Synthesis Of Metallic Oxide Using Plants As Templates And Their Adsorption Properties

ZnO and Al₂O₃ as important metal oxides have been widely used in various fields.Due to the structure of the materials,make them limited for the application.In this paper,to get samples with better structure and good adsorption performance,different natural plants were used as templates to prepare for biomorphic ZnO and biomorphic Al₂O₃.Variety of characterization methods were used to analyze the structure and morphology of the as perpared samples,including XRD,TEM,SEM,TG-DTA and so on,and adsorption performance was also studied for the products.（1）Preparation of biomorphic ZnO using legume straw as template and its adsorption property on Pb²⁺Using legume straw as template,zinc acetate solution as the precursor solution,impregnation method was used to make zinc ions growth on the surface of the legume straw.Biomorphic zinc oxide was prepared by a high-temperature calcination.The results of characterization shows: The as prepared biomorphic zinc oxide possessed a hierarchically baculiform structure which was formed by well-crystallized Zno grains orderly growth.The adsorption performance of lead ions was studied.Results showed that the as-synthesized samples has good adsorption performance.The amount of adsorbent on adsorption of Pb²⁺ increased with the increase of initial concentration,the temperature is not conducive to the adsorption process of adsorption process,and the adsorption process can be finished in 20 min.At the same time,through the adsorption isotherm and kinetics model fitting,It can be found that the adsorption process in line with the Freundlich adsorption isotherm equation,and the kinetic adsorption process of Pb²⁺ can be described with pseudo-second-order model preferably.（2）Preparation of biomorphic Al₂O₃ using nostoc flagelliforme in sea as template and its adsorption property on methylene blueIn this paper,nostoc flagelliforme in sea as template,traditional impregnation-calcination method was used to prepare the biomorphic alumina and its adsorption performance on methylene blue dye was also studied.Characterization and adsorptionexploration showed that as-prepared samples retained the original biological templates morphology in a certain extent.Compared with reagent alumina,its adsorption properties have been obviously enhanced.When the methylene blue solution concentration rises,the adsorption quantity on methylene blue increases,the change of pH have an obvious influence on the adsorption properties;At the same time,the adsorption process in accordance with the Freundlich isotherm adsorption equation,the pseudo-second-order model can better describe the process of adsorbent adsorption of methylene blue.（3）Preparation of biomorphic Al₂O₃ using piny flower grains as template and its adsorption property on methylene blue.In this paper,the traditional template-impregnation method and impregnationhydrothermal method were used to prepare flowers like alumina with piny flower grains as template.The results of characterization and adsorption properties showed that the structure of as-prepared biomorphic alumina was formed by nano alumina chips assembled into flowers shape,the best adsorbent dosage is 0.6 g/L,when pH is 4,adsorption performance is best.Heating can increase its adsorption properties,adsorption isotherm model fitting results show that the Freundlich can better describe the adsorption process.Optimal adsorption time is 180 min,adsorption process conforms to the pseudo-second-order model.