Preparation Technology Of Porous Carbon By Blend Carbonization Method

In recent years,with the further research and development of new material,porous carbon material has showing their unique advantage.Porous carbon material have good properties such as low density,high specific surface area and high porosity,which make porous carbon material have important application value in the fields of separation and filtration,catalyst carrier,heat insulation and muffling.In this study,With an eye to the stage that most of the carbon material only pursue higher specific surface area,but neglect their overall structure and strength performance.The aim is to develop a kind of porous carbon material with high strength,high porosity,controllable overall shape and certain specific surface area.Porous carbon material with high strength were successfully prepared from bitumen and bituminous coal by blending carbonization.Firstly,porous carbon raw material was prepared by pyrolysis,and then the porous carbon raw material was carbonized in vacuum sintering furnace under atmospheric argon protection conditions.Finally,KOH activation was carried out on porous carbon.The main results are as follows.(1)When the ratio of bitumen to bituminous coal is 1:2 and the particle size of raw material is 109 micron,the porous carbon raw material prepared by pyrolysis has compact structure,uniform porosity and high compressive strength.(2)During the pyrolysis of prefabricated billets,porous carbon raw material was prepared at a heating rate of 5℃/min,up to 500℃ and holding for 30 min.Its compressive strength can reach 13.63 MPa,BET specific surface area is 4.5～20 m2/g,and BET average pore diameter is 4.787 nm.(3)During the carbonization process of porous carbon raw material,the heating rate of carbonization is 5℃/min,the holding temperature and holding time of carbonization are 1000℃ and 2 h,respectively,to prepare porous carbon materials with uniform porosity and compact structure.The porosity is 49.30%～53.48%,the strength is 27.3 MPa,the specific surface area of BET is 86.00～108.24 m2/g,and the average pore diameter of BET is 2.775 nm.(4)During the activation of porous carbon,the optimum activation effect was obtained when the activation temperature was 800℃ and the mass fraction of KOH in the activation solution was 5%.The average compressive strength of the treated porous carbon was 9.5 MPa,the specific surface area of BET was 132.49～154.39 m2/g,and the average pore diameter of BET was 2.422 nm.