FTIR光谱在润滑油污染物定量监测中的应用研究  

Application of FTIR Spectrum in Quantitatively Monitoring Oil Contaminants

作　　者：李婧[1] 田洪祥[1] 孙云岭[1] 明廷锋[1] 盛晨兴 LI Jing;TIAN Hong-xiang;SUN Yun-ling;MING Ting-feng;SHENG Chen-xing(College of Power Engineering,Naval University of Engineering,Wuhan 430033,China;Key Laboratory of Marine Power Engineering & Technology(Ministry of Transport),Wuhan University of Technology, Wuhan 430063,China;Reliability Engineering Institute,National Engineering Research Center for Water Transportation Safety,Wuhan 430063, China)

机构地区：[1]海军工程大学动力工程学院,湖北武汉430033 [2]武汉理工大学船舶动力工程技术交通行业重点实验室,湖北武汉430063 [3]国家水运安全工程技术研究中心可靠性工程研究所,湖北武汉430063

出　　处：《光谱学与光谱分析》2019年第11期3459-3464,共6页Spectroscopy and Spectral Analysis

基　　金：NSFC-浙江两化融合联合基金项目(U1709215)资助

摘　　要：柴油机润滑油在使用过程中,会受到水份、柴油或冷却液等的污染,受高温或燃烧室气体的作用还会产生氧化、硝化、磺化等产物,严重时,这些污染和产物可导致装备的失效。在用润滑油分析能可靠地反映其工作状态,从而确定最佳换油时机和故障源,以避免柴油机在使用过程中产生异常磨损及腐蚀等问题。目前的传统方法,是用卡尔菲休法测定石油产品中水份,气相色谱法测定柴油机油中的柴油稀释剂,因分析时间长和费用高等因素影响其普及应用。傅里叶红外(FTIR)光谱法从分子水平分析润滑油,从而能更有效地监测在用油,由于光谱的复杂性,目前尚不普及。通过在实验室条件下配置多种污染程度的油液样,分别为润滑油含水份百分比浓度为0.11%,0.22%,0.44%和0.88%的油样;润滑油在230℃下的氧化时间为299,323,371和395h的油样;润滑油被柴油稀释的质量百分比浓度为1.5%,3%,6%和12%的油样;润滑油含乙二醇质量百分比浓度为0.1%,0.2%,0.4%和0.8%的油样,包括配置的润滑油油样共计20个。实验采用安捷伦Agilent Cary 630红外光谱仪,使用100μm厚的液体池,防潮ZeSe型配置的光谱范围为4 000~650cm-1。分析了所有油样,获得了FTIR光谱图,确定了水、氧化产物、柴油、乙二醇污染所对应的特征波段范围分别为3 150~3 500,1 670~1 800,745~755和1 030~1 100cm-1;监测参数包括特征波段的实测中心点、左边界、右边界、左基线、右基线等。建立了一种在用润滑油污染物定量分析模型,通过水份、柴油、乙二醇的污染比例和峰面积,在230℃下的氧化时间与峰面积分别建立拟合方程,水、柴油、乙二醇含量百分比与对应峰面积的相关系数分别为0.977 9,1.000 0和0.989 5,氧化时间与对应峰面积的相关系数为0.999 6。分析计算预测值与实际值的相对误差可知:水份和乙二醇在含量大于0.2%时,预测的最大相对误差为10%;氧化Marine diesel engine oil in service will be contaminated by water,fuels,coolants,and other degradation products such as oxidation,nitrification and sulfonation,which can also be produced under the influence of high temperature or combustion chamber gas.In serious cases,these contaminants and products can lead to the failure of equipment.Analyzing the used oils can reveal its condition,therefore determine the optimum oil changed period and fault source,and avoid the abnormal wear and corrosion of diesel engine during operation.At present,the traditional methods are as follows that the coulometric Karl Fischer titration be used to measure the water content in oils and gas chromatography to determine the fuel dilution.Due to long time and high cost for oil analysis,these two methods mentioned above are not widely used in monitoring oils.For analyzing the lubricating oil at the molecular level,Fourier infrared(FT-IR)spectroscopy can be used to monitor oil more effectively.Unfortunately, it is not yet widely used at present because of the complexity of the spectrum.The oil samples sum up to 20,which are contaminated by water,fuel,ethylene glycol coolant,high temperature oxidation as well as new oil.Water concentrations in oil are 0.11%,0.22%,0.44%and 0.88%.The durations of high temperature for oil oxidation are 299,323,371and 395h.The fuel dilutions of oil are 1.5%,3%,6%and 12%.Ethylene glycol coolant concentrations in oil are 0.1%,0.2%,0.4%and 0.8%. The oil samples were analyzed by the Agilent Cary 630FT-IR with a factory set pathlength of 100microns and with the spectral range of 4 000~650cm^-1.FT-IR spectra of all oil samples were obtained with FT-IR spectrometer.It is determined that the corresponding characteristic band ranges of water,oxidizing products,fuel dilutions and ethylene glycol coolant respectively are 3 150~3 500,1 670~1 800,745~755,1 030~1 100cm^-1.Monitoring parameters of FT-IR spectra include center point,left boundary,right boundary,left baseline and right baseline.A quantitative analysis model fo

关 键 词：在用润滑油 工况监测 FTIR光谱 船用柴油机 燃油稀释 

分 类 号：O657.3[理学—分析化学]