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Selective de-activation of acid sites located near the outer surface of zeolite was examined using the catalytic cracking of silane (CCS) method. From FT-IR analysis, adsorption species of silane compounds on the acid sites of zeolite during calcination were investigated. Moreover, the effects of types of silane compounds on the changes in zeolite properties, including the amounts of adsorbed ammonia and benzene within zeolite, prior to and after CCS treatment, were examined. The CCS method using diphenylmethylsilane (DPM-silane) was effective in de-activating the acid sites located near the outer surface of ZSM-5 zeolite. Olefin synthesis from acetone was carried out using ZSM-5 zeolite catalysts. The ZSM-5 zeolite after the CCS treatment using DPMsilane exhibited high olefin selectivity as well as low aromatic selectivity.

Activated carbons were prepared from carbonized phenolic resins by steam-activation via a pre-treatment, that is mixing of raw materials with Ca(NO3)2·4H2O and acid-treatment after carbonization. This pre-treatment method has been reported as a method to produce mesoporous activated carbons. In the present work, three different novolak type phenol formaldehyde resins were synthesized under different molar ratio of formaldehyde (F) to phenol (P) (F/P = 0.3, 0.5, and 0.8) and were used as the precursors for activated carbons. It was confirmed that the pre-treatment method effectively enhances mesopores on activated carbons from synthesized phenolic resins prepared by F/P = 0.3 and 0.5, and their pore size distributions depended on the synthesizing conditions (F/P). Namely, it was found that by decreasing the F/P ratio of the precursor resin to the values lower than those usually adopted for commercial phenolic resin production, i.e., less than 0.5, activated carbons with developed mesopores could be obtained. The micropore developments of activated carbons were also influenced by F/P, and the influences were on the formation of pores larger than 0.40 nm. It was suggested that the thermoplastic nature of prepared resins (that can be changed by F/P) influence the porous properties of resultant activated carbons and the effect of the pre-treatments.

The effect of drying method used in the preparation of carbon gel microspheres was studied by comparing the porous properties of carbon cryogel microspheres (CCM) and carbon xerogel microspheres (CXM), which were respectively obtained using freeze drying and hot air drying. CCM were found to possess higher mesoporosity than CXM because freeze drying was effective to suppress the shrinkage of the mesopores during drying. On the other hand, the microporosity of the carbon gel microspheres was hardly influenced by not only the drying method but also the synthesis condition. Although the amounts of nitrogen and oxygen adsorbed were almost the same, the adsorption rate of nitrogen on both CCM and CXM possessing ultramicroporous surfaces was much larger than that of oxygen, which indicated the applicability of the carbon gel microspheres to adsorbents for pressure swing adsorption (PSA) of air. The relations between the temperature and the amount of oxygen adsorbed showed the adsorption characteristics...

Activated carbons were prepared from LFG (wastes generated during Lactic acid Fermentation of kitchen Garbage). Activated carbons were prepared by conventional steam activation and via the acid treatment prior to the steam activation. Porous properties of the prepared activated carbons were evaluated from nitrogen adsorption isotherms at 77 K. Activated carbons prepared by steam activation from LFG had much more mesopores than a commercial activated carbon, and had unique broad-shaped pore size distributions. It was evident from the ultimate analysis at each preparation stage of the carbons that the activated carbons prepared from LFG contain much nitrogen as carbonaceous materials. It was found that the burnoff of nitrogen during steam activation of LFG contributes to the formation of unique pore size distributions of the activated carbons. Activated carbons prepared via the acid treatment had not only more mesopores but also more micropores than the commercial activated carbon. It was suggested that LFG was useful as a resource for practical activated carbons, especially, for mesoporous activated carbons. It was also beneficial to apply the acid treatment to improve the porous properties of the prepared activated carbons.

Three series of experiments were conducted to collect information for the design of a commercial scale reactor for the production of low cost vapor grown carbon fibers (VGCFs). Firstly, the effects of reaction conditions on the yield of vapor grown carbon fibers were investigated using the newly developed liquid pulse injection technique. The examined conditions were the flow rate of the carrier gas, and the amount of the catalyst source injected into the reactor as a liquid pulse. Yields up to 40% were attained under optimized conditions. Secondly, VGCFs were continuously produced by intermittently injecting the catalyst source into the reactor (intermittent liquid pulse injection technique), and the effect of the intervals of the injections on the amount of VGCFs obtained was also investigated. VGCFs were successfully obtained using this method. Finally, the growth sequences of VGCFs were investigated using benzene, toluene and xylene as the carbon source. VGCFs were obtained from each carbon s...