8页Environmental Science & Technology

基　　金：国家自然科学基金(21766013);昆明理工大学分析测试基金(2019T20070105)。

摘　　要：目前蔗渣灰等生物质灰的处理方式主要局限在填埋与堆积,尽管存在少数的一次应用,但在高附加值利用方向少有报道。为了解决这一问题,该文采用酸洗、碱提取的方法处理蔗渣灰制备蔗渣灰基SiO_(2)。使用XRF、XRD、FTIR、TEM、SEM、TG/DTG和BET对蔗渣灰基SiO_(2)进行了表征,并研究了蔗渣灰基SiO_(2)对亚甲基蓝的吸附性能。结果表明:利用酸洗、碱提取的方法制备的蔗渣灰基SiO_(2)为无定形态,其SiO_(2)质量分数达到96.11%,具有典型的SiO_(2)吸收峰特性;比表面积和总孔体积分别达到286.38 m^(2)/g和0.78 cm^(3)/g;亚甲基蓝的吸附等温线与Langmuir模型拟合效果较好;热力学计算数据表明吸附过程为自发放热过程;吸附动力学符合准二级动力学模型;吸附温度越低,亚甲基蓝的平衡吸附量越高,且常温下吸附效果较好,最大吸附量达到245.48 mg/g,蔗渣灰基SiO_(2)作为亚甲基蓝吸附剂具有较高的应用价值。At present,the treatment methods of bagasse ash and other biomass ash are mainly limited to landfill and accumulation.Although there are a few primary applications of bagasse ash,there are few reports on the use of high added value.In order to solve this problem,bagasse ash-based silica is prepared by treating bagasse ash by pickling and alkaline extraction.XRF,XRD,FTIR,TEM,SEM,TG/DTG and BET were used to characterize bagasse ash-based silica.At the same time,adsorption of methylene blue by bagasse ash SiO_(2) was studied.The results show that the bagasse ash-based SiO_(2) prepared by pickling and alkaline extraction is amorphous,and its SiO_(2) mass fraction reaches 96.11%,with typical SiO_(2) absorption peak characteristics.The specific surface area and total pore volume reached 286.38 m^(2)/g and 0.78 cm^(3)/g respectively.The adsorption isotherm of methylene blue fits well with the Langmuir model.Thermodynamic calculation data show that the adsorption process is a spontaneous heat emission process;the adsorption kinetics of methylene blue conforms to the pseudo-secondorder model.The lower the adsorption temperature,the higher the equilibrium adsorption capacity of methylene blue,and the adsorption effect is better at room temperature,with the maximum adsorption capacity reaching 245.48 mg/g.Silica has high application value as methylene blue adsorbent.

关 键 词：蔗渣灰 二氧化硅 亚甲基蓝 吸附 

分 类 号：X705[环境科学与工程—环境工程]