考虑到需要从非食用油来源生产生物柴油,并考虑到ProsopisJuliflora(JF)被确定为埃塞俄比亚的高度入侵物种,这项研究的重点是生物柴油生产从一个可能的和有前途的替代原料。本研究的目的是通过酯交换分析埃塞俄比亚变体Juliflora基于生物柴油(JFB)的生产,通过探索各种工艺参数和官能团表征的影响进行优化(用GC-MS,FT-IR和NMR)包括流变行为,之前还没有报道。根据ASTM协议测试,已发现Juliflora的甲酯具有以下主要燃料性质:运动粘度(mm2/s)3.395,十六烷值52.9,酸值(mgkoh/g)0.28,密度(gm/ml)0.880,热值(MJ/kg)44.4,甲酯含量(%)99.8和闪点(°C)128,铜带腐蚀值1a,%FFA(游离脂肪酸)0.14。与柴油相比,粘度,密度,JFB的闪点高于柴油,虽然它具有相似的热值,但更重要的是高于大多数其他生物柴油。基于使用响应面方法的评估,甲醇浓度与催化剂负载量,温度,和反应时间被确定为最重要的影响工艺参数。观察到甲醇分解的最佳摩尔比为6:1,催化剂浓度为0.5wt%,在55°C下持续60分钟,生物柴油收率为65%。JFB在70分钟时的最大产量为130ml,在10分钟时的最小产量为40ml,这表明随着混合时间的增加,JFB产量倾向于增加到一定的时间限制。从2.5kg压碎的种子,观察到用己烷溶剂压碎的种子的最大粗油产量在3天内为480ml。傅里叶变换红外分析(FT-IR)揭示了在OH自由基上存在生物柴油所需的所有所需官能团,波数为3314.40cm-1,脂肪族甲基C-H在2942.48cm-1具有官能团(CH-3,-CH2-),和在2832.59cm-1处的亚甲基C-H。气相色谱-质谱仪(GC-MS)研究证实JFB中存在较高的酯含量,具有68.81%的较高不饱和度。脂肪酸,油酸的饱和度较低,为4.5%,而棕榈酸的阈值水平较低,为2.08%。流变试验表明,在生物柴油要求的范围内,剪切应力和粘度随温度的升高而降低,牛顿行为得到证实。JFB在低温下具有相当高的粘度和剪切速率。1HNMR(核磁共振)研究确定JFB具有必要的成分;并且脂肪族共振发生在1.5-3.0ppm的化学位移区域中。重要区域表明质子与杂芳族化合物结合,醛类,如13CNMR光谱所示。FT-IR的发现,GC-MS,1HNMR,和13CNMR是一致的,因此验证了JFB中大量官能团的存在。由于JFB拥有必要的生物柴油燃料属性,ProsopisJuliflora需要作为埃塞俄比亚有前途的生物柴油原料,以减轻进口燃料的负担,同时解决化石燃料燃烧释放的排放困难。
Considering the need for biodiesel production from non-edible oil sources and taking into account the fact that Prosopis Juliflora (JF) is identified as a highly invasive species in Ethiopia, this research focuses on biodiesel production from a possible and promising alternative feedstock. The objective of this study is to analyze Ethiopian variant Juliflora based biodiesel (JFB) production through transesterification, carry out optimization by exploring the effects of various process parameters and characterization of functional groups (with GC-MS,FT-IR and NMR) including rheological behavior, not yet been reported earlier. As per ASTM protocol testing, the methyl ester of Juliflora has been found to have the following main fuel properties: kinematic viscosity (mm2/s) 3.395, cetane number 52.9, acid number (mgkoh/g) 0.28, density (gm/ml) 0.880, calorific value (MJ/kg) 44.4, methyl ester content (%) 99.8, and flashpoint (°C) 128, copper strip corrosion value 1a,%FFA (free fatty acid) 0.14. When compared with those of diesel, the viscosity, density, and flash point of JFB are seen to be higher than those of diesel, although it has a similar calorific value but more importantly higher than most of the other biodiesels. Based on an assessment using response surface methodology, methanol concentration together with catalyst loading, temperature, and reaction time are determined to be the most important influencing process parameters. The best molar ratio for methanolysis was observed to be 6:1 with a catalyst concentration of 0.5 wt% at 55 °C for 60 min for biodiesel yield at 65%. The JFB maximum yield of 130 ml at 70 min and the minimum yield of 40 ml at 10 min demonstrate that as mixing time increases, JFB yield tend to increase up to a certain time limit. The maximum raw oil yield rom crushed seed with hexane solvent was observed to be 480 ml within 3 days from 2.5 kg of crushed seed. The Fourier transform infrared analysis (FT-IR) revealed the presence of all desired functional groups necessary for biodiesel on OH radicals at wave numbers of 3314.40 cm-1, Aliphatic methyl C-H at 2942.48 cm- 1 with a functional group (CH-3-,-CH2-), and methylene C-H at 2832.59 cm-1. The gas chromatography-mass spectrometer (GC-MS) study confirmed the higher ester content present in the JFB with a higher unsaturation level of 68.81%. The fatty acid, oleic acid has a lower saturation level of 4.5%, while palmitic acid has a lower threshold level of 2.08%. The Rheometer test showed that shear stress and viscosity reduced with increasing temperature within the range of biodiesel requirements, and the Newtonian behavior was confirmed. The JFB has a fairly high viscosity and shear rate at low temperatures. The 1H NMR (nuclear magnetic resonance) study established that JFB has a necessary ingredient; and aliphatic resonances occur in the chemical shift region of 1.5-3.0 ppm. Significant regions indicate protons bound to heteroaromatics, aldehydes, as shown by 13C NMR spectrum. The findings from the FT-IR, GC-MS, 1H NMR, and 13C NMR are in agreement thus validating the presence of numerous functional groups in JFB as such. Since JFB possesses the requisite biodiesel fuel attributes, Prosopis Juliflora need to be pursued as a promising biodiesel feedstock in Ethiopia for alleviating the burden of imported fuels while also addressing difficulties with emissions released by the combustion of fossil fuels.