Abstract:
In order to promote mass transfer and realize products separation from slurry, reaction performance of CuCr/CH3ONa catalyst used for the lowtemperature methanol synthesis was firstly examined in the bubble column slurry reactor with a flash column(BCSR/FC). The reaction system includes the reaction section of 39mm id. and 4800mm height and the enlarged section of 147mm id and 1200mm height in BCSR,FC of 147mm id. and 1640mm height and a slurry recirculating pump. The initial slurry was composed of the required amounts of sodium methoxide solution and CuCr catalyst and emulsifier OP10 as well as the balanced liquid xylene medium. The results showed that the BCSR/FC can be operated at 4.2MPa~4.6MPa,110℃~120℃ (reaction section)and 100℃~110℃(enlarged section),inlet gas velocity 0.35cm/s~0.40cm/s for BCSR, 0.25MPa~0.4MPa, 80℃~90℃ for FC and slurry recirculation rate of 50L/h. The results showed that the conversions of CO+H2, CO and H2 were decreased from their highest of 71.0%,79.1% and 67.5% to 17.8%, 35% and 12.1% during operation test over 100h respectively. The stability of the catalyst system is poor although its initial activity is quite high.This is probably due to the consumption of CH3ONa caused by the side reaction CH3ONa + HCOOCH3→CH3OCH3 + HCOONa. Liquid products were composed of DME of 1.23%, methanol of 79.52% and MeF of 19.25%. Selectivity of Methanol + MeF is more than 98%.Its yields were 0.168g/g cat·h based on all CuCr catalyst in the system and 0.336 g/gcat·h only based on the CuCr catalyst in BCSR.