Hydrogenation of heavy liquids from a direct coal liquefaction residue for improved oil yield

For hydrogenation of heavy liquids in direct coal liquefaction residue (DCLR) within the direct coal liquefaction (DCL) process, heavy liquids in a DCLR derived from a bench-scale Shenhua DCL process using Shenhua coal are evaluated under two conditions. One simulates the coal liquefaction conditions of the Shenhua plant in the presence of a Fe-based Shenhua catalyst; the other one simulates the online hydrotreating conditions in the presence of a NiMo/Al₂O₃ catalyst. The results show that the heavy liquids of DCLR can be hydrogenated under these two conditions yielding less heavy products; hydrogenating the heavy liquids under the online hydrotreating conditions is more effective than that under the coal liquefaction conditions; the preasphaltene fraction is a main problem that yields non-soluble materials under these hydrogenation conditions. The results suggest that hydrogenation of toluene soluble and tetrahydrofuran soluble fractions of the DCLR under the coal liquefaction and online hydrotreating conditions is feasible, but their conversion to lighter products are inapparent under the coal liquefaction conditions, and elimination of the formation of tetrahydrofuran insoluble fraction in the online hydrotreator should be considered.     

SOME OBSERVATIONS ON ELECTROOSMOTIC DEWATERING (EOD) UNDER A.C. ELECTRIC FIELD CONDITIONS

ABSTRACT

The electroosmotic dewatering (EOD) reported by Yoshida et al. (3) under low-frequency A.C. conditions is shown to be equivalent to EOD carried out under D.C. conditions with periodic polarity reversal. The interpretation of their results is carried out here in terms of electrochemical considerations (e.g., pH gradients, zeta potentials) with lesser role assigned to factors considered paramount by Yoshida, e.g., heating effect in the dry region near the anode.

More importantly, it is pointed out that the practical advantages of EOD under A.C. conditions claimed by Yoshida et al. are based on an invalid comparison of their results with EOD under continuous D.C. conditions; a comparison under equivalent conditions would be between low-frequency A.C. conditions and those under D.C. field but with periodic polarity reversal — the enhanced dewatering claimed under “A.C. conditions” by Yoshida would disappear when EOD under D.C. conditions with periodic interruption and/or polarity reversal is considered.     

Screening catalytic lipase activities with an analytical supercritical fluid extractor

Two different screenings of several commercial lipases were performed to find a lipase with superior performance for the conversion of lipid moieties to their fatty acid methyl ester (FAME) derivatives under supercritical conditions. The first screening was done under hydrolytic conditions in a buffer. The second screening was done under supercritical conditions with CO₂, utilizing some of the same lipases for the methanolysis of different lipids. For the substrates studied, there was a significant difference in lipase activity under the two above conditions. Significant hydrolytic activity was demonstrated for three different lipid types (triglycerides, sterols, and phospholipids) with Lipase PS30, but when the same lipase was immobilized on an Accurel carrier (polypropylene), the activity decreased considerably. The opposite was found for Lipase G, which showed strong activity when immobilized and under supercritical conditions. Furthermore, Chirozyme L-1 was superior under supercritical conditions. The altered substrate specificity that some of these lipases show in supercritical CO₂ suggests several interesting synthetic options and applications under these conditions.     

微波辐射法合成新型阳离子淀粉

研究了在基本干的反应条件下利用微波合成新型阳离子淀粉的方法,并通过实验确定出微波干法合成新型阳离子淀粉的最优反应条件为微波辐射强度选定为中低火档（40%）、微波照射时间为9 min、保温温度为60℃、保温时间为30 min,然后在优化后的反应条件下采用微波干法合成了不同理论取代度的新型阳离子淀粉。实验表明：微波干法与一般合成阳离子淀粉所用的湿法相比,具有反应效率高、反应时间短等优点。     

氯氢处理工序控制的难点和相应措施

结合氯氢处理工艺的特点，分析正常生产、异常状态下、事故状态下和变更后的生产过程控制中存在的主要难点，并提出相应的解决办法。     

435/50R19.5全钢载重子午线轮胎钢丝帘线受力分析

以435/50R19.5全钢载重子午线轮胎为例,采用有限元方法分析轮胎在充气、静负荷、侧倾、侧偏和驱动工况下带束层和胎体钢丝帘线的受力状况.结果表明,在充气和静负荷工况下,带束层和胎体钢丝帘线受力对称,在侧倾、侧偏及驱动工况下受力不对称;在各种工况下胎体钢丝帘线受力曲线形态差异较小,而带束层钢丝帘线差异较大.     

Effect of Atmospheric Humidity on the Fatigue Crack Propagation Behavior of Short Cracks in Silicon Nitride

The effect of the environment on crack-growth processes in silicon nitride was studied by investigating the static and fatigue crack-growth behavior of small surface cracks, as influenced by testing (i) in the ambient environment, (ii) in distilled water, (iii) under vacuum, and (iv) in toluene. A principal finding was that testing under cyclic conditions led to crack-growth rates that were much higher in air than in toluene, whereas testing under static conditions in air or toluene led to minor differences in the rate of static fatigue crack growth. This difference in sensitivity to the environment under static and cyclic loading conditions was attributed, in part, to a much-greater extent of microcracking at the surface ahead of the main crack in air under cyclic conditions, in comparison to that in other environments. This propensity for microcracking at the surface in air under cyclic conditions also was reflected in the aspect ratios of the crack shapes that developed.     

Primary fragmentation of limestone under oxy-firing conditions in a bubbling fluidized bed

Primary fragmentation of two limestones was studied in a lab-scale bubbling fluidized bed under simulated oxy-firing conditions and, for comparison, under traditional air-firing conditions. The influence of bed temperature, particle size and simultaneous occurrence of sulphation reaction was tested. Additional experiments in a heated strip apparatus were performed to determine if primary fragmentation occurred under high heating rate conditions, but in the absence of particle collisions.Results of the experiments show that only limited fragmentation occurred to both limestones tested under all operating conditions. Under oxy-firing conditions primary fragmentation was significantly reduced with respect to air-fired operation, most likely because of the absence of limestone calcination under high CO₂ atmospheres. Thermal shock upon limestone injection in the hot bed appears not to be able to induce significant particle fragmentation by its own.Particle size, bed temperature and simultaneous occurrence of sulphation reaction were found not to influence significantly the limestone primary fragmentation extent under both oxy-firing and air-firing conditions. On the contrary, the limestone type was found to be a more important variable with respect to the fragmentation tendency.     

Comparative study of quality characteristics of korean soy sauce made with soybeans germinated under dark and light conditions

This study was conducted to evaluate the effects of germinating soybeans under dark and light conditions on the quality characteristics of Korean soy sauce made with germinated soybeans. The germination rate of soybeans germinated under dark conditions (GSD) was higher than that of soybeans germinated under light conditions (GSL), whereas the lengths of sprouts and relative weights of GSL did not differ from those of GSD. The L, a, b, and ΔT values of GSL were significantly lower than GSD. The color of GSD remained yellow, while GSL changed to a green color due to photosynthesis by chlorophyll. The total amino acid contents in soy sauce fermented with soybeans germinated under dark conditions (SSGD) and soy sauce fermented with soybeans germinated under light conditions (SSGL) were lower than in soy sauce fermented with non-germinated soybeans (SNGS). The levels of isoflavone content in SSGD and SSGL were significantly increased compared to the SNGS. In conclusion, the germination of soybeans under dark and light conditions is not only an increasing organoleptic preference, but also has implications for the health benefits of Korean soy sauce.     

用室内磨耗试验机研究胎面胶的耐磨性和抗湿滑性

使用室内磨耗试验机LAT100研究含NR、SBR、BR及不同品种炭黑胎面胶的耐磨性和抗湿滑性。结果表明,在各种使用条件下,BR耐磨性最佳。其中在极苛刻条件下,SBR耐磨性略优于NR;在温和路面条件下,SBR耐磨性略低于NR。抗湿滑性大小顺序依次为SBR,NR,BR。在极苛刻路面条件下,轮胎胎面胶建议使用N220和N330系列炭黑;胎面胶采用炭黑N234和N375,其耐磨性基本相同。     

不同预处理条件制备粘胶基ACF的吸附性能研究

本文通过改变制备活性碳纤维（ＡＣＦ）的预处理条件（预处理剂种类、预处理浸渍时间预处理浸渍温度、预处理剂浸渍浓度）,随后在相同的碳化和活化条件下来制取粘胶基ＡＣＦ。利用石英弹簧称ＢＥＴ法测出不同预处理条件下制备产基ＡＣＦ各自比表面积,并通过不同样品对苯酚、亚四基兰和碘的吸附量的测定,对不同预处理条件所制备的粘胶基地初步的探讨。     

EFFECT OF HIGH VOIDAGE ON MASS TRANSFER COEFFICIENT IN A FLUIDIZED BED

Experiments were carried out to determine the gas-solid mass transfer coefficient for the air-naphthalene system under fast-fluidized conditions. The data were obtained under conditions of high voidage (as high as 98%) and high gas velocities (0·5 m/s-2·2 m/s). The results indicate that the correlation for the mass-transfer coefficient in a gas-solid fluidized bed under low voidage conditions established by previous investigators can be extended to the fast fluidization regime. Significantly lower mass transfer coefficients were, however, obtained under high voidage compared to low voidage conditions.     

Comparison of Oil Soluble Green Tea Extract with Common Antioxidantive Ingredients in Bulk Oil under Different Storage Conditions

The antioxidant capability of oil-soluble green tea extract (OSGT) in canola oil was compared to common synthetic and plant-derived ingredients with antioxidant function. Three storage conditions were included—22–25 °C ambient, 60 °C heated and air-purging at 22–25 °C. The oxidation process was monitored by electron spin resonance spectroscopy for free radicals, peroxide value for primary oxidative byproducts, proton nuclear magnetic resonance for the loss of oxidatively labile protons, aldehydes as secondary oxidative byproducts and antioxidants residues. Except for tocopherols, the use of antioxidant ingredients improved the stability of the oils under all conditions. However, the extent of improvement differed under different storages for the same ingredients. Evaluating antioxidant ingredients and interpretation of data when using accelerated conditions need caution. Antioxidant level change under different storage conditions provide new insights on the mechanism working of antioxidants in bulk oil. OSGT has comparable performance to TBHQ under ambient temperature conditions. In conclusion, evaluating antioxidant ingredients under accelerated conditions needs caution. Oil-soluble green tea extract has comparable antioxidative performance to TBHQ in bulk vegetable oil systems without affecting organoleptic properties of the oils under ambient temperature regardless of temperature or oxygen levels.     

Colour fastness to industrial laundering: an international inter‐laboratory trial of the proposed ISO 105‐C12 test procedure†

A new laboratory single‐wash test procedure that describes four test conditions, ISO 105‐C12, has been developed to assess the colour fastness of textiles under industrial laundry conditions. Following an international trial, the intra‐laboratory repeatability and the inter‐laboratory reproducibility of the test were found to be fully acceptable. The results obtained under two of the laboratory test conditions were compared with five washes in an industrial laundry under similar conditions and acceptable correlations were found.     

Elastic-Plastic Contact Damage in a Lead Lanthanum Zirconate Titanate

Spherical indenters were used to produce elastic-plastic contact damage in a lead lanthanum zirconate titanate (PLZT) under conditions of quasi-static and impact loading. The extent of radial cracking produced under both loading conditions showed good correlation with the response predicted by an earlier fracture mechanics analysis for quasi-static conditions. Calculated radial crack lengths corresponding to conditions of impact loading exhibited excellent agreement with experimentally measured values. The dynamic hardness of the PLZT was determined to be ∼ 1.5 times the quasi-static hardness. Differences in the radial crack lengths produced under the two loading conditions were attributed primarily to this difference in hardness response.     

助剂对透明聚氨酯弹性体耐黄变性能的影响

通过正交试验考察了在不同环境下不同的抗氧剂、紫外线吸收剂、助抗氧剂以及光稳定剂对透明聚氨酯弹性体耐黄变性能影响,优化了不同环境下的最佳助剂组成.结果表明:在室内避光条件下影响材料耐黄变性能的助剂主次顺序为助抗氧剂＞紫外线吸收剂＞光稳定剂＞抗氧剂;在室内日光灯照射条件下影响材料耐黄变性能的助剂主次顺序为紫外线吸收剂＞助抗...     

邻苯二甲酸二乙酯的合成

以邻苯二甲酸酐和无水乙醇为原料,对甲基苯磺酸为催化剂,环己烷为带水剂,在加热搅拌条件下回流8 h,合成邻苯二甲酸二乙酯。反应结束后,常压蒸馏除去乙醇。冷却后,经减压蒸馏得产品,产率为49.5%,产物经IR和折光率表征为目标产物。     

Shelf‐life prediction of edible fats and oils using Rancimat

Determining the shelf‐life of edible fats and oils under normal storage conditions is a tedious and time‐consuming task. Accelerated tests are therefore frequently used to determine the stability of the products at ambient conditions. However, the mechanisms of lipid oxidation at accelerated conditions may be different from those under normal storage conditions, leading to errors in the shelf‐life predictions. This article describes an automated accelerated method, namely Rancimat, for shelf‐life prediction of edible fats and oils under normal storage conditions, and the effect of its operational parameters on these predictions.     

Hydrogenation of canola oil as affected by chlorophyll

Chlorophyll was added to refined and bleached canola oil before hydrogenation, and the effects on hydrogena-tion rate, fatty acid composition and the percentagetrans isomers were determined. The hydrogenation rate was greatly slowed down by chlorophyll under selective (200 C and 48 kPa) and nonselective conditions (165 C and 303 kPa). Higher levels of chlorophyll reduced the reaction rate more than the lower levels under both conditions. Dropping points were slightly higher for the nonselectively hydrogenated samples than for the selectively hydrogenated ones. Addition of 1 mg/kg or more chlorophyll decreased the solid fat content under nonselective conditions. Addition of chlorophyll reduced thetrans isomer content under nonselective conditions. Nonselective conditions also resulted in a greater decrease of 18:3 and faster production of 18:0 than selective conditions at all levels of chlorophyll addition.     

臭氧处理分散染料生产废水的效率与机理研究

采用臭氧氧化处理分散染料实际生产废水,紫外-可见吸收光谱分析表明,碱性条件下芳香族有机物去除率约为酸性条件下的1.23倍,弱酸性条件下苯并异噻唑类有机物去除率为酸性条件下的1.05倍。碱性条件下废水的臭氧氧化以HO·氧化为主,其对特征指标UV254、UV350、UV435的去除速率分别为臭氧的22、7.5、180倍,同时实现有机物结构破坏和矿化。废水中的主要有机物为苯胺类和苯并异噻唑类,其助色基和生色基被氧化脱落,生成硝基苯、苯酚及有机酸等。