Organic lead compounds in vehicle exhaust

Species-specific measurements of the five tetraalkyllead compounds used in gasoline and their intermediate decomposition products, the tri- and di-alkyllead species, have been made in vehicle exhaust fumes. Under normal engine running conditions 0.3–3% of the lead emitted in exhaust is as an organic compound, but cold, choked engines emit proportionally much larger amounts of alkyllead. Alkyllead is emitted in both the gas and the aerosol phases.     

改性聚丙烯酸高级酯的合成及其降凝效果的考察

用酯化和热聚合同时进行的方法合成了聚丙烯酸高级醇酯（PAE），并对其进行改性，得到改性聚丙烯酸高级酯（MPAE），在实验室评价了MPAE对几种0#柴油的低温流动性能的改进效果。结果表明，该工艺路线产品的收率几乎达到100％，成本低。并且，改性后的聚丙烯酸高级酯在较宽的分子量范围内具有较好的降凝效果；相比之下，改性之前聚丙烯酯高级酯只在很窄的分子量范围内具有降凝效果。与其它柴油降凝剂相比，MPAE对柴油具有良好的感受性，一般能降低柴油冷滤点3℃－6℃，凝固点降幅在10℃－12℃左右，具备了工业化价值。     

Dearomatization, cetane improvement and deep desulfurization of diesel feedstock in a single-stage reactor

Hydrotreating of light cycle oil over CoMo/Al₂O₃, NiMo/Al₂O₃ and NiW/Al₂O₃ catalysts has shown that the type of catalyst has a critical influence on the composition and properties of the product. Divergent effects of aromatics content and molecular weight on the cetane index by these catalysts occurred. Data show that it was not possible to obtain a diesel product that meets stringent specifications using one type of catalyst in a single-stage reactor even under severe operating conditions.     

Differentiation between weathered kerosene and diesel fuel using automatic thermal desorption‐GC‐MS analysis and the likelihood ratio approach

The identification of various petroleum products, which can be used to set a fire, is one of the tasks of a forensic examination. One of the analytical problems is differentiation of weathered kerosene and diesel fuel samples, analysed with automatic thermal desorption‐GC‐MS technique, because there are only small quantitative differences in their chemical compositions. The presented research showed that the observed differences in the analysed samples of kerosene and a diesel fuel, which were weathered at the time of burning, were systematic and significant. Therefore, it was possible to distinguish them on the basis of information about the relative content of n‐alkanes (C₁₁H₂₄–C₁₅H₃₂) when statistical methods (cluster analysis and likelihood ratio approach) were applied.     

乙醇-氨法化学萃取精制直馏柴油研究

以兰州石化公司提供的直馏柴油为原料，考察了乙醇－氨法萃取精制直馏柴油的最佳实验室操作条件，并首次将聚结过滤法和溶剂部分循环再生法应用于醇－氨法萃取精制直馏柴油研究。试验结果表明，在评选的最佳实验室操作条件下采用聚结过滤法处理氨精制油，消除了溶剂损耗，溶剂回收率从89．26％提高到99．82％以上，采用溶剂部分循环再生方法，使溶剂再生负荷和再生能耗下降50％，克服了现有醇－氨法的缺点，精制柴油质量完全满足产品指标要求。     

B2O3对Ag/TiO2-Al2O3吸附剂的柴油吸附脱硫性能影响

采用浸渍法制备了不同B₂O₃负载量(e.g. 5%~20% (w))的Ag/TiO₂-B₂O₃-Al₂O₃吸附剂。以含硫量为245.36mg(S)/L 的商业柴油作为考察对象,常温常压下采用静态评价进行吸附脱硫性能研究。结果表明,B₂O₃改性后的Ag/TiO₂-Al₂O₃吸附剂的柴油吸附脱硫活性有了较大提高,当B₂O₃的负载量为15%时,吸附剂的吸附脱硫活性最高,2%Ag/4%TiO₂-15%B₂O₃-Al₂O₃ (w)的饱和吸附硫容达到2.36mg(S)/g 吸附剂。这对于未经预处理的商业柴油而言,吸附脱硫活性已经达到较高水平。采用N₂物理吸附、O₂化学吸附、X射线衍射(XRD)、NH₃程序升温脱附(NH₃-TPD)、傅里叶红外光谱(FT-IR spectra)、¹¹B核磁共振(¹¹B-NMR)等表征手段对不同负载量B₂O₃改性Ag/TiO₂-Al₂O₃吸附剂的织构性质、晶相结构和表面酸性的影响进行研究。关联活性测试和表征结果发现,吸附剂的吸附脱硫活性主要与吸附剂的表面弱酸性有关,而B₂O₃改性在吸附剂表面引入了较多的四配位的BO₄物种,能显著增加吸附剂表面弱酸性位点数量,提高吸附剂的吸附脱硫活性。     

Evaluation of a microwave-assisted extraction technique for determination of water-soluble inorganic species in urban airborne particulate matter

A simple and rapid microwave-assisted extraction (MAE) technique has been developed for the determination of water-soluble inorganic species (cations: Na⁺, NH₄⁺, K⁺, Ca²⁺ and Mg²⁺ and anions: F^–, Cl^–, NO₃^–, PO₄^3– and SO₄^2–) in airborne particulate matter. The analytes were extracted under different treatment conditions such as microwave power and extraction time. They were quantified using ion chromatography. The observed concentrations and recovery yields obtained under different conditions were compared. The results of a comparison between this MAE and sonication using NIST SRM 1648 are also given in this paper. The optimized MAE technique gave results in good agreement with the values obtained by the sonication. For some ions, for example Mg²⁺ and K⁺, recovery was low with both techniques. The results demonstrated that the optimized MAE is fast and efficient compared with conventional ultrasonic extraction. Urban airborne particles were collected and subjected to the MAE followed by the IC analysis to determine the relative proportions of different water-soluble inorganic species. These results are briefly discussed.     

满足欧Ⅲ排放标准的汽油车中偶催化剂

 制备了高性能稀土储氧材料Ce0.5Zr0.4Y0.1O2和镧稳定的氧化铝(La-Al2O3), 并以此为基础制备了中偶汽油车尾气净化催化剂. 经老化前后的性能检测证实,稀土储氧材料具有优异的织构性能和储氧性能且高温稳定性优良; La-Al2O3具有优异的织构性能及优异的抗高温老化性能. 中偶催化剂对HC, CO和NOx具有优异的低温活性、抗高温老化性能和低的劣化系数. 捷达-MT型汽油车排放检测表明该催化剂能够满足欧Ⅲ排放标准.     

负载型磷钨酸对柴油催化氧化脱硫

采用过量浸渍法和吸附法把磷钨酸(PW12)负载在TiO2、改性Y分子筛(GY)、AC载体上,并用负载后的催化剂对柴油(含硫量540 mg.L-1)进行催化氧化脱硫,结果表明,3种催化活性强弱顺序为:GY>TiO2>AC,且当GY上负载PW12的质量分数为30%的PW12/GY催化脱硫效果最好。对催化剂进行了酸强度测     

Fe-V/TiO_2催化剂NH_3选择性催化还原柴油车尾气NO_x

采用浸渍法制备了一系列不同Fe/V比例的Fe-V/TiO2催化剂,考察了催化剂在模拟柴油车尾气中催化还原NOx的催化性能,采用TG、XRD、H2-TPR、NH3-TPD和Raman光谱对催化剂进行了表征。结果表明,当Fe引入后,能显著降低V2O5在高温下的挥发,减轻了钒系催化剂在移动源的生物毒性危害。其中,Fe/V比为1∶1(Fe1-V1/TiO2)的催化剂形成了FeVO4活性中心,表现出最好的催化活性,在220~420℃NOx转化率可达到90%以上。此外,Fe1-V1/TiO2催化剂高温热稳定性较好,并且具有较强的抗硫性能。