The Study On Microwave Regeneration Of Waste Activated Carbon

Activated carbon is often used to adsorb pollutants because of its large specific surface area and good adsorption effect.However,the life of activated carbon is short,it will lose its activity and become waste after used,which will easily cause secondary pollution,so it is very necessary to study the regeneration of activated carbon.The microwave regeneration method,which has the advantages of simple operation,high selectivity,low energy consumption and short regeneration time,has attracted more and more attention.The effect of microwave power and amount of activated carbon on the regeneration effect was studied by microwave regeneration method.The ash content and pH value of activated carbon before and after regeneration were determined,and the surface structure and chemical properties of activated carbon before and after regeneration were studied by means of FT-IR,specific surface area,XRD,SEM,XPS,and Boehm titration.The results are as follows:1.The iodine value and methylene blue adsorption value of CA waste activated carbon after microwave regeneration were greatly improved,the ash content increased and the pH value increased,but the increase was not significant.A certain recovery of specific surface area,the increase of alkaline group and the decrease of acid group are consistent with the pH value.2.The direct microwave regeneration effect of 7-ACA waste activated carbon is not good,it needs advanced treatment,5% NaOH solution and waste activated carbon are mixed at 10:1 for 24 h,then washed to neutral and drying,after microwave regeneration,iodine value and methylene blue adsorption value can be greatly improved.It was found that the ash content of regenerated carbon increased more,which may be the reason for the adsorption of impurities.Alkaline groups of regenerated carbon increased significantly and acidic group decreased,which was consistent with the pH value of alkalinity.To sum up,the microwave regeneration method has remarkable effect on the regeneration of waste medicinal activated carbon,and has certain practical significance for the sustainable development of environment and economy.