Removal Of Tannic Acid From Aqueous Solution By Activated Carbon

Tannic acid(TA)has become a serious problem by polluting water because of its carcinogenic nature.Activated carbon(AC)is considered to be a promising adsorbent due to its high specific surface with tunnelable abundant pore structure,functional groups,high safety,and low-cost.However,the tannic acid adsorption on activated carbon is lack of systematic research.Hence,this work focuses on the comprehensive study of AC against the removal of tannic acid from water.The specific surface area of samples was investigated by argon adsorption and pore size distributions were calculated with carbon slit pore model based on adsorption branch.Furthermore,Raman spectroscopy and Fourier transform infrared spectroscopy were performed to confirm the bonding structure and nature of surface functional groups in given samples.Adsorption experiments were carried out as a function of initial tannic acid concentrations at p H=2 and 7.Adsorption data were modeled using the Langmuir and Freundlich adsorption isotherms.The TA adsorption capacities for all samples were relatively high at solution p H=2 and decreased with increasing the solution p H to 7.It was found that mesoporous AC is better than microporous AC for adsorbing tannic acid.It is hoped that such kind of valuable description warrants the selection of highly efficient AC material for the removal of tannic acid from water.