Composition of waxes from crude rice bran oil

Hard and soft waxes were separated from the tank settling of crude rice bran oil by solvent extraction and analyzed for their composition by gas liquid chromatography (GLC). The results showed that the melting points of the hard wax and the soft wax were 79.5 C and 74 C, respectively, and that the hard wax was mainly composed of saturated fatty alcohols of C24, C26 and C30, saturated fatty acids of C22, C24 and C26, andn-alkanes of C29 and C31. The soft wax was mainly composed of saturated fatty alcohols of C24 and C30, saturated fatty acids of C16 and C26, andn-alkanes of C21 and C29. In the soft wax, lauric acid was also detected.     

国内馏分油加氢裂化技术应用现状和发展趋势

通过对我国加氢裂化市场的发展历程、装置布局和技术供应等方面的介绍,阐明了我国加氢裂化市场的特点是装置规模趋于大型化,处理能力快速增长,装置总体布局不均衡,工艺流程以单段串联为主,尾油产品主要用作乙烯裂解原料等。面向未来,随着新燃油标准的出台,我国加氢裂化装置布局不均衡的局面将有所改善,市场需求对加氢裂化技术水平提出了更高的要求,市场竞争将日趋激烈。     

多产中间馏分油型中压加氢裂化催化剂的研制与性能评价

以改性Beta分子筛为酸性组分,W和Ni为活性金属组分,采用等体积浸渍法制备加氢裂化催化剂。采用XRD、BET、XRF、NH_3-TPD和Py-IR等对其进行物性表征,结果表明,加氢裂化催化剂具有孔分布比较集中、加氢金属组分分散均匀、强酸比例适中和L酸比例高等特点。对制备的加氢裂化催化剂在中压条件下进行活性与稳定性评价,结果表明,制备的加氢裂化催化剂具有活性和选择性高、稳定性好以及产品性质优异等特点,可长周期运转。     

FC-50中油型加氢裂化催化剂的反应性能及工业应用

介绍了以改性Y型分子筛为主要酸性组分、钨镍为加氢组分、采用浸渍法制备的FC-50中油型加氢裂化催化剂。催化剂具有较高的中油选择性和良好的稳定性,生产灵活性强,可在较大的转化深度范围操作。2010年6月,FC-50催化剂在中国石油化工股份有限公司镇海炼油化工股份有限公司1.2 Mt·a^-1加氢裂化装置上进行工业应用试验,工业标定结果表明,FC-50催化剂加氢性能好,目的产品选择性高,气体产率低,产品质量优,满足炼油厂的实际使用需求。     

Structure and properties of microcrystalline waxes

The structure of three series of microcrystalline waxes has been studied using X-ray diffraction and i.r. techniques. Their relative methylene/methyl group ratios as well as solid state parameters like size and shape of the unit cell, crystallite size and total crystalline fraction have been calculated. An attempt has been made to correlate these structural data with gross physical properties like oil content and needle penetration point. These correlations are found to hold good within any given series but varies from one series to another.     

Solubility of a diesel–biodiesel–ethanol blend,its fuel properties,and its emission characteristics from diesel engine

In this work, we studied the phase diagram of diesel–biodiesel–ethanol blends at different purities of ethanol and different temperatures. Fuel properties (such as density, heat of combustion, cetane number, flash point and pour point) of the selected blends and their emissions performance in a diesel engine were examined and compared to those of base diesel. It was found that the fuel properties were close to the standard limit for diesel fuel; however, the flash point of blends containing ethanol was quite different from that of conventional diesel. The high cetane value of biodiesel could compensate for the decrease of the cetane number of the blends caused by the presence of ethanol. The heating value of the blends containing lower than 10% ethanol was not significantly different from that of diesel. As for the emissions of the blends, it was found that CO and HC reduced significantly at high engine load, whereas NO_x increased, when compared to those of diesel. Taking these facts into account, a blend of 80% diesel, 15% biodiesel and 5% ethanol was the most suitable ratio for diesohol production because of the acceptable fuel properties (except flash point) and the reduction of emissions.     

活性剂FT对NR和BR及SBR胶料性能的影响

研究了橡胶活性剂ＦＴ与氧化锌不同并用比对ＮＲ,ＢＲ和ＳＢＲ胶料硫化特性和硫化胶物理性能的影响。试验结果表明,在ＮＲ和ＢＲ及ＳＢＲ胶料配方中活性剂ＦＴ可以等量替代４０％～６０％的氧化锌（即活性剂ＦＴ／氧化锌的最佳并用比为２．０／３．０～３．０／２．０）,而胶料的硫化特性基本保持不变,硫化胶物理性能稍有改善。     

Composition of insect waxes. I. Waxes of exotic coccidae:Gascardia madagascariensis,Coccus ceriferus andTachardia lacca

Composition of several coccid waxes has been determined by means of alumina and gas-liquid chromatography.Coccus ceriferus wax is a mixture of the esters of C₂₆ and C₂₈ alcohols with C₂₄, C₂₆ and C₂₈ acids.Tachardia lacca wax has a high percentage of free alcohols (essentially C₂₈ alcohol);Gascardia madagascariensis wax contains a large proportion of free acids. In addition to C₂₆, C₃₂ and C₃₄ normal chain acids, there are several C₃₀, C₃₂ and C₃₄ hydroxy acids, in which the hydroxyl function is situated in the middle of the hydrocarbon chain. Small proportions of odd and even hydrocarbons are present in all of the waxes investigated.     

Treatment of distillates and permeates from seawater desalination plants

Seawater desalination by evaporation or reverse osmosis processes is of rather great importance for potable water supply in countries without sufficient natural water sources. The distillate produced by evaporation as well as the permeate produced by reverse osmosis have to be treated to achieve satisfactory properties with respect to corrosiveness and health aspects.The paper discusses the composition and properties of distillate and permeates and the different remineralization and potabilization processes to make potable water and to avoid corrosion in the potable water system.     

Characterization and synthesis of waxes from homopterous insects

Wax (mp 102–103 °C) taken from the cochineal insectDactylopius confusus was saponified to give 11-oxotriacontanoic acid (1) and 15-oxotetratriacontanol (3) in good yields. The structure of these hydrolysis products follows most directly from examination of the mass spectra of the corresponding methyl ester (2) and acetate (4). These spectra are dominated by McLafferty rearrangements initiated by the ketonic carbonyl groups, and resulting in preferential loss of the unfunctionalized hydrocarbon end of the long-chain esters. The structures are confirmed by synthesis of both hydrolysis products via reaction of di-n-nonadecyl cadmium with the appropriate acid chlorides and of the C₆₄ wax ester (5) itself by acid-catalyzed condensation of these moieties. Mass spectral examination of the cochineal wax previously characterized as 15-oxotetratriacontanyl 13-oxodotriacontanoate on the basis of purely chemical evidence confirms the assignment, and the Wooly Alder AphidProciphilus tessalatus is now found to produce the same C₆₆ keto-ester.Paper No. 40 of the seriesDefense Mechanisms of Arthropods.     

Composition and technological properties of coals from Mongolian deposits

The main characteristics of the composition of coals from Mongolian deposits and their reactivity in thermal dissolution and coking processes were determined. The thermochemical conversion of coals into hydrocarbon products was studied. It was found that Tavantolgoi coal is characterized by high coking properties with the yield of carbon residue to 82.3%. The composition of semicoking tar was studied by chemical analysis and IR spectroscopy.     

Composition,processing, and properties of biphasic zirconia bioceramics: Relationship to competing strength and optical properties

A study is made of relationships between composition, processing, structure and properties of biphasic zirconia bioceramics. The focus is on zirconia compositions with different yttria dopant contents used in modern dental restorations, namely 3–5 mol% yttria stabilized zirconia (3YSZ, 4YSZ, and 5YSZ). Crystallographies and densities are surveyed, sintering conditions examined, and microstructures characterized. Strength and optical tests are conducted on each YSZ, and dependencies on sintering temperature, cubic content and grain size analyzed. Strength correlates with the amount of tetragonal zirconia (t-ZrO₂) crystals with large lattice distortions (tetragonality). YSZ translucency correlates with content of cubic zirconia (c-ZrO₂) and t-ZrO₂ with low levels of tetragonality. Consistent with literature reporting, the materials rank in decreasing order 3YSZ, 4YSZ to 5YSZ for strength but increasing order for translucency. However, for a given composition, the data suggest that the strengths of densely sintered 3YSZ and 4YSZ actually increase with translucency, although that of 5YSZ remains undiminished. These trends are in apparent contradiction to prevailing experience, and offer potential future processing routes to optimization of clinical materials.     

Deep hydrotreating of middle distillates from crude and shale oils

The potential scientific and technological solutions to the problems that appear as a result of shifting the hydrotreating of crude oil middle distillates and shale oils from the ‘normal’ to the ‘deep’ mode are considered on the basis of the reactivities and transformation routes of the least-reactive sulfur-, nitrogen-, and oxygen-containing compounds. The efficiency of selecting the optimal feedstock, increasing the process severity, improving the catalysts activity, and using alternative catalytic routes are compared, taking into account the specific issues related to deep hydrodesulfurization/hydrodenitrogenation/ hydrodeoxygenation, i.e., chemical aspects, kinetics and catalysts.     

Composition and properties of coals from the Yurty coal occurrence

Coals from the Yurty coal occurrence were studied. It was found that the samples were brown non-coking coals with low sulfur contents (to 1%) and high yields of volatile substances (V ^daf to 53.4%). The high heat value of coals Q _s ^daf was 20.6–27.7 MJ/kg. The humic acid content varied from 5.45 to 77.62%. The mineral matter mainly consisted of kaolinite, α-quartz, and microcline. The concentration of toxic elements did not reach hazardous values.     

Composition and properties of coals from some deposits in Mongolia

Nine coal samples from different deposits in Mongolia were studied with the use of a set of chemical and physicochemical methods of analysis (proximate and ultimate analyses, low-temperature extraction, the chemical analysis of ashes, thermogravimetric analysis, IR spectroscopy, and thermal dissolution) for evaluating their composition and chemical-engineering properties.     

Formation and emission characteristics of VOCs from a coal-fired power plant

On-site measurements of volatile organic compounds (VOCs) in different streams of flue gas were carried out on a real coal-fired power plant using sampling bags and SUMMA canisters to collect gas samples,filters to collect particle samples,Gas chromatography-flame ionization detector/mass spectrometry and gas chromatography-mass spectrometry was the offline analysis method.We found that the total mass concentration of the tested 102 VOC species at the outlet of wet flue gas desulfuration device was (13456 ± 47) μg·m-3,which contained aliphatic hydrocarbons (57.9％),aromatic hydrocarbons(26.8％),halogen-containing species (14.5％),and a small amount of oxygen-containing and nitrogen-containing species.The most abundant species were 1-hexene,n-hexane and 2-methylpentane.The top ten species in terms of mass fraction (with a total mass fraction of 75.3％) were mainly hydrocarbons with a carbon number of 6 or higher and halogenated hydrocarbons with a lower carbon number.The mass concentration of VOC species in the particle phase was significantly lower than that in the gas phase.The change of VOC mass concentrations along the air pollution control devices indicates that con-ventional pollutant control equipment had a limited effect on VOC reduction.Ozone formation potential calculations showed that aromatic hydrocarbons contributed the highest ozone formation (46.4％) due to their relatively high mass concentrations and MIR (maximum increment reactivity) values.     

生物质阴离子树脂的合成、表征及吸附性能

采用环氧氯丙烷、二乙烯三胺和三乙胺等对麦草秸秆进行化学改性,制备改性麦草秸秆阴离子交换树脂（改性麦秸树脂）,研究改性麦秸树脂的性能指标并重点考察其对水体中NO^-₃的吸附性能及效果。 研究结果表明,改性麦秸树脂引入了带正电荷的胺基基团,可以显著提高对NO^-₃的吸附性能;拉曼、红外光谱及zeta电位分析证明改性麦秸树脂对NO^-₃的吸附机理为离子交换;吸附过程符合Langmuir等温吸附模式;竞争吸附实验结果表明,改性麦秸树脂对不同阴离子的竞争吸附顺序为SO^2-₄>H₂PO^-₄>NO^-₃>NO^-₂,改性麦秸树脂对NO^-₃的最大吸附量为52.1 mg·g^-1,与商业树脂相当;柱吸附实验表明,改性麦秸树脂对NO^-₃的柱饱和吸附量为45.2 mg·g^-1,0.1 mol·L^-1的NaCl及HCl溶液均可有效再生改性麦秸树脂。     

Lipase-catalyzed synthesis of waxes from milk fat and oleyl alcohol

A screening of five lipases was carried out for the synthesis of wax esters from stoichiometric amounts of oleyl alcohol and milk fat in which long-chain fatty acid content (myristic acid, palmitic acid, stearic acid, and oleic acid) represents 70% of the total fatty acid fraction. The lipases from Alcaligenes sp. and Chromobacterium viscosum both allowed for the best ester synthesis (around 60%) within 2 and 48 h, respectively. Enzeco® Lipase Concentrate gave 30% ester yield within only 2 h. During the time period of 166 h, less than 20% ester synthesis was obtained with Lipozyme? 10,000L whereas Enzeco® Lipase XX did not catalyze the reaction. Owing to commercial availability, the food-grade Enzeco® Lipase Concentrate preparation was selected for further experiments with a view to improve wax synthesis. Wax yields were compared for three substrate molar ratios, i.e., 0.5:1, 1:1, and 1.5:1 (alcohol/fatty acid). For 0.5:1 and 1.5:1 substrate molar ratios, the addition of water increased ester yields while the effect of silica gel addition was shown to be minor. The best improvement was obtained at a substrate molar ratio of 1.5:1 with addition of water, leading to 59% wax ester synthesis.