Study On The Effect Of Microwave Discharge On The Process Of Activated Carbon Desulfurization And Denitrification

Light dependent resistor was used to convert the light of microwave-induced activated carbon discharged to voltage,monitored the change of discharge intensity in real-time during the test,using activated carbon as inducer,adsorbent and reductant,further studied the influence of microwave discharge intensity on desulfurization and denitration of activated carbon,by changing the main factors affect the discharge,microwave power,final temperature of activated carbon and its volume change,the relationship between discharge intensity,and CO production was obtained.By means of SEM,FT-IR,EDS,XPS and pore structure microparameters and other test methods to analyze the structure change and product identification,the main conclusions are as follows:?1?The particle size of activated carbon particles is larger,and the breakdown voltage between particles can be easily reached;When the particle size is certain,the average energy of the gas molecules increases as the temperature increases,the plasma density generated by collision ionization gradually increased,the discharge intensity increased;As the power increases,the more charge the polarization can gather,the greater the electric field E_i is between the particles,the more intense the ionization of activated carbon particles;The smaller the particle size,the stronger the microwave penetration ability,and the stronger the overall heating capacity of granular activated carbon,the molecular absorption radiation can vibrate-migrate more intensely,amorphous carbon structures are more likely to change.?2?In the process of removing NO,with the increase of the final temperature of activated carbon,the microwave power increases,while the discharge intensity increase,the denitration efficiency rise again,the CO generation increase,it shows that NO molecular collide with the plasma produced by discharge could obtain energy,NO molecules are transformed from the ground-state to the excited-state,catalyzing the C-NO reduction reaction;Under the condition of strong discharge,not only the reduction reaction of C-NO is catalyzed,but also the reaction of CO and NO is promoted,the quality of activated carbon for 2g,under the condition of 450?and 400W,the discharge intensity is the highest and the denitration is the highest.?3?By means of SEM and specific surface area,the pore structure of activated carbon was analyzed by pore size distribution,the honeycomb pore structure of activated carbon is destroyed after strong discharge,the physical adsorption performance gradually decreased,but the cutting edge of activated carbon increases,while the energy electron density increases,the discharge enhancement can maintain a high denitration efficiency for a long time.After weak discharge,the specific surface area increase by 43.3%and the micropore volume increase by 35.5%;FT-IR analyze shows the surface chemical adsorption capacity of activated carbon was enhanced first and then decreased,the chemical oxygen-containing functional groups on the surface of activated carbon were increased after discharge denitration,the NO molecule induced by discharge is converted to-C-NO₂ by-C-O adsorption to realize regeneration.?4?In the process of removing SO₂,with the increase of the final temperature of activated carbon,the microwave power increases,while the discharge intensity increase,desulfurization efficiency rise again,the CO generation increase,catalyzing the C-SO₂ reduction reaction,400W and 450?,the desulfurization quantity highest is 101.939 mg/g and 160.256 mg/g;When the quality of activated carbon increases,the discharge intensity is weak,and the desulfurization mainly depends on the pore structure and surface functional group adsorption of activated carbon.?5?SEM-EDS analysis of activated carbon after desulfurization shows under the condition of strong discharge,the sulfur element in the pore structure of activated carbon is increased;FT-IR analysis shows after desulfurization,most of the C-O functional groups were converted to-S=O compounds;The results of XPS analysis on the valence state of sulfur element showed that the microwave induced activated carbon discharge is mainly composed of S and chemical adsorption sulfur compound;Results of pore structure analysis shows after desulphurization,the content of activated carbon micropore is lower than the original,but it produces tiny holes smaller than 2 nm,the chemical reaction of microporous adsorption SO₂ is observed rapidly,the generated sulfur monomeric evaporative deposits are deposited in the mesoporous and macropores that are interlinked with the micropores,moreover,the new micropore structure which is conducive to adsorption of SO₂ gas molecules is extended.