应用PLS及BP神经网络定量分析汽油中甲缩醛含量

建立了采用中红外方法测定汽油中甲缩醛含量的方法。通过实验室配比一定体积分数的甲缩醛-汽油混合物作为研究的基础数据,利用傅里叶红外光谱仪测定不同比例甲缩醛-汽油混合物的谱图,分别建立偏最小二乘法(PLS)和BP神经网络的中红外谱图分析的校正模型。其中偏最小二乘法甲缩醛定量模型的相关系数R2为0.975 3,预测均方根误差(RMSEP)为0.121;BP神经网络法甲缩醛定量模型的相关系数R2为0.974 2,预测均方根误差(RMSEP)为0.132。该方法是一种操作简便、快速可靠的分析甲缩醛含量的方法。     

汽油中甲缩醛含量检测方法研究

探索了一种汽油中甲缩醛含量的测定方法。将试样用异辛烷溶解,以2-丁酮为内标物,使用非极性的HP-1聚甲基硅酮毛细管色谱柱、分流/不分流进样装置和FID检测器对试样中的甲缩醛进行气相色谱分离和测定。在优化的色谱条件下,甲缩醛的保留时间在C_4和C_5的保留时间之间,甲缩醛的定性和定量基本不受其他烃类的干扰。     

利用中学化学知识辨别调和汽油的简易方法

针对近期媒体上报道的调和汽油引发“熄火门”的事件,利用中学所学的有机化学相关理论知识对汽油中的N-甲基苯胺、甲缩醛和碳酸二甲酯三种调和组分进行快速辨别。方法简便快捷,贴近生活。     

中红外光谱法快速测定汽油中的碳酸二甲酯

运用日本岛津公司生产的傅里叶红外光谱仪对汽油及碳酸二甲酯进行扫描,获得不受其它组分干扰的碳酸二甲酯的特征吸收峰;并根据朗伯-比尔定律,对碳酸二甲酯进行定量分析。结果表明,傅里叶中红外光谱法可以准确测定汽油中的碳酸二甲酯,该方法具有分析速度快、重复性好、分析成本低等优点。     

甲缩醛的研究进展

概述了甲缩醛的基本合成方法,如甲醛和甲醇反应精馏制备甲缩醛、甲醇与多聚甲醛合成甲缩醛、二甲醚氧化法合成甲缩醛、二溴甲烷合成甲缩醛、甲醇一步氧化法合成甲缩醛,对某些合成方法进行了评述、成本分析和评价,并简单介绍了甲缩醛在各方面的应用以及发展前景。     

甲缩醛的研究进展

概述了甲缩醛的基本合成方法,如甲醛和甲醇反应精馏制备甲缩醛、甲醇与多聚甲醛合成甲缩醛、二甲醚氧化法合成甲缩醛、二溴甲烷合成甲缩醛、甲醇一步氧化法合成甲缩醛,对某些合成方法进行了评述、成本分析和评价,并简单介绍了甲缩醛在各方面的应用以及发展前景。     

中红外光谱法快速测定汽油中N-甲基苯胺

运用美国Thermo公司的傅里叶红外光谱仪对汽油及N-甲基苯胺进行扫描,获得不受其它组分干扰的N-甲基苯胺得特征吸收峰;并基于朗伯-比尔原理,对N-甲基苯胺进行定量分析。结果证明,傅里叶中红外光谱法可以准确测定汽油中N-甲基苯胺,方法具有分析速度快、重复性好、分析成本低等优点。     

中红外光谱法快速测定汽油中的乙酸仲丁酯

运用IR Affinity-1型傅里叶变换红外光谱仪对汽油及乙酸仲丁酯进行扫描,获得不受其它组分干扰的乙酸仲丁酯的特征吸收峰;并根据朗伯-比尔定律,对乙酸仲丁酯进行定量分析。结果表明,傅里叶中红外光谱法可以准确测定汽油中的乙酸仲丁酯,该方法具有分析速度快、重复性好、分析成本低等优点。     

浅谈调合油品中的苯胺物质等非常规汽油添加剂

本文概述了苯胺物质、乙酸仲丁酯、甲缩醛、碳酸二甲酯等非常规汽油添加剂的理化性质、对油品质量指标的影响、对车辆使用的影响及其合成和检测方法。     

GC-MS法检测车用汽油中的甲缩醛、碳酸二甲酯和N-甲基苯胺

车用汽油检测存在多种方式,GC-MS法是较为常见的一种,该方式具有检测精确率高、操作简单等优势。对GC-MS法检测车用汽油中的甲缩醛、碳酸二甲酯和N-甲基苯胺进行了研究。首先简单介绍了GC-MS法,继而设计了实验方案,最后通过对实验结果分析的方式,提出了文章研究结论。     

傅立叶近红外光谱法测定汽油中苯含量

介绍了傅立叶红外光谱测定汽油中苯含量的方法.以标准分析方法为参照,利用傅立叶红外光谱仪测定汽油的红外光谱,采用一阶微分和偏最小二乘法对汽油中的苯含量建立校正模型.该模型测定未知样品汽油苯含量的结果与标准分析方法的偏差符合标准方法的要求.     

近红外光谱在测定汽油重要指标中的应用

介绍了近红外光谱在汽油生产控制分析中的应用。在标准方法测定数据的基础上,采用偏最小二乘法建立了适合催化汽油和成品汽油测定RON、芳烃、烯烃的分析模型,并用大量试样对所建分析模型的可靠性进行了考察。结果表明,近红外光谱的测定结果与标准方法的测定结果有很好的一致性。近红外光谱技术的应用可以提高分析效率,降低分析成本,对装置的平稳运行和成品汽油的优化调和起到积极作用。     

Multivariate calibration in Fourier transform infrared spectrometry as a tool to detect adulterations in Brazilian gasoline

In the present work, Fourier transform infrared spectroscopy (FTIR) in association with multivariate chemometrics classification techniques was employed to identify gasoline samples adulterated with diesel oil, kerosene, turpentine spirit or thinner. Results indicated that partial least squares (PLS) models based on infrared spectra were proven suitable as practical analytical methods for predicting adulterant content in gasoline in the volume fraction range from 0% to 50%. The results obtained by PLS provided prediction errors lower than 2% (v/v) for all adulterant determined. Additionally, Soft Independent Modeling of Class Analogy (SIMCA) was performed using all spectral data (650-3700 cm⁻¹) for sample classification into adulterant classes defined by training set and the results indicated that undoubted adulteration detection was possible but identification of the adulterant was subject to misclassification errors, specially for kerosene and turpentine adulterated samples, and must be carefully examined. Quality control and police laboratories for gasoline analysis should employ the proposed methods for rapid screening analysis for qualitative monitoring purposes.     

合成二甲氧基甲烷技术研究进展

二甲氧基甲烷作为用途广泛的化工原料,其合成技术在不断创新与发展。根据反应原料和工艺流程的不同对二甲氧基甲烷合成技术进行了概述与简评,该技术包含甲醇与甲醛催化缩合制备二甲氧基甲烷、甲醇与多聚甲醛反应制备二甲氧基甲烷、甲醇一步法制取二甲氧基甲烷、离子液体电催化氧化甲醇制取二甲氧基甲烷、二甲醚氧化生成二甲氧基甲烷、二溴甲烷合成二甲氧基甲烷、合成气制备二甲氧基甲烷、甲醇与二氧化碳反应制取二甲氧基甲烷等。醇醛缩合制备二甲氧基甲烷仍是当前主流的生产工艺,甲醇一步法制取二甲氧基甲烷工艺因在环境和投资上有优势而被广泛研究,是最具工业化前景的新技术,该技术尚需突破的是兼具氧化还原性与酸性的双功能催化剂。     

轻汽油中醚含量的红外分析

采用红外光谱法分析催化裂化轻汽油醚化反应后的醚含量。用醚特征峰进行定性，与标准样曲线对照进行定量，此方法操作简单、省时、准确、重复性好。     

Gasoline classification by source and type based on near infrared (NIR) spectroscopy data

In this paper, we have tried to classify 382 samples of gasoline and gasoline fractions by source (refinery or process) and type. Three sets of near infrared (NIR) spectra (450, 415, and 345 spectra) were used for classification of gasolines into 3 or 6 classes. We have compared the abilities of three different classification methods: linear discriminant analysis (LDA), soft independent modeling of class analogy (SIMCA), and multilayer perceptron (MLP) - to build effective and robust classification model. In all cases NIR spectroscopy was found to be effective for gasoline classification purposes. MLP technique was found to be the most effective method of classification model building.     

Polyvinyl Butyral/Modified SiO2 Nanoparticle Membrane for Gasoline Desulfurization by Pervaporation

Pervaporation (PV) has many potential advantages in fluid catalytic cracking (FCC) gasoline desulfurization. The PV membrane performance was improved by incorporating SiO₂ nanoparticles in polyvinyl butyral (PVB). The coupling agent was used to enhance the compatibility between the inorganic phase and the organic phase to avoid the occurrence of film defects. Polyurethane membranes were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, and atomic force microscopy. To evaluate the PV performance, the real FCC gasoline was tested. The effects of the SiO₂ content, the operating temperature, and the active layer thickness on the PV performance of the PVB/SiO₂ membranes were investigated.     

Characterization of an HZSM-5/MnAPO-11 composite and its catalytic properties in the synthesis of high-octane hydrocarbons from syngas

Zeolite HZSM-5 is known to be active for the catalytic conversion of methanol into hydrocarbons, but its strong acidity and narrow channels may lead to high selectivity to aromatics, thus decreasing the quality of synthesized gasoline. In this work, an HZSM-5/MnAPO-11 composite was prepared via hydrothermal synthesis, and the catalytic synthesis of high-octane gasoline from syngas was studied in flow-type fixed-bed reactors. The catalysts were characterized employing X-ray diffraction (XRD), N₂ adsorption-desorption, ammonia temperature-programmed desorption (NH₃-TPD), scanning electron microscopy (SEM), energy-diffusive X-ray spectroscopy (EDS), atomic absorption spectrophotometry (AAS), and Fourier transformed infrared spectroscopy (FT-IR). Compared with HZSM-5 and a mechanical mixture of HZSM-5 and MnAPO-11, the HZSM-5/MnAPO-11 composite showed the highest gasoline yield and iso-paraffin selectivity due to the presence of more mesopores and moderate acid sites. The results provide new perspectives on the synthesis and application of composite molecular sieves in the production of gasoline.