CAJ | 학술논문

诱导期是评价汽油氧化安定性的重要指标。国内燃油市场汽油流通量较大，但目前仍采用传统GB/T8018-87方法测定汽油诱导期，工序繁琐，耗时较长，难以实现对每批油品及时检测，无法满足汽油品质监管需求。为此，本文提出了一种采用傅里叶变换衰减全反射红外光谱（ATR-FTIR）测定汽油诱导期的快速分析方法。设计和集成了一种采用傅里叶变换衰减全反射红外光谱的智能型专用燃油品质快速分析系统，集光谱采集、数据处理、显示与存储等于一体。设计的测样附件由9次反射的衰减全反射（ATR）硒化锌晶体和带密封的不锈钢盖组成，具有光程恒定，注样和清洗方便等优点。研究了光谱扫描次数和重复装样次数对光谱信噪比的影响规律，确定了最佳扫描次数为15次，装样次数为4次。从京津地区收集64个不同牌号、不同生产时间的汽油样本，采用GB/T8018-87方法测定其诱导期数值作为建模参考数据。使用该系统采集油样红外光谱。对光谱数据进行均值中心化、一阶求导预处理，采用偏最小二乘PLS方法将汽油红外光谱与其诱导期数据进行关联，建立车用汽油诱导期定量校正模型，其决定系数（R2）0.897，校正标准偏差（SEC）68.3min，预测标准偏差（SEP）91.9min。模型专用燃油品质快速分析系统预测汽油诱导期的相对偏差均小于5％，满足GB方法重复性允差要求。与传统GB方法相比，该方法操作简单，分析速度快，单个样本检测仅需3min，对油品储运及销售过程中快速准确品质监管有积极意义。
유도기시평개기유양화안정성적중요지표。국내연유시장기유류통량교대，단목전잉채용전통GB/T8018-87방법측정기유유도기，공서번쇄，모시교장，난이실현대매비유품급시검측，무법만족기유품질감관수구。위차，본문제출료일충채용부리협변환쇠감전반사홍외광보（ATR-FTIR）측정기유유도기적쾌속분석방법。설계화집성료일충채용부리협변환쇠감전반사홍외광보적지능형전용연유품질쾌속분석계통，집광보채집、수거처리、현시여존저등우일체。설계적측양부건유9차반사적쇠감전반사（ATR）서화자정체화대밀봉적불수강개조성，구유광정항정，주양화청세방편등우점。연구료광보소묘차수화중복장양차수대광보신조비적영향규률，학정료최가소묘차수위15차，장양차수위4차。종경진지구수집64개불동패호、불동생산시간적기유양본，채용GB/T8018-87방법측정기유도기수치작위건모삼고수거。사용해계통채집유양홍외광보。대광보수거진행균치중심화、일계구도예처리，채용편최소이승PLS방법장기유홍외광보여기유도기수거진행관련，건립차용기유유도기정량교정모형，기결정계수（R2）0.897，교정표준편차（SEC）68.3min，예측표준편차（SEP）91.9min。모형전용연유품질쾌속분석계통예측기유유도기적상대편차균소우5％，만족GB방법중복성윤차요구。여전통GB방법상비，해방법조작간단，분석속도쾌，단개양본검측부수3min，대유품저운급소수과정중쾌속준학품질감관유적겁의의。
A new method is proposed for the fast determination of the induction period of gasoline using Fourier transform atten-uated total reflection infrared spectroscopy (ATR-FTIR) .A dedicated analysis system with the function of spectral measure-ment ,data processing ,display and storage was designed and integrated using a Fourier transform infrared spectrometer module and chemometric software .The sample presentation accessory designed which has advantages of constant optical path ,conven-ient sample injection and cleaning is composed of a nine times reflection attenuated total reflectance (ATR) crystal of zinc sele-nide (ZnSe) coated with a diamond film and a stainless steel lid with sealing device .The influence of spectral scanning number and repeated sample loading times on the spectral signal-to-noise ratio was studied .The optimum spectral scanning number is 15 times and the optimum sample loading number is 4 times .Sixty four different gasoline samples were collected from the Beijing-Tianjin area and the induction period values were determined as reference data by standard method GB/T 8018-87 .The infrared spectra of these samples were collected in the operating condition mentioned above using the dedicated fast analysis system .Spec-tra were pretreated using mean centering and 1st derivative to reduce the influence of spectral noise and baseline shift .A PLS cal-ibration model for the induction period was established by correlating the known induction period values of the samples with their spectra .The correlation coefficient (R2 ) ,standard error of calibration (SEC) and standard error of prediction (SEP) of the model are 0.897 ,68.3 and 91.9 minutes ,respectively .The relative deviation of the model for gasoline induction period predic-tion is less than 5% ,which meets the requirements of repeatability tolerance in GB method .The new method is simple and fast . It takes no more than 3 minutes to detect one sample .Therefore ,the method is feasible for implementing fast determination of gasoline induction period ,and of a positive meaning in the evaluation of fuel quality .