Abstract In this paper, the accelerated degradation and oxidation of Jatropha biodiesel were carried out at 110 °C through the Rancimat method. The applicability of surface tension and UV absorbance in the fuel oxidation degree detection was studied through Gas Chromatography-Mass Spectrometer(GC-MS) and acid value titration. The analysis of experimental data demonstrated that the acid value, surface tension and density of Jatropha biodiesel increased by 551%, 3.8% and 0.91% following oxidation, respectively, while the UV absorption intensity at 230 nm increased nearly 2 times. Subsequently to oxidation, the correlations among surface tension, UV absorbance and acid value of Jatropha biodiesel were 0.9743 and 0.9702. Based on this fact, four prediction models for the degree prediction of fuel oxidation through surface tension and UV absorbance were proposed, while the cross-validation method was utilized. The test analysis finally determined that the two models were Logarithm model and Power model, while the RMESP and R values were 0.093, 0.9875, 0.0705 and 0.9928. Both the accuracy and correlation were high. The acid value prediction model based on surface tension was 7.8%, while the acid value prediction model based on UV absorbance was 3.8%. Both could accurately determine the oxidation degree of biodiesel.

中文翻译：

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表面张力和紫外吸收法快速测定生物柴油氧化降解的应用与分析

摘要 本文采用Rancimat法在110℃下对麻风树生物柴油进行加速降解和氧化。通过气相色谱-质谱联用仪(GC-MS)和酸值滴定法研究了表面张力和紫外吸光度在燃料氧化度检测中的适用性。实验数据分析表明，氧化后麻风树生物柴油的酸值、表面张力和密度分别增加了551%、3.8%和0.91%，而230 nm处的紫外吸收强度增加了近2倍。氧化后，麻风树生物柴油的表面张力、紫外吸光度和酸值之间的相关性分别为0.9743和0.9702。基于这个事实，提出了四种通过表面张力和紫外线吸光度预测燃料氧化程度的预测模型，同时利用了交叉验证方法。测试分析最终确定这两个模型为对数模型和幂模型，而 RMESP 和 R 值分别为 0.093、0.9875、0.0705 和 0.9928。准确率和相关性都很高。基于表面张力的酸值预测模型为7.8%，而基于UV吸光度的酸值预测模型为3.8%。两者都可以准确测定生物柴油的氧化程度。基于表面张力的酸值预测模型为7.8%，而基于UV吸光度的酸值预测模型为3.8%。两者都可以准确测定生物柴油的氧化程度。基于表面张力的酸值预测模型为7.8%，而基于UV吸光度的酸值预测模型为3.8%。两者都可以准确测定生物柴油的氧化程度。