枝孢霉菌对喷气燃料性质的影响及降解烷烃机理

Effect of Amorphotheca Resinae on the Properties of Jet Fuel and Mechanism of Degradation of Alkanes

以菌丝干重为指标,采用正交实验设计考察喷气燃料中特征真菌枝孢霉菌(A.resinae)的生长繁殖条件,及其生长过程中对喷气燃料总酸值、银片腐蚀等性能的影响;以喷气燃料替代物正十二烷构建枝孢霉菌生长体系,通过气相色谱、气-质联用仪考察枝孢霉菌生长规律,及正十二烷的降解率和降解中间产物,探讨正十二烷的降解机理,以考察枝孢霉菌影响喷气燃料性能的原因。结果表明:枝孢霉菌最佳生长繁殖条件为温度25℃、初始pH值8.0、钠元素质量浓度200.0 mg/L;枝孢霉菌能显著升高喷气燃料的总酸值,降低其表面张力,但对喷气燃料银片腐蚀实验结果和水反应实验结果没有明显影响;枝孢霉菌通过单末端氧化途径降解正十二烷,依次将其氧化为2-十二碳烯、2-十二碳烯-1-醇和2-十二碳烯酸。

Using the dry weight of mycelium as indicator,orthogonal experiments were carried out to optimize the growth conditions of the jet fuel dominant fungus Amorphotheca Resinae(A.resinae),and to study the effects of A.resinae on the total acid value and the silver strip corrosion of jet fuel.Taking n-dodecane as the model compound of jet fuel,the growth process of A.resinae,degradation rate,intermediates and mechanism of n-dodecane were investigated by GC and GC-MS.The experiments show that the optimal growth temperature of A.resinae is 25℃,the initial pH value is 8.0 and the sodium mass concentration is 200.0 mg/L.Moreover,it is found that the A.resinae significantly increases the total acid value and reduces the surface tension of jet fuel.However,it has no significant effect on the silver strip corrosion and water reaction of jet fuel.Lastly,we found that A.resinae degrades n-dodecane by a single terminal oxidation pathway,which oxidizes n-dodecane to 2-dodecene,2-dodecen-1-ol,and 2-dodecenoic acid.