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木本油料是我国生物柴油产业未来原料生产和供应的特色和优势。本文以麻疯树为代表,从资源分布、麻疯果加工和油生产生物柴油技术等方面讨论了国内外研究和发展的现状,分析了我国麻疯树生物柴油产业发展存在问题,并提出了一些对策。 相似文献
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采用硫代硫酸铵器外预硫化制备CoMoS/γ-Al2O3催化剂,采用XRD、N2物理吸附、NH3-TPD、XRF等手段对催化剂进行表征,通过固定床微反装置研究其对麻疯树油加氢处理的性能。考察了硫化度、反应温度、氢气压力、反应时间对催化剂活性与催化产物分布的影响,并探讨了麻疯树油甘油三酯的反应路径。结果表明,硫化度为1的CoMoS1/γ-Al2O3催化剂活性最佳,在温度360℃、氢气压力3 MPa条件下,对麻疯树油转化率为96.3%,产物主要成分C15~18正构烷烃收率为75.6%,比相同条件下非硫化CoMo/γ-Al2O3催化剂的转化率提高36.9%。反应温度升至420℃时,CoMoS1/γ-Al2O3催化剂对麻疯树油转化率达100%,产物中无含氧物。麻疯树油加氢处理过程中,增大硫化度和反应温度、减小氢气压力有利于甘油三酯发生加氢脱羧、脱羰反应。 相似文献
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MoN/Zr-MCM新型催化剂的制备表征及其麻疯树油加氢脱氧的催化性能 《燃料化学学报》2018,46(11):1323-1331
采用水热法合成载体MCM-41与不同初始n(Si)/n(Zr)的Zr-MCM-41,由(NH_4)_6Mo_7O_(24)与载体经过共浸渍、高温焙烧、氨气程序升温氮化制备了Mo_2N/Zr-MCM-41新型加氢脱氧催化剂。采用XRD、BET、XPS、TEM以及吡啶红外等手段对催化剂进行了表征,并采用高压反应釜评价了不同n(Si)/n(Zr)的Mo_2N/Zr-MCM-41催化麻疯树油加氢脱氧反应的性能。结果表明,Zr改性后的载体与纯硅MCM-41同样具有良好的孔道结构,且L酸、B酸酸值提高。Mo_2N作为活性组分体现出了优异的加氢脱氧性能,在反应温度350℃、氢气分压3.0 MPa条件下催化的产品油组成主要为直链烷烃与芳香族化合物,占产品组分的90%(质量分数)以上;不同n(Si)/n(Zr)的新型催化剂脱氧率可高达100%;芳香族化合物含量高于直链烷烃,最高可占组成的72.09%(质量分数),主要以单环、双环芳香烃为主,碳链长度分布在C_(8-16);直链烷烃碳链长度分布在C_(8-17)。通过Mo_2N/Zr-MCM-41催化后的麻疯树油经分馏处理后可制备生物燃料。 相似文献
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《化学研究与应用》2015,(11)
以麻疯树果壳为原料,采用超声波辅助法提取麻疯树果壳中的多糖。在单因素实验的基础上,利用正交实验优化提取条件,并采用还原能力、DPPH·有机自由基的清除能力、羟自由基的清除能力作为麻疯树果壳多糖的体外抗氧化作用评价的3个指标。结果表明,超声波辅助提取麻疯树果壳多糖的最佳工艺条件为超声功率160 W,提取温度80℃,提取时间1.0 h,料液比1∶25(g·m L-1),在此条件下多糖得率为5.96%。抗氧化实验表明,麻疯树果壳多糖具有良好的还原能力,且清除·OH及DPPH·的能力与浓度呈正相关。当麻疯树果壳多糖浓度为0.5 mg·m L-1时,对·OH及DPPH·的清除率分别达到70%和60%。因此,该本方法操作简便、高效,测定快速。 相似文献
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麻疯油转酯化产物的高效液相色谱分析 总被引:2,自引:0,他引:2
建立了高效液相色谱法同时测定麻疯油转酯化产物中4种主要脂肪酸甲酯的分析方法。样品经膜处理后用丙酮溶解,采用Hypersil ODS(C18)色谱柱进行分离。以乙腈为流动相进行等度洗脱,内标法定量,同时对色谱条件进行优化。结果表明,在优化的色谱条件下4种脂肪酸甲酯在10 min内得到良好的分离,标准曲线的线性相关系数均达到0.999以上,平均回收率为96%~98%,重现性相对标准偏差为7.2%~10.2%,重复性相对标准偏差为0.31%~2.02%。与气相色谱法相比,该方法具有较高的灵敏度,可用于麻疯油转酯化产物中脂肪酸甲酯含量的测定,为麻疯油转酯化反应制备生物柴油的定性定量分析提供了参考依据。 相似文献
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利用手持技术改进测定乙醇分子结构实验 总被引:1,自引:0,他引:1
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1989,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988. 相似文献
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由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。 相似文献
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Mustafa R. Ibrahim Zacharia A. Fataftah Paul von Ragu Schleyer Peter D. Stout 《Journal of computational chemistry》1987,8(8):1131-1138
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases. 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1988,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae. 相似文献
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Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin
E. I. Kapinus V. A. Ganzha B. M. Dzhagarov E. I. Sagun V. B. Pavlenko 《Theoretical and Experimental Chemistry》1989,25(2):146-151
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989. 相似文献