Activated Coke Pore Structure/Functional Group Directional Control And Typical VOCs Adsorption And Removal Characteristics

Volatile organic pollutants（VOCs）are common carcinogens in indoor environment,such as formaldehyde,toluene and benzopyrene,which are continuously released from wood-based panels.In recent years,a large number of studies have been carried out at home and abroad on the release of indoor formaldehyde,but it is still difficult to achieve the sustainable and stable removal of indoor low concentration VOCs;In the process of coal-fired power generation,the traditional inorganic pollutants such as SO₂,NOx and particulate pollutants basically achieve ultra-low emission,and VOCs are important precursors of secondary organic aerosol（SOA）.The emission of a large number of VOCs has caused serious regional compound environmental pollution.The nano pore structure of activated coke,surface chemical functional groups and flue gas components have profound influence on the adsorption and conversion process of different VOCs molecules.In order to improve the adsorption capacity and adaptability of VOCs,it is important to deeply study the matching mechanism of adsorbent pore composition,surface polarity and different VOCs molecules,and develop activated carbon materials on this basis.In the third chapter,the effects of pore structure and surface polarity of carbon materials on the adsorption of dichloromethane and toluene were systematically studied.Six kinds of activated coke materials with typical pore classification were prepared by catalytic physical activation.The dynamic adsorption characteristics of dichloromethane and toluene were studied by using model activated carbon adsorbents with different pore structures and surface oxygen-containing characteristics.The results show that:（1）the hierarchical pore structure has a hierarchical occurrence effect on the adsorption of toluene and dichloromethane.（2）There is a polar occurrence mechanism of dichloromethane and toluene in the confined space of activated coke.By modifying the type and quantity of chemical functional groups on the surface of activated coke,the occurrence ability of different kinds of VOCs in activated coke channels can be effectively controlled.In the fourth chapter of this paper,model activated coke adsorbents with different pore size and N-doping were prepared by one-step catalytic activation method to explore the adsorption kinetics of dichloromethane and toluene.For the adsorption characteristics of dichloromethane and toluene,the results show that the microporous nitrogen doped activated coke has the highest adsorption performance of 75 mg/g for dichloromethane,while the graded porous activated coke has the highest adsorption performance of 225 mg/g for toluene.For the synergistic adsorption characteristics of dichloromethane and toluene,the results show that dichloromethane has a strong promoting effect on the adsorption of toluene by activated coke.This work not only provides important insights for the collaborative adsorption behavior of multi pollutants in porous coke,but also provides guidance for adjusting the porosity and surface chemical characteristics of activated carbon,so as to achieve efficient adsorption of various gaseous organic pollutants.