http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Hussein Abou-Yousef,El Barbary Hassan 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.4
Promoted H-form zeolite was demonstrated as efficient catalyst for direct conversion of cellulose into hydroxymethylfurfural (HMF) in ionic liquid. Incorporation of alkali metal chlorides with zeolite was a novel approach to enhance the catalytic activity for the H-form zeolite. The reaction conditions were optimized for the highest HMF production by changing the alkali metal chloride/H-form zeolite catalytic system. Zeolite/LiCl system was the most effective catalyst used for production of HMF and other furan compounds. A proposed mechanism explaining the role of metal chlorides in increasing the acidity of system and accelerating the hydrolysis step of cellulose was explained.
Mun, Sung-Phil,Hassan, El-Barbary Mohamed 한국공업화학회 2004 Journal of Industrial and Engineering Chemistry Vol.10 No.5
Pine and poplar woods were liquefied using ethanol and phenol mixtures in the presence methanesulfonic acid (MSA) as catalyst, and the effects of the liquefaction variables were investigated. The woods were almost completely liquefied by replacing 10-13.3% of the total liquefying reagent with phenol. The optimum amounts of phenol for liquefaction depended on the lignin content of the wood and bark samples. A small amount of water addition (13.3% of the total liquefying reagent) was slightly effective for pine wood liquefaction, but it was not effective for poplar wood. To minimize the residue content, the amount of MSA was about 3.5 mmol for both woods, and a liquefaction temperature of at least 170℃ was required. The liquefaction follows a pseudo-first-order reaction in the early stage; it proceeded rapidly within 20 min for poplar wood and 30 min for pine wood at 180℃. The organic sulfonic acids, p-toluenesulfonic acid (PTSA) and MSA, and the mineral acid, sulfuric acid, were very effective acid catalysts for this liquefaction system, but hydrochloric acid was not. We found that lower alcohols other than ethanol could also be used successfully as liquefying solvents, but the polyhydric alcohols were less effective for the liquefaction.
Mun, Sung Phil,Hassan, El Barbary M. 한국공업화학회 2004 Journal of Industrial and Engineering Chemistry Vol.10 No.3
Pine (Pinus densiflora) and poplar (Populus alba × glandulosa) woods are liquefied by dioxanel polar solvent mixtures in the presence of mineral or organic sulfonic acid catalysts. Mixing 6.7- 40% of water with dioxane remarkably improved the liquefaction; this observation may be due to the hydrolysis effect and enhanced solubility of the liquefied material in the solvent. A similar improvement in the liquefaction also was observed when using other highly polar solvents, such as methanol, ethanol, and ethylene glycol (EG). Organic sulfonic acids, e.g., p-toluenesulfonic acid (PTSA), methanesulfonic acid (MSA), and naphthalenesulfonic acid (NSA), were slightly more effective as catalysts for the liquefaction than were mineral acids. More than 95% liquefaction was achieved within 30 min at 160 - 170℃, even when liquifying softwood.