ZnCl_(2)活化法制备高岭土/玉米秸秆复合吸附材料的研究

Study on Preparation of Kaolin/Corn Straw Composite Adsorption Material by ZnCl_(2) Activation Method

以高岭土和玉米秸秆为原料,以ZnCl_(2)为活化剂,运用单因素法和正交实验法在不同活化剂浓度、不同高岭土与玉米秸秆的质量比、不同浸渍比条件下浸渍,再经电炉低温炭化、马弗炉煅烧制备高岭土/玉米秸秆复合吸附材料,使用T6新锐分光光度计表征其对亚甲基蓝溶液的吸附能力,并利用全自动比表面积及孔隙度分析仪对最优实验条件复合吸附材料进行表征。结果表明,最优实验条件是:ZnCl_(2)物质的量浓度0.25 mol/L、高岭土与玉米秸秆的质量比1:2、浸渍比4.5:1,在此条件下,制得的复合吸附材料对亚甲基蓝的吸附值是0.910 mg/g,比表面积为16.46 m^(2)/g,单点比表面积15.17m^(2)/g,微孔体积3.70×10^(-9) m L/g,微孔面积0.66 m^(2)/g,分析数据及吸附—脱附等温线得到,所制得的复合吸附材料孔隙结构并不均匀,存在多层吸附的现象,存在大量微孔及一定量的介孔。

In this paper,kaolin and corn stalk were used as raw materials,ZnCl_(2) was used as activator.Kaolin/corn stalk composite adsorption material was prepared by single factor method and orthogonal experiment under different activator concentrations,different mass ratios of kaolin to corn stalk and different impregnation ratios,and then carbonized in electric furnace at low temperature and calcined in muffle furnace.T6 new spectrophotometer was used to characterize the adsorption capacity of methylene blue solution,and the fully automatic specific surface area and porosity analyzer was used to characterize the composite adsorption material under the optimal experimental conditions.The results showed that the optimum experimental conditions were as follows:the concentration of ZnCl_(2) was 0.25 mol/L,the mass ratio of kaolin to corn stalk was 1:2,and the impregnation ratio was 4.5:1.Under these conditions,the adsorption value of methylene blue of the composite adsorbent was 0.910 mg/g,the specific surface area was 16.46 m^(2)/g,the single-point specific surface area was15.17m^(2)/g,the micropore volume was 3.70×10^(-9) mL/g,and the micropore area was 0.66m^(2)/g..According to the analysis data and adsorption-desorption isotherm,the pore structure of the prepared composite adsorbent is not uniform,and there is multi-layer adsorption,and there are a large number of micropores and a certain amount of mesopores.