Preparation And Application Of Microfibrous Entrapped Activated Carbon Composite

As an adsorption material with abundant porous structure and high specific surface area,activated carbon has been widely used in chemical industry, environmental protection, foodindustry, pharmaceutics, catalyst carriers and electrode materials, etc. In practice, the particlesize of activated carbon is about 1~4 mm in the process of filling fixed bed adsorber and fixedbed reactor, which led to greater resistance, low efficiency, slow adsorption and reaction rate,and this fixed bed adsorber or fixed bed reactor has small void. When the fluid passes, itcausesradial diffusion seriously and pressure drop greatly.In some applications, for example,canister technology, using the traditional particle packing materials and loading is difficult tomeet the actual demand. Therefore, developing a new microfibrous entrapped activatedcarbon composite to replace the traditional granular carbon in order to increase the overallperformance is a frontier and valuable research area. In this paper, preparation,characterization and application of microfibrous entrapped activated carbon composite wereinvestigated.Firstly,microfibrous entrapped activated carbon composite was prepared by the wetlay-up papermaking process and sintering process used metal fibers, granular activated carbonwith particles size at 80~100 mesh and wood cellulose as raw materials. The influences oftotal rotation, operating time, amount of water, sintering temperature, sintering time andquality of sintering pressed were investigated. The preparation parameters were optimized.The experimental results showed that microfibrous entrapped activated carbon composite hadexcellent performance in the conditions of 3000 r/min, working 10 min,operating time in lessthan 20 s, amount of water at 2 L, sintering temperature at 1050~1150℃, sintering time at15~30 min, quality of sintering pressed at 212 g. After sintering, surface area of activatedcarbon increased from 680 m2/g to 735 m2/g.Secondly, the application of treating carbon monoxide with microfibrous entrappedactivated carbon composite was investigated. The factors of reaction temperature, water vaporin carrier and gas velocity were discussed. The experimental results showed that carbonmonoxide on activated carbon impregnated with copper, chromium, silver had higher conversion efficiency about 40% at 80℃within the 25 min, no water vapor in carrier gas,velocity at 1 L/min when bed loaded granular activated carbon with particles size at 0.4 mm.Microfibrous entrapped activated carbon composite had less effect on oxidation of carbonmonoxide when loaded microfibrous composite at 10%. Microfibrous entrapped activatedcarbon composite had more effect on oxidation of carbon monoxide and increased from52.5% to 58.3% within 10 minutes when loaded microfibrous composite at 40%, comparingwith the traditional particle packing materials. When microfibrous complex bed loadedmicrofibrous composite at 100%, conversion of carbon monoxide was 32.3% within 10minutes, and carbon monoxide was not converted after 25 min.Finally, pressure drop of traditional bed loaded with different carbon particles size at40~60 mesh, 60~80 mesh and 80~100 mesh was discussed. Microfibrous complex bedsloaded microfibrous composite concentration at 10% and 40% were investigated for thepressure drop, comparing with the traditional particle packing materials loading particles sizeat 40~60 mesh. The experimental results showed that the smaller particle size has the greaterresistance. The bed loaded particles size at 40~60 mesh had the least resistance and the bedloaded particles size at 80~100 mesh had the greatest resistance. When the velocity reached1.5 L/min or 3 L/min, microfibrous complex bed loaded microfibrous compositeconcentration at 10% and 40% had the same pressure drop as the traditional particle packingmaterials bed loaded particles size at 40~60 mesh. When the velocity reached 6 L/min, 9L/min and 10.5 L/min, the pressure drop of microfibrous complex bed loaded withmicrofibrous composite concentration at 10% decreased 0.1~0.3 kPa and the pressure drop ofmicrofibrous complex bed loaded with microfibrous composite concentration at 40%decreased 0.3~0.6 kPa, comparing with the traditional particle packing materials bed loadedparticles size at 40~60 mesh.