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11.
Influence of catalyst calcination temperature on the catalyst characteristics and catalytic transesterification of Jatropha curcas oil for biodiesel production was studied by using sodium zirconate (Na2ZrO3) solid base catalyst. Na2ZrO3 catalysts were prepared by impregnation method followed by calcination at temperatures of 700, 800, and 900°C. The prepared catalysts were characterized by X-ray diffraction analysis, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy. Important parameters influencing the catalytic activity and fatty acid methyl ester yield were investigated. It was found that the increase in calcination temperature showed marked increase in activity due to the increased porosity and presence of tetragonal zirconia. Investigation of the reusability of the catalysts showed that the catalytic activity was retained even after five cycles of reaction.  相似文献   
12.
Biodiesel has emerged as one of the most promising renewable energy to substitute existing petroleum-derived diesel fuel being used in transportation sectors. Among the various feedstocks reported for biodiesel production, Moringa oleifera oil is becoming a promising replacement for conventional diesel fuel. Therefore, this work provides a comprehensive overview of the recent progress in biodiesel production from Moringa oleifera oil. The physicochemical properties, fatty acid composition of oil and methyl esters, oil extraction methods, esterification, and transesterification process, and purification methods employed in the biodiesel production have been discussed.  相似文献   
13.
Transesterification of a mixture of vegetable oils with methanol using metal oxide catalysts derived from snail shell (SS) for biodiesel production was investigated. The metal oxides obtained from calcined snail shells in the temperature range of 650°–950 °C and modified by loading different potassium salts were used as a catalyst in the process. The catalysts were characterized by FT-IR, XRD, SEM-EDS, XPS and TGA. Catalytic activities of developed catalysts were also tested by Hammet indicator method and ion exchange method. The best calcination conditions were observed at 850°C for 4 hours based on biodiesel yield. The KF loaded snail shell gave highest biodiesel yield of 98 ± 1% in a batch reactor with highest basicity (15.9 mmoles/g) and basic strength measured by Hammet method. The optimized reaction conditions were: reaction temperature 65°C, reaction time 3 hours, methanol to oil molar ratio 9:1 and catalyst concentration 3wt%. Leaching and reusability tests confirm the stability of the catalyst as it encounters only 3% of leaching and small changes in catalytic activity up to five runs in terms of biodiesel yield.  相似文献   
14.
生物柴油制备工艺影响因素的探讨   总被引:1,自引:0,他引:1  
介绍了生物柴油制备的基本工艺,着重阐述了催化剂、反应温度、反应时间、醇油比、水分以及游离脂肪酸含量对生物柴油制备的影响,并提出了生物柴油制备工艺今后的研究方向和开发前景。  相似文献   
15.
ABSTRACT

Poultry skin waste is considered to be a promising source of biodiesel. However, this source presents an environmental threat as it is being discharged into landfills without any treatment. We studied the feasibility of biodiesel production from poultry skin waste. Two-step extraction of lipids from chicken’s skin was developed and gave 97.5% yield using the optimum time and temperature. Esterification was then optimised to remove free fatty acids (FFA) where the ideal parameters were 65 °C during 30min with a molar ratio of methanol to oil of (1:3) and 1% of H2SO4. The third step was the transesterification which was performed using 60 °C and 300–600 rpm agitation for 1 h, with 1% basic catalyst and 1:3 (molar ratio) of methanol to oil. The biodiesel (FAME), was characterised using gas chromatography coupled with mass spectrometry (GC-MS) followed by chemical and physical analyses such as iodine number, acid number, flash point and cetane number. The total conversion was obtained using above conditions and most of the studied proprieties of produced biodiesel meet the EN14214 standard. This is an extremely encouraging result, offering a good source of biodiesel by valuing poultry skin waste.  相似文献   
16.
分析了各国废食用油脂的产生、回收和法规管理现状.重点通过分析废食用油脂物化性质,评价利用废食用油脂制造生物柴油的工艺特征和技术可行性.探讨了利用废食用油脂制造的生物柴油产品的品质和环境效益以及使用要求.同时分析了利用废食用油脂制造生物柴油的经济成本和存在的问题.  相似文献   
17.
废食用油脂作生物柴油原料的可行性分析   总被引:13,自引:0,他引:13  
分析了各国废食用油脂的产生、回收和法规管理现状。重点通过分析废食用油脂物化性质,评价利用废食用油脂制造生物柴油的工艺特征和技术可行性。探讨了利用废食用油脂制造的生物柴油产品的品质和环境效益以及使用要求。同时分析了利用废食用油脂制造生物柴油的经济成本和存在的问题。  相似文献   
18.
Generation of biodiesel from microalgae has been extensively investigated; however, its quality is often not suitable for use as fuel. Our investigation involved the evaluation of biodiesel quality using a native isolate Chlorella sorokiniana MIC-G5, as specified by American Society for Testing and Materials (ASTM), after transesterification of lipids with methanol, in the presence of sodium methoxide. Total quantity of lipids extracted from dry biomass, of approximately 410–450 mg g?1 was characterized using FTIR and 1H NMR. After transesterification, the total saturated and unsaturated fatty acid methyl esters (FAMEs) were 43% and 57%, respectively. The major FAMEs present in the biodiesel were methyl palmitate (C16:0), methyl oleate (C18:1), and methyl linoleate (C18:2), and the 1H NMR spectra matched with criteria prescribed for high-quality biodiesel. The biodiesel exhibited a density of 0.873 g cm–3, viscosity of 3.418 mm2 s?1, cetane number (CN) of 57.85, high heating value (HHV) of 40.25, iodine value of 71.823 g I2 100 g?1, degree of unsaturation (DU) of 58%, and a cold filter plugging point (CFPP) of –5.22°C. Critical fuel parameters, including oxidation stability, CN, HHV, iodine value, flash point, cloud point, pour point, density, and viscosity were in accordance with the methyl ester composition and structural configuration. Hence, C. sorokiniana can be a promising feedstock for biodiesel generation.  相似文献   
19.
Unrefined rubber seed oil contains high levels of free fatty acids and moisture, which make the conventional chemical catalyzed transesterification unsuitable. The method of enzyme catalyzed transesterification is well suited for biodiesel production from rubber seed oil as the enzymes are insensitive to the free fatty acids. In the present work, rubber seed oil was extracted from preserved rubber seed cake by mechanical means. The extraction process was designed and optimized through 24 full factorial design. Extracted oil was subjected to enzymatic transesterification using four different lipases to identify the best one for the purpose. Transesterification process was optimized by considering three influencing variables for biodiesel production viz. methanol/oil molar ratio, catalyst concentration (% w/v) and solvent content (% v/v). A 23 full factorial design was applied to design the experiments and optimize the biodiesel production. The interactive effects of the independent variables on biodiesel yield were analyzed and regression models were developed for each set of enzyme reactions. Among the four lipases, Thermomysis Lanugonosus Lipase was found to be the most suitable for the transesterification of rubber seed oil with a biodiesel conversion of 92.83% at a molar ratio of 4% and 5% (w/v) enzyme concentration in solvent free reaction medium.  相似文献   
20.
Biodiesel from waste cooking oil (WCO) requires antioxidants to meet oxidation stability specifications set forth in ASTM D6751 or EN 14214. In contrast, unrefined cottonseed oil (CSO), containing tocopherols and gossypol, produces biodiesel of higher oxidation stability. However, only a portion of these CSO endogenous antioxidants are suspected to be retained in biodiesel. Because the economics of biodiesel manufacturing rely upon inexpensive sources of triglycerides, emphasis was placed on developing improved alternative processing methods where WCO was the main source of methyl esters (WCOME) and CSO was used as a supplemental source of triglycerides and antioxidants in a 4:1 ratio. This study compared four processing methods for their ability to produce biodiesel of increased oxidative stability prepared from a 4:1 ratio of WCO:CSO. Two novel processing methods developed for this study utilise solvent properties of fatty acid methyl esters and glycerol to avoid additional chemical inventory for biodiesel processors. This study concludes that the two new processing methods resulted in biodiesel that had statistically significant improved oxidation stability when compared to two common industrial processing methods. Another significant finding is that high-shear homogenisation during transesterification reduced reaction time from the published one hour to 16 minutes.  相似文献   
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