Carbon Molecular Sieving (CMS) is a carbonaceous adsorbent, with uniform super-micro pores of 10 angstrom or less pore diameter. The most common application of CMS is to be used as an adsorbent for gas separation technology.
The production of high economical value (CMS) from lignocellulosic agriculture waste such as bagasse and corncobs (for the first time), has been successfully achieved. CMS samples were prepared through heat treatment processes, including carbonization, with the use of traditional furnace; physiochemical activation and chemical vapor deposition (CVD) (using LPG for the first time).
Moreover, trials to precipitate carbon from hydrocarbon gas (LPG) on carbonaceous samples from bagasse and corncobs were made to reduce the pore-diameter of carbonaceous materials, in which LPG was pyrolyzed to deposit fine carbon on the pore mouth of the activated carbon to yield CMS.
Experimental studies has shown the effects of different treatment parameters (temperature of activation and the time during carbonization stage) on average pore-diameter, total pore volume and average pore density of products obtained from bagasse and corncobs. The change, which took place in surface characteristics of CMS, is measured by Scanning Electron Microscope (SEM) and a Gas Sorption System using Brunauer-Emmett-Teller (BET) method.
The effect of carbonization temperature and carbonization time, as two important process parameters on microporosity development of CMS, is examined at (350, 750, 850 oC) and carbonization time of 4 and 12 hours.
The Scanning analysis of the CMS samples explored the successful deposition of LPG on pores of corncobs and bagasse-derived activated carbon and was found to yield a microporous CMS with a narrow pore size distribution.
The final products were microporous Carbon Molecular Sieving of successfully developed surface area with an average pore diameter of corncobs (0.41 μm x 10-2) and bagasse (0.58 μm x 10-2). In addition, the total pore volume for corncobs (6.76 cm3 g-1 ) has better capacity than for bagasse (2.76 cm3 g-1). The results obtained in this study have proved that a suitable choice of the activation procedure for corncobs and bagasse permits the production of cheap adsorbents with high sorption capacity toward gases.
The economics of producing CMS from agricultural waste showed that the return on investment (ROI), on using bagasse and corncobs for CMS production is around 63%. Thus, a high value CMS was obtained from a low value agricultural waste.
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