Study On The Preparation And Properties Of Carbon Aerogel For Hot Gas Desulfurization

Energy is the basis of economic development,and the problem of energy consumption and environmental pollution is becoming more and more serious.Integrated gasification combined cycle power generation（IGCC）is an advanced clean coal power generation technology.It realizes the efficient combination and application of coal gasification technology and combined cycle,and has the characteristics of good environmental benefits and high power generation efficiency.The H₂S contained in crude gas will cause corrosion to the subsequent IGCC system,especially the gas turbine,resulting in equipment failure,affecting its working stability and reliability.The mercury contained in it is a heavy metal pollutant,and mercury is highly toxic,volatile and bioaccumulative.So before the coal gas enters the gas turbine,it is necessary to purify the gas and remove the sulfide and mercury.The key technology is the high temperature gas desulfurization technology to develop a suitable catalyst for high temperature gas desulfurization and dehydration.In this paper,a series of desulphurizing agents were prepared by ultrasonic impregnation by using the active component of the molybdenum base as the desulfurizer and using the carbon aerogel as the carrier.On the fixed bed activity evaluation device,the desulfurization and mercury removal activity test and stability test were carried out at the temperature range of 450-600℃.The study found that the specific surface area and pore structure characterization showed that the Mo/Cx desulfurizer maintains a large specific surface area and a good pore structure of the carbon aerogel support.Through X-ray diffraction（XRD）characterization,Mo/Cx desulfurizer contains MoO₃and MoO₂.The formation of MoO₂ is mainly due to the reduction of Mo⁶⁺by C under high temperature conditions.In the desulfurization activity test of Mo/Cx desulfurizer,Mo/C500desulfurizer has the best performance at 550℃,and the breakthrough sulfur capacity is 13.55g elemental sulfur/100g desulfurizer.The results of five cycle regeneration experiments at 550℃regenerations show that the Mo/C500desulfurizer has a good stable regeneration performance and maintains an initial sulfur content of 70%.The mercury removal activity test of Mo/Cx desulfurization agent,Mo/C500 desulfurizer mercury removal efficiency is higher than that of Mo/C200 and Mo/C800 desulfurizer under 500℃,reached 65%.Mo/C500desulfurizer reached the maximum reached 74%under 300℃,mercury removal efficiency can reach about 60%in the temperature range of 500-700℃.The 5 groups of stability tests of Mo/C500 had a good mercury removal efficiency of 60%-70%under the condition of 500℃,which could remove mercury in a long time.In conclusion,a Mo/C_x desulfurizer which has good desulfurization and mercury removal performance in high temperature environment is prepared,which provides a new research idea for high temperature desulfurization and mercury removal in the future.