Japan Energy, Inc.

Micro and mesoporous molded activated carbon was fabricated from rice husk and beet sugar.The material properties of the rice husk and beet sugar based activated carbon were analyzed.The fabricated granular rice husk activated carbon and com. microporous granular coconut shell activated carbon were tested to remove aromatic sulfur compounds of benzothiophenes and dibenzothiophenes from com. kerosene.Fixed-bed flow tests were conducted, providing the breakthrough curves for benzothiophenes and dibenzothiophenes.The adsorption isotherms for benzothiophenes and dibenzothiophenes were also obtained in a batch-mode, correlating with the results of the fixed-bed flow test.Both the activated carbons were useful to remove them.The rice husk activated carbon showed a lower-selectivity for dibenzothiophenes. but a higher-selectivity for benzothiophenes. than the coconut shell activated carbon.

The desulfurization performance of solid superacid type adsorbent (sulfated alumina) for com. kerosene was evaluated on batch system and on continuous flow system.Adsorptive desulfurization using acidic adsorbent, especially sulfated alumina, is promising method for desulfurization of com. kerosene at moderate condition.The acid property seemed to effect on adsorption performance.Adsorbents combination of 4.1 l, 0.3 l of activated carbon supporting copper oxide and silver oxide and 3.8 l of Lewis acid type sulfate alumina in series, was evaluated for long term adsorptive desulfurization of com. kerosene without using hydrogen at ambient temperature at a flow rate of 105 cm³/h, which corresponds the flow rate of about 350 W scale of PEFC.Thiophene type and benzothiophene type sulfur compounds had not leaked for more than 2300 h.Dibenzothiophene (DBT) type sulfur compounds had not also leaked until 810 h, and it reached 0.02 mass ppm at 2000 h, and then 0.03 mass ppm at 2300 h.Especially C3-alkyl-DBT was difficult to be removed.

An activated carbon with a high microporosity and mesoporosity, as well as a high bulk d., was fabricated by activating the extrusion-molded precursor made from carbonized rice husk (RH) and beet sugar (BS) at 850°C in CO₂.The pore structure of the activated carbon based on the mixture of RH and BS (RHBSAC) was analyzed in relation to the bulk d.The extrusion molding was very useful to increase the bulk d.RHBSAC which was first activated for 1 h was immersed again in the BS syrup and then activated in CO₂ for 2 h.This two-step activation process provided both a high bulk d. (0.93 g/cm³) and a microporous and mesoporous structure (BET sp. surface area: 844 m²/g, total pore volume: 0.53 cm³/g, micropore volume: 0.29 cm³/g, and mesopore volume: 0.19 cm³/g).