The Study On Desulfurization And Denitrification Performance By Nano-V₂O₅/AC Catalyst

The emissions of SO2and NOXare increasing as the atmosphere of majorpollutants. Which emissions of SO2and NOXare accounted for about55%and50%because thermal power coal-fired. The paper aims to develop an economical andefficient catalyst to reduce concentration of sulfur and nitrogen, reduce pollution.This paper selected the optimum modified columnar activated coke (AC) as acarrier. The denitration performance of nano V2O5/AC catalyst with differentmorphologies was investigated. On this basis, the new catalyst was prepared byadding Fe2O3. The denitration performance of new catalyst was discussed. Furtherother aspects such as its optimal reaction conditions for denitrification, desulfurizationand denitrification combined performance and regenerate ability were explored.The desulfurization and denitrification performance of modified AC by threemethods such as HNO3, high pressure hydrothermal and NaOH, improved comparedwith virgin AC. Under the same conditions, the result of modified AC by HNO3wasbest. The desulfurization and denitrification rates were up to40.92%and36.41%respectively,22.27%and15.46%higher than virgin AC. The characterization resultsshowed that the surface area and micropore structure of modified AC had obviouschange. Then functional groups on its surface which is promoting desulfurization anddenitrification have increased.Spherical, linear and spindle-shaped nano-V2O5/AC prepared by hydrothermalmethod had good denitrification performance. The nano-linear V2O5/AC had the bestdenitration performent. The denitrification rate was up to57.41%when the loadcapacity of3wt%. Denitrification performance increased4.50%and3.33%comparedwith spherical, spindle-shaped V2O5/AC respectively. Adding1wt%Fe2O3on thebasis of1wt%V2O5, the denitration rate was57.82%. The optimum temperature was180℃for the denitration of catalyst. Water vapor inhibited the denitrition rate ofcatalyst. Denitration ratio of catalyst increased with decrease of airspeed. Withdecrease of the length of AC, the denitrification performance increased. When theairspeed of6000L/(Kg h) and a length of2~4mm, its denitrification rate was70.14%.O2, H2O, NO and NH3had a significant impact on desulfurization performance ofcatalyst. Two sections of combined desulfurization denitration experiments wereconducted with the fist paragraph temperature of120℃and the second of180℃.The desulfurization and denitrification reached to95.35%and56.76%respectively.After three times of regeneration, the desulfurization and denitrificationregeneration efficiency of catalyst is79.11%and66.42%respectively. When theregeneration temperature was500℃, regeneration performance was best. Whencombined catalyst regeneration, efficiency is87.76%and87.03%respectively.