نتایج جستجو برای: alkali catalyst
تعداد نتایج: 60055 فیلتر نتایج به سال:
The conversion of ethanol to 1,3-butadiene (1,3-BD) has been investigated over ZrO2 and ZnO containing magnesia silica oxides prepared by co-precipitation method at different Mg-to-Si molar ratios. The effect of reaction temperature and ethanol flow rate was investigated. The catalyst acidity was modified through the addition of alkali metals (Na, K and Li) to the final materials. Catalysts wer...
We report here the direct formation of the new chemical product trans-2,5-dihydroxy-3-pentenoic acid methyl ester from pentoses using tin-containing silicates as catalysts. The product is formed under alkali-free conditions in methanol at temperatures in the range 140–180 C. The highest yields are found using Sn-Beta as the catalyst. Under optimised conditions, a yield of 33% is achieved. Purif...
Oils with high content of free fatty acid (FFA) can be treated by acid esterification where an alcohol reacts with the given oil in the presence of acid catalyst. The investigated parameters include methanol to oil ratio, temperature and amount of catalyst. The optimum conditions for acid esterification which could reduce FFA content in the feedstock to less than 1.88% (acid value 3.76 mg KOH/g...
in this research work, we report the synthesis of macrocyclic diamides from the reaction of diesters and aliphatic diamines in the presence of caesium carbonate. it has been demonstrated that among the carbonate of alkali metals (li2co3, na2co3, k2co3 and cs2co3), cs2co3 appear to be the best catalyst for macrocyclization. diesters with different substitution patterns on the aromatic ring react...
Lignin is an important renewable source of phenolic products. In this study, alkali lignin was depolymerized to produce phenolic compounds. The effects of catalyst, solvent, reaction time, and reaction temperature on the yields of liquid products and volatile fractions were investigated in detail. Compared with the solvents water and octane, alcohols can significantly promote depolymerization o...
Ca poisoning behavior is inevitable for high-calcium content flue gas, so V2O5-WO3/TiO2 (VWT) and V2O5-WO3-CeO2/TiO2 (VWCeT) catalysts with different vanadium have been prepared the Ca-doped are compared in this manuscript. The result shows Ce addition can both promote NO conversion alkali resistance. Lower 0.1VWCeT catalyst promotes its oxidability modification more suitable low catalysts. tot...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید