The catalytic performance of KOH/mordenite has been studied for transesterification of palm oil using a batch reactor and a packed-bed reactor at 60 C and atmospheric pressure.The KOH/mordenite processed transesterifi...The catalytic performance of KOH/mordenite has been studied for transesterification of palm oil using a batch reactor and a packed-bed reactor at 60 C and atmospheric pressure.The KOH/mordenite processed transesterification in the batch reactor gave the highest methyl ester yield of96.7%under optimum conditions,while a methyl ester content over 94.5%was obtained in the packed-bed reactor.This comparison indicates that transesterification in a batch-type reactor gives a higher methyl ester yield than that of a continuous-flow reactor.Dealumination was found in the calcined catalysts and had a significant effect on the physical structure and chemical composition of the catalysts.Leaching of the potassium species was negligible,whereas depositing and washing of the reacted mixture with acetone on the catalyst surface were observed by FTIR.展开更多
KOH/CaO/C supported catalyst was prepared via incipient wetness impregnation and used in synthesis of biodiesel. First, the effects of carrier/active components mass ratio, calcination temperature and calcination time...KOH/CaO/C supported catalyst was prepared via incipient wetness impregnation and used in synthesis of biodiesel. First, the effects of carrier/active components mass ratio, calcination temperature and calcination time on catalytic activity were investigated aiming at biodiesel yield, and the optimal process conditions for preparation of KOH/CaO/C catalysts were: mass ratio of C/CaO was 4:6;KOH solution (mass concentration) was 25%;impregnation time was 24 h;drying temperature was 105°C and time was 4 h;calcination temperature was 500°C and time was 5 h. Then the complex catalysts prepared under the optimal conditions were applied to synthesize biodiesel, and the effects of dose of catalyst, reaction temperature, and reaction time on the yield of biodiesel were investigated. At last, the optimal process conditions for synthesis of biodiesel were concluded: methanol-oil ratio was 10:1;catalyst dose was 2% of that of soybean oil;reaction temperature was 65°C;reaction time was 5 h. The yield of as-prepared biodiesel could be 98%.展开更多
Biodiesel production from waste cooking oils over SO42-/Zr-SBA-15 catalyst was successfully carried out and investigated. SO42-/Zr-SBA-15 catalyst was prepared by one-step process using anhydrous zirconium nitrate as ...Biodiesel production from waste cooking oils over SO42-/Zr-SBA-15 catalyst was successfully carried out and investigated. SO42-/Zr-SBA-15 catalyst was prepared by one-step process using anhydrous zirconium nitrate as zirconium resource, and endowed with the strong Lewis acid sites formed by supporting the zirconium species onto the SBA-15 surface. The asprepared SOt2-/Zr-SBA-15 showed excellent triglyceride conversion efficiency of 92.3% and fatty acid methyl esters （FAME） yield of 91.7% for the transesterification of waste cooking oil with methanol under the optimized reaction conditions： the methanol/oil molar ratio of 30, the reaction temperature of 160 ℃, the reaction time of 12 h and 10wt% of catalyst. It was noticed that the as-prepared SOa2-/Zr-SBA-15 materials with the higher area surface of mesoporous framework and the surface acidity displayed excellent stability and reusability, maintaining high FAME yield of （74±1）% after seven runs of reaction.展开更多
Nano-solid-base catalyst K2O/γ-Al2O3 was prepared and adopted for the synthesis of biodiesel by transesterification of rapeseed oil with methanol. The particle diameter of the catalyst was about 50 nm, which was meas...Nano-solid-base catalyst K2O/γ-Al2O3 was prepared and adopted for the synthesis of biodiesel by transesterification of rapeseed oil with methanol. The particle diameter of the catalyst was about 50 nm, which was measured by transmission electron microscopy （TEM）. The variables affecting the yield of biodiesel during transesterification, such as mass ratio of KNO3 to γ-Al2O3, calcination temperature, calcination time, catalyst content, molar ratio of methanol to oil, reaction temperature and reaction time were investigated. The catalyst obtained by calcining a mixture of KNO3 and γ-Al2O3 （mKNO3/mγ-Al2O3 =70 %） at 600℃ for 3 h, was found to be the optimum one, which gave the highest catalytic activity in the reaction. With 3% （mcatalyst/moil） catalyst, when the transesterification was carried out at a molar ratio of methanol to oil of 12 ： ：1, a reaction temperature of 70℃, and a reaction time of 3 h, yield of 94% was achieved.展开更多
The preparation and regeneration conditions of the identified catalyst X/Y/MgO/?-Al2O3 with high catalytic activity were studied and optimized. The biodiesel was prepared by transesterification of Jatropha curcas see...The preparation and regeneration conditions of the identified catalyst X/Y/MgO/?-Al2O3 with high catalytic activity were studied and optimized. The biodiesel was prepared by transesterification of Jatropha curcas seed oil produced in Guizhou with methanol at its reflux temoerature in the presence of X/Y/MgO/?-Al2O3 . The pilot plant tests were carried out in a 100 L reaction vessel. Both average yield and fatty acid methyl esters (FAME) content reached more than 96.50% under the optimum reaction conditions of the pilot plant tests designed with an oil/methanol molar ratio of 1 : 10, catalyst concentration of 1.00%, and reaction time of 3 h at reflux temperature. In addition, analysis shows that the quality of biodiesel meets the standard EN 14214.展开更多
以尿素为沉淀剂制备了纳米Ca-Mg-Al水滑石,采用X射线衍射、傅里叶变换红外光谱和扫描电子显微镜对其进行了表征,以其煅烧后得到的纳米Ca-Mg-Al复合金属氧化物为固体碱催化剂,采用微水相超声波辐射协同固体碱催化小桐子油与甲醇进行酯交...以尿素为沉淀剂制备了纳米Ca-Mg-Al水滑石,采用X射线衍射、傅里叶变换红外光谱和扫描电子显微镜对其进行了表征,以其煅烧后得到的纳米Ca-Mg-Al复合金属氧化物为固体碱催化剂,采用微水相超声波辐射协同固体碱催化小桐子油与甲醇进行酯交换反应制备了生物柴油,并研究了催化剂的失活原因。实验结果表明,纳米Ca-Mg-Al水滑石的柱撑阴离子为CO_3^(2-),晶粒大小均匀,呈良好的层状结构。在超声波功率210W、占空比0.7、反应时间30min、温度60℃、甲醇与小桐子油摩尔比4∶1、催化剂用量1.5%(基于小桐子油的质量)的反应条件下,生物柴油收率达94.3%,精制后的生物柴油完全符合德国生物柴油标准DIN V 51606:1997。催化剂失活的主要原因是层状结构的塌陷和副产物甘油附着在催化剂表面,使用后的催化剂用乙醇洗去表面的甘油后,可连续使用12次。展开更多
基金supported financially by the National Metal and Materials Technology Center,Thailandthe Center of Excellence on Petrochemical and Materials Technology,Thailand
文摘The catalytic performance of KOH/mordenite has been studied for transesterification of palm oil using a batch reactor and a packed-bed reactor at 60 C and atmospheric pressure.The KOH/mordenite processed transesterification in the batch reactor gave the highest methyl ester yield of96.7%under optimum conditions,while a methyl ester content over 94.5%was obtained in the packed-bed reactor.This comparison indicates that transesterification in a batch-type reactor gives a higher methyl ester yield than that of a continuous-flow reactor.Dealumination was found in the calcined catalysts and had a significant effect on the physical structure and chemical composition of the catalysts.Leaching of the potassium species was negligible,whereas depositing and washing of the reacted mixture with acetone on the catalyst surface were observed by FTIR.
文摘KOH/CaO/C supported catalyst was prepared via incipient wetness impregnation and used in synthesis of biodiesel. First, the effects of carrier/active components mass ratio, calcination temperature and calcination time on catalytic activity were investigated aiming at biodiesel yield, and the optimal process conditions for preparation of KOH/CaO/C catalysts were: mass ratio of C/CaO was 4:6;KOH solution (mass concentration) was 25%;impregnation time was 24 h;drying temperature was 105°C and time was 4 h;calcination temperature was 500°C and time was 5 h. Then the complex catalysts prepared under the optimal conditions were applied to synthesize biodiesel, and the effects of dose of catalyst, reaction temperature, and reaction time on the yield of biodiesel were investigated. At last, the optimal process conditions for synthesis of biodiesel were concluded: methanol-oil ratio was 10:1;catalyst dose was 2% of that of soybean oil;reaction temperature was 65°C;reaction time was 5 h. The yield of as-prepared biodiesel could be 98%.
文摘Biodiesel production from waste cooking oils over SO42-/Zr-SBA-15 catalyst was successfully carried out and investigated. SO42-/Zr-SBA-15 catalyst was prepared by one-step process using anhydrous zirconium nitrate as zirconium resource, and endowed with the strong Lewis acid sites formed by supporting the zirconium species onto the SBA-15 surface. The asprepared SOt2-/Zr-SBA-15 showed excellent triglyceride conversion efficiency of 92.3% and fatty acid methyl esters （FAME） yield of 91.7% for the transesterification of waste cooking oil with methanol under the optimized reaction conditions： the methanol/oil molar ratio of 30, the reaction temperature of 160 ℃, the reaction time of 12 h and 10wt% of catalyst. It was noticed that the as-prepared SOa2-/Zr-SBA-15 materials with the higher area surface of mesoporous framework and the surface acidity displayed excellent stability and reusability, maintaining high FAME yield of （74±1）% after seven runs of reaction.
基金Supported by the National High-Technology Research and Development Program of China (863 Program) (2007AA100703)
文摘Nano-solid-base catalyst K2O/γ-Al2O3 was prepared and adopted for the synthesis of biodiesel by transesterification of rapeseed oil with methanol. The particle diameter of the catalyst was about 50 nm, which was measured by transmission electron microscopy （TEM）. The variables affecting the yield of biodiesel during transesterification, such as mass ratio of KNO3 to γ-Al2O3, calcination temperature, calcination time, catalyst content, molar ratio of methanol to oil, reaction temperature and reaction time were investigated. The catalyst obtained by calcining a mixture of KNO3 and γ-Al2O3 （mKNO3/mγ-Al2O3 =70 %） at 600℃ for 3 h, was found to be the optimum one, which gave the highest catalytic activity in the reaction. With 3% （mcatalyst/moil） catalyst, when the transesterification was carried out at a molar ratio of methanol to oil of 12 ： ：1, a reaction temperature of 70℃, and a reaction time of 3 h, yield of 94% was achieved.
基金supported by the Key Science and Technology Project of Guizhou(No.20076004).
文摘The preparation and regeneration conditions of the identified catalyst X/Y/MgO/?-Al2O3 with high catalytic activity were studied and optimized. The biodiesel was prepared by transesterification of Jatropha curcas seed oil produced in Guizhou with methanol at its reflux temoerature in the presence of X/Y/MgO/?-Al2O3 . The pilot plant tests were carried out in a 100 L reaction vessel. Both average yield and fatty acid methyl esters (FAME) content reached more than 96.50% under the optimum reaction conditions of the pilot plant tests designed with an oil/methanol molar ratio of 1 : 10, catalyst concentration of 1.00%, and reaction time of 3 h at reflux temperature. In addition, analysis shows that the quality of biodiesel meets the standard EN 14214.
文摘以尿素为沉淀剂制备了纳米Ca-Mg-Al水滑石,采用X射线衍射、傅里叶变换红外光谱和扫描电子显微镜对其进行了表征,以其煅烧后得到的纳米Ca-Mg-Al复合金属氧化物为固体碱催化剂,采用微水相超声波辐射协同固体碱催化小桐子油与甲醇进行酯交换反应制备了生物柴油,并研究了催化剂的失活原因。实验结果表明,纳米Ca-Mg-Al水滑石的柱撑阴离子为CO_3^(2-),晶粒大小均匀,呈良好的层状结构。在超声波功率210W、占空比0.7、反应时间30min、温度60℃、甲醇与小桐子油摩尔比4∶1、催化剂用量1.5%(基于小桐子油的质量)的反应条件下,生物柴油收率达94.3%,精制后的生物柴油完全符合德国生物柴油标准DIN V 51606:1997。催化剂失活的主要原因是层状结构的塌陷和副产物甘油附着在催化剂表面,使用后的催化剂用乙醇洗去表面的甘油后,可连续使用12次。
文摘热力学研究表明,大豆油在亚临界甲醇相具有良好的溶解性能,可解决常规酯交换过程中油脂与甲醇相间传质问题,而固体碱催化剂低温催化活性可解决超临界甲醇制备生物柴油过程中的高温问题。研究结果表明,在140℃、2 MPa、醇油摩尔比16∶1和反应时间30 m in条件下,K2CO3/A l2O3催化大豆油酯交换反应产物中脂肪酸甲酯含量可达90%以上。
