植物油加氢制备高十六烷值柴油组分研究进展

介绍了植物油加氢制备柴油的主要化学反应、工艺方法以及该项技术的工业化状况,分析了植物油直接加氢、先加氢后异构、直接脱羧工艺以及植物油与矿物柴油掺炼工艺的特点,阐述了各工艺采用的催化剂类型、工艺条件以及产品属性。指出了该领域存在的问题和研究方向。     

Modern processing of rapeseed

The various processing steps for rapeseed into finished oil and meal products have been reviewed. Particular attention has been given to recent developments, such as the inclusion of an extruder step in oil extraction, an aqueous enzymatic process to separate flakes into oil, flour and molasses, the TOP total degumming process, and the new Centri-Ad process to eliminate small quantities of impurities (dissolved or emulsified) from large volumes of liquid by a continuous adsorption-centrifugation technique.     

Prediction of sulphur content in the industrial hydrotreatment process

The artificial neural network models were developed to determine sulphur content in the hydrotreatment product. Two models for two different types of feed were developed: light gas oil and vacuum gas oil. The developed ANN models use 6 input variables that are continuously measured in the process and are in accordance with the engineering knowledge and thermodynamics of hydrotreatment processes. Given models show good predictability of sulphur content in the hydrotreatment product and are, therefore, used in practice for continuous monitoring and optimization. This kind of application can be easily developed in any other hydrotreatment process with the available adequate historical data.     

Place of rapeseed in the edible oil market

The potential for rapeseed oil in the world edible oil market is evident in the statistics of net exports of the principal vegetable oilseeds from primary producing countries. The last complete year for which figures are available is 1970, and in that year soybeans accounted for some 52% and rapeseed only 7.5% in oil equivalent. Since soybeans have only ca. 50% of the oil content of rapeseed, they are bought mainly for their yield of high protein meal. Conversely, rapeseed is bought for its oil content and produces a meal that is not only lower in protein but up to this time has been less acceptable as an ingredient in animal feed formulations. Fortunately for rapeseed, these problems are being tackled diligently and should be overcome in the near future. When this point has been reached, rapeseed will be a much stronger competitor in world markets for protein meal. The trend in the use of rapeseed oil in the Canadian domestic market is an indicator of the potential in world markets. It is displacing other edible oils that have dominated the Canadian market in the past. In the 1971 calendar year, 35.6% or 160.5 million pounds, i.e., 73,000 metric tons, of vegetable oil used in the manufacture of margarine, shortening and salad oils was rapeseed oil. Rapeseed oil is competing keenly with soybean oil in the Canadian market and in the future should be able to greatly enlarge its share of world trade. One of six papers presented in the symposium “Rapeseed Marketing and Breeding,” AOCS Meeting, Ottawa, September 1972.     

STRONG沸腾床示范装置工业应用

随着原油重质化程度的不断加深,沸腾床渣油加氢技术成为了炼厂提高渣油附加值的重要手段。抚顺石油化工研究院开发的STRONG沸腾床渣油加氢成套技术无需使用传统沸腾床技术中的高温高压循环泵及配套设备,提高了反应体系的稳定性与反应器空间利用率,降低了投资。首套采用STRONG沸腾床技术的工业化装置累计平稳运行8000 h,540℃+单程转化率达到了78%以上。     

Catalytic processes for the production of hydrocarbon biofuels from oil and fatty raw materials: Contemporary approaches

The scientific and technical achievements made during the last 15 years in the deoxygenation processes for the production of hydrocarbon biofuels from oil and fatty raw materials are reviewed. The most advanced methods for the processing of triglycerides into hydrocarbons are associated with the use of pyrolysis, catalytic cracking, and hydrotreatment processes similar to those already used at petrochemical plants and oil refineries. The hydrotreatment technologies, which have already been adopted or ready for industrial application, are considered in more details. Nonsulphide catalysts for the single-stage production of waxy diesel fractions from vegetable oils and combined technologies are promising for reducing the consumption of hydrogen and increasing the yield of hydrocarbon products and the flexibility in obtaining different types of fuel.     

Determination of Origin of Commercial Flavored Rapeseed Oil by the Pattern of Volatile Compounds Obtained via GC–MS and Flash GC Electronic Nose

Flavored rapeseed oil (FRO) is a typical hot‐pressed oil and is widely consumed in China due to its strong characteristic flavor and intensive color. In this study, volatile profiles of 33 representative commercial rapeseed oils in China are characterized by gas chromatography‐mass spectrometry (GC‐MS) and flash gas chromatography (GC) electronic nose system. 51 volatile compounds are identified and the nitriles (methallyl cyanide and 5‐cyano‐1‐pentene), aldehydes (nonanal, 3‐furaldehyde, and 5‐methyl‐2‐furancarboxaldehyde), alcohols (1,5‐hexadien‐3‐ol, 2‐furanmethanol, and phenylethyl alcohol), and pyrazines (2,5‐dimethyl‐pyrazine and 2,6‐dimethyl‐pyrazine) are the major volatile compounds in FROs. Glucosinolate degradation products account for the highest proportion of these volatiles, which are found to have a positive correlation with the erucic acid content (R² = 0.796, p < 0.01). FRO from Sichuan province in the southwest of China can be characterized by the obvious distinctions in flash GC electronic nose combined with principal component analysis, which indicates that the flash GC electronic nose can be used as a promising method to identify the origins of FRO. Practical Applications: This work is helpful for expanding the knowledge of volatiles of commercial flavored rapeseed oil. The data can also serve as a basis for the quality assessment of hot‐pressed rapeseed oil. Meanwhile, the flash GC electronic nose combined with principal component analysis can be used as a promising method for the classification of flavor rapeseed oil production areas.     

Diffusion of asphaltene molecules through the pore structure of hydroconversion catalysts

When hydrotreatment of heavy cuts by heterogeneous catalysis is carried out in liquid phase, the molecules’ state of containment in the porous network is very high. Moreover, at that state of containment, the size of asphaltenes and resins, from various origins, can be the cause for the different hydrotreatment yields. Consequently, volume constraints are added to the kinetic and thermodynamic ones (adsorption equilibrium): a given species can penetrate in the solid only if the necessary volume is available within the network.Hindered diffusion and adsorption of asphaltene molecules inside hydrotreatment catalysts’ carriers were studied. The system's kinetics was investigated by visible absorption spectroscopy. Asphaltenes were prepared by n-heptane separation and solubilized in toluene at a known concentration and put in contact with a given amount of catalyst support. The evolution of the concentration in the asphaltene's solution was followed, as a function of time, by measuring the absorbance of a monochromatic visible radiation (750 nm) through the asphaltene suspension.A model based on the “Stefan–Maxwell” equations, that takes into account the volume constraints by the Fornasiero's formulation, which supposes that the molecules collide only by equivalent volume, was developed. The parameters estimation has been performed and discussed. The results show that the diffusional limitations are important in the catalyst used for heavy oil hydrotreatment and the asphaltene adsorption is very strong in this type of material.     

Conditioning of flaked rapeseed using the Exergy steam processor – a report from full scale test runs in a Swedish crushing plant

Using superheated pressurised steam for conditioning seeds and beans is very effective and can reduce the costs for cleaning and refining the oil. By using the Exergy system the time to achieve 120–140°C is only 10–30 s and all enzymes will be deactivated. After water‐degumming the oil will contain less than 10 ppm phosphorous. At appropriate processing conditions the proteins can be heat‐treated to produce rumen by‐pass (protected protein), which has significant added value on the feed market. The process and product development has been done together with a Swedish crushing company. They have used the Exergy for many years. Results on both oil and protein from treatment of flaked rapeseed are presented.     

Characterization and HDS activities of mixed Fe–Mo sulphides supported on alumina and carbon

Alumina and activated carbon-supported mixed sulphides (FeMoS) were prepared as hydrotreating catalysts. Previous work had shown bulk Fe–Mo mixed sulphides to be promising catalysts for hydrotreatment. Characterizations of the solids by NH₃-TPD proved to be a good technique to classify the solids according to their acidic strength. Thiophene hydrodesulphurization (HDS) and High vacuum gas oil (HVGO) hydrotreatment, performed at atmospheric pressure and high pressure respectively, were used as catalytic tests. Depending on the support, a more or less important synergetic effect is observed. The results are in agreement with a possible direct desulphurization process. The acidic strength plays an important role in determining the hydrogenolysis/hydrogenation ratio of the catalysts.     

Inhibiting HDS and HYD reactions with quinoline on Co(Ni)–PMo(W)/Al<Subscript>2</Subscript>O<Subscript>3</Subscript> catalysts: Effect of active phase composition on stability in the hydrotreatment of a model petroleum raw material

Со(Ni)–PMo(W)/Al₂O₃ catalysts are prepared using Keggin heteropoly acids H₃PMo(W)₁₂O₄₀ and cobalt (nickel) citrate. The physicochemical properties of the catalysts are studied via low-temperature nitrogen adsorption, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. Their catalytic properties are determined in the hydrotreatment of a model raw material containing dibenzothiophene, naphthalene, and different amounts of quinoline (up to 1000 ppm of nitrogen), and in the hydrotreatment of a straight-run diesel fraction and vacuum gas oil. The composition of Со(Ni)–PMo(W)/Al₂O₃ catalysts plays an important role in the hydrotreatment of a complex hydrocarbon raw material. Ni–PW/Al₂O₃ catalyst is more resistant to organonitrogen inhibitors than Ni(Co)–PMo/Al₂O₃ samples with more reactive active sites. Ni–PW/Al₂O₃ catalyst provides the greatest depth of conversion for sulfur- and nitrogen-containing compounds and polycyclic aromatic hydrocarbons in the hydrotreatment of vacuum gas oil.     

Conversion of vegetable oils under conditions of catalytic cracking

The effect of the composition of zeolite containing catalyst, the conditions of conducting the process, and the nature of oils on the distribution of target products during conversion under conditions of catalytic cracking is studied. The study is performed on bizeolite catalysts containing zeolites (ultrastable Y and ZSM-5 at different ratios) and on catalyst LUX containing18 wt % of zeolite Y in the HREY form. It is shown that the presence of zeolite ZSM-5 in the catalyst composition promotes the formation of olefines C₂–C₄. An increase in the severity of cracking process (elevated temperatures and catalyst: raw material ratios) improves the yield of gaseous products and coke with a simultaneous reduction in the yield of the gasoline fraction. The effect the nature of vegetable oils has is studied using the examples of palm, rapeseed, mustard, and sunflower oils. It is demonstrated that for the maximum yield of olefines C₂–C₄ and gasoline, we must use oils with elevated contents of saturated fatty acids. The regularities of the simultaneous cracking of sunflower oil and vacuum gas oil are studied. It is been found that upon simultaneous cracking, the total conversion of the mixed feedstock and yield of gasoline fraction increase; the maximum effect is attained with the addition of 3–10 wt % of vegetable oil.     

Catalytic Cracking of Rapeseed Oil with Binary Oxide Systems: An Alternative to Production of Petrochemicals

The aim of this work is to evaluate analytical tools for fast assessment of the catalysts’ ability to conduct a catalytic cracking process with the use of vegetable oils. The practical context of the presented concept relates to the use of cracking reaction products as valuable chemical raw materials. The proposed analytical tools allow for quick assessment of reaction products, indication of the molecular weight range, or the presence of specific functional groups. We want to emphasize that vegetable oils can not only be raw products for biofuels but also an alternative to petrochemicals. The study was undertaken to determine the influence of acid–base properties of catalysts on the rapeseed oil conversion process at 500°C. The effect of these properties on the character of the process and quality of the products obtained was shown to be very high. Basic correlations between the formation of coke, gaseous products and dehydrogenation products, and acid–base parameters of the individual catalysts have been observed. The use of spectroscopic methods (FTIR - Fourier Transform Infrared Spectroscopy, ¹H NMR - Nuclear Magnetic Resonance) for fast qualitative analysis of the products is described.     

Effects of processing on the functional properties of canola/rapeseed protein

Canola rapeseed is a major oilseed in Canada, Europe and Japan. Recently, Generally Recognized As Safe (GRAS) status was granted to low erucic acid rapeseed oil for use in the U.S. market. Commercial oil extraction of the seed results in a meal that contains 44% protein and which has been subjected to considerable heat. The meal is presently utilized as livestock feed supplement. A number of processes for the preparation of protein concentrates and isolates from canola/rapeseeds and meal have been proposed, although none have proven commercially viable. In addition to protein concentration, a successful process must reduce the levels of glucosinolates, phenolics, phytates and fiber. These antinutrients present a barrier to the use of canola/rapeseed protein materials in foods. Processes to produce protein concentrates have included water extraction of undesirable compounds from heat denatured, dehulled seed followed by solvent extraction for oil recovery and the isopropanol washing of dehulled, defatted flours. Isolates have been prepared by traditional alkaline extraction, and by acid or water extractions followed by isoelectric, heat or polyelectrolyte precipitation of the protein. Isolates have been chemically and enzymatically modified to improve fooduse properties. In this paper, the effects of various processing methods on the functional properties of solubility, color and flavor of canola protein products are reviewed. Presented at the 78th American Oil Chemists' Society Annual Meeting, May 17–21, 1987, New Orleans, LA.     

Diffusion extraction of rapeseed glucosinolates with ethanolic sodium hydroxide

Glucosinolates are readily diffused from whole rapeseed by repeated extractions with ethanolic sodium hydroxide. Four 2 hr extractions or six 1 hr extractions were most efficient for the diffusion of glucosinolates with minimum losses of other seed constituents. The ethanolic sodium hydroxide treatment inhibited myrosinase activity and lowered sulfur concentration in the oil. The oil from treated seed gave a higher hydrogenation number than the oil from untreated seed. The oil content of rapeseed was not substantially affected by the diffusion extraction process. Loss of diffused solids was ca. 15%, and loss of nitrogen did not exceed 10%. Most of the nitrogen diffused from the seed was nonprotein nitrogen. The principal disadvantages of the ethanolic sodium hydroxide procedure were reduced solubility of the rapeseed proteins and the higher fiber levels in the meals. The treated seed may be suitable, after partial dehulling or air classification, for the preparation of protein concentrates.     

Fatty Rapeseed Products for Dairy Cows

In the present investigation (3 experiments) the effects of fatty rapeseed products were studied on both straw-based and hay-based rations for lactating cows. Compared rapeseed products, used as ingredients of concentrate mixtures, were full-fat rapeseed (43% oil), partially defatted rapeseed expellercake (19% oil) and fully defatted rapeseed meal (2% oil). The rapeseed and rapeseed expellercake compared to the defatted rapeseed meal resulted in significantly higher yields of milk and 4% fat-corrected milk, when barley straw was the dominating roughage. In the hay-based diet the positive effects of added fat were not as much expressed. The iodine number of the milk fat increased about 4 units, when feeding the high-fat rations, i.e. the softness of the butter was improved. The results indicate that supplementation of straw with fatty rapeseed products will improve the possibility of a biologically and economically beneficial use of cereal straw in dairy cow rations.     

Literature review of toxicological properties of petroleum and coal-derived oil products

The recent development of synthetic liquid fuel products from coal has raised the question of their relative health hazard compared with natural petroleum products.A review of the literature of natural petroleum products and coal-derived synthetic liquid fuels shows some level of mutagenic activity for each. In general, the coal-derived petroleum substitutes tend to be more mutagenic and carcinogenic than the natural petroleum products. Increased hydrotreatment of the coal-derived oil reduces the mutagenicity to levels comparable to the natural petroleum products. The COED syncrude product consistently shows a lower level of mutagenicity and carcinogenicity than all of the other coal-derived products that appear in the literature.     

Identification of carbazoles and benzocarbazoles in a coker gas oil and influence of catalytic hydrotreatment on their distribution

Fractions highly enriched in pyrrole benzologues have been extracted from a coker gas oil before and after hydrotreatment under selected operating conditions. Carbazole, methyl- and dimethylcarbazoles and benzocarbazoles have been identified by means of g.c. coelutions with standards. The study of these compounds after catalytic hydrotreatment has shown that benzocarbazoles are more effectively removed than carbazoles in highly hydrogenating conditions (partial pressure of hydrogen, 10 MPa; temperature, 360 °C) whereas alkyl carbazoles and more particularly 1-methyl derivatives are more altered at a high temperature (380 °C, partial pressure of hydrogen, 5 MPa).     

Hydrotreatment of Cracked Light Gas Oil

Since worldwide conversion processes are used to upgrade heavy oil to distillates, the hydrotreatment of light gas oil (LGO) as a downstream process has been used more extensively. This fraction (LGO) is produced from thermal or catalytic cracking or hydrocracking processes. It contains high amounts of unsaturates, nitrogen, and sulfur compounds which cause instability while in storage due to gum formation. The use of LGO as a fuel oil for diesel engines plugs the filter and produces sulfur and nitrogen emissions. These sulfur and nitrogen compounds arise from the cracking of heavy cuts and are aromatic-type molecules which are difficult to hydrogenate. This cut also possesses a low cetane index (CI) which must be increased (by aromatic hydrogenation) because of its poor motor performance. Color and color stability are associated with a high bromine number (BN, unsaturated content), nitrogen, and aromatic content. In order to improve these properties, a deep hydrogenation is sometimes required.     

Hydrotreatment of Cracked Light Gas Oil

Since worldwide conversion processes are used to upgrade heavy oil to distillates, the hydrotreatment of light gas oil (LGO) as a downstream process has been used more extensively. This fraction (LGO) is produced from thermal or catalytic cracking or hydrocracking processes. It contains high amounts of unsaturates, nitrogen, and sulfur compounds which cause instability while in storage due to gum formation. The use of LGO as a fuel oil for diesel engines plugs the filter and produces sulfur and nitrogen emissions. These sulfur and nitrogen compounds arise from the cracking of heavy cuts and are aromatic-type molecules which are difficult to hydrogenate. This cut also possesses a low cetane index (CI) which must be increased (by aromatic hydrogenation) because of its poor motor performance. Color and color stability are associated with a high bromine number (BN, unsaturated content), nitrogen, and aromatic content. In order to improve these properties, a deep hydrogenation is sometimes required.