Preparation And Adsorption Properties Of Biomass Carbon Aerogel Derived From Sweet Potato

With the development of China’s economy and the continuous improvement of consumption level,all kinds of organic dyes have been widely used in clothing and dyeing industries.The rapid expansion of factories has brought serious environmental problems,a large number of sewages containing organic dyes were discharged into nature and enter the body of animals and plants through ecological circulation,thus affecting people’s health.It has become an urgent problem to prepare an inexpensive,simple and efficient adsorbent without secondary pollution.Biomaterial carbon aerogel has been a hot research topic in recent years.Most of the reports are based on plant stem,fruit or extract of plants to prepare carbon aerogel.In this paper,sweet potato,a typical kind of tube root,was selected as raw material,and activated sweet potato biomass carbon aerogel（ASPCA）with high specific surface area was prepared by freeze-drying and one-step in situ activation.ASPCA was applied to dye adsorption and water treatment.The scheme has the advantages of low cost,simple technology and adaptability to industrial production and use.In this work,different pyrolysis temperature was screened to obtain the best product,and characterized by scanning electron microscope（SEM）,X-ray diffraction（XRD）,and cryogenic nitrogen gas adsorption/desorption（N₂adsorption/desorption）,Fourier transform infrared spectroscopy（FT-IR）,Raman spectroscopy（Raman）.The data of biomass aerogels was analyzed to explore the best reaction conditions and the impact of various preparation conditions on the final product,and developed the influence of the reasons.The results demonstrated that a higher carbonization temperature and the activation process contributed to the formation of porous structure of biomass carbon aerogels.The high temperature and the presence of KOH played an important role on the formation of micropores.In terms of adsorption,the adsorption properties of ASPCA for cationic dye rhodamine B and anionic dye alizarin red S was examined,the effect of initial concentration on adsorption amount,adsorption time on the adsorption behavior,adsorption temperature on the adsorption,ionic strength and the influence of p H on the adsorption quantity were studied.The adsorption kinetics and adsorption isotherm of the obtained data were studied to determine the adsorption mechanism of ASPCA.