|
1,2 - dichloroethane (1,2-dichloroethane, abbreviated 1,2-DCE) is a typical representative of Chlorinated volatile organic compounds. The catalytic combustion Chlorinated volatile organic compounds in the purification technology research hotspot. This thesis attempts to synthesize one catalytically active transition metal oxide as the 1,2-DCE catalytic combustion catalyst, and from the catalytic activity, selectivity and stability aspects of the system investigated. Papers by oxidation precipitation (OP), three methods of co-precipitation method (CP) and microemulsion (ME) synthesis the series different Mn / Ce ratio of MnO of x -CeO 2 composite oxide catalyst. The three methods synthesis the MnO x -CeO 2 composite oxide in the catalytic combustion of 1,2-DCE than the plain of MnO x and pure CEO 2 better catalytic activity, selectivity and stability. In addition, the oxidation precipitation the synthesis of 0.5MnO x -CeO -OP sample is higher than the activity of the samples of the same proportion coprecipitation and microemulsion synthesis 1 temperature (T50) of the 2-DCE conversion was 50% at 350 ° C, the T90 of a temperature of 425 ° C, vinyl chloride selectivity of byproducts in the reaction during the heating process, is always lower than 6.2%. Samples of the synthesized MnO x MnO 2 physical phase is synthesized samples than the other two methods of Mn4 manganese species, indicating a high oxidation Manganese species beneficial catalytic combustion of 1,2-DCE. In addition, also inspected the the TiO 2 Al 2 O 3 and ZrO 2 carrier supported MnO x -CeO 2 -OP catalyst activity, showed better than non-load of MnO x -CeO to 2 -OP composite oxide high-temperature catalytic properties. Among them, the the carrier of MnO x TiO 2 -CeO 2 -OP composite oxide catalyst in the catalytic combustion of 1,2-DCE excellent catalytic combustion activity. Cr 2 O 3 and TiO 2 of CeO 2 ZrO 2 MnO x five metal oxide catalysts, catalytic combustion of 1,2-DCE T90 temperature turn of 375 ° C, 385 ° C, 425 ° C, 440 ° C and 460 ° C. TiO 2 with with known high catalytic activity Cr 2 O 3 considerable 1,2-DCE catalytic combustion activity, better than of CeO < sub> 2 , ZrO 2 , and MnO x . 1,2-DCE TiO 2 on catalytic combustion, only to produce vinyl chloride, chlorine, two chlorine byproducts and the selectivity is always less than 5.5% and 3%, better than the other Several catalyst, and good stability. 30% Cr 2 O 3 / TiO 2 the catalyst than the other of Cr 2 O load amount of the catalyst a more superior catalytic activity and selectivity. Airspeed 10000h-1 1 00000h-1, TiO 2 by airspeed great influence; airspeed 10000h-1 ,1,2-DCE The complete conversion of a temperature of 300 ° C.
|