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以碱土金属氧化物(MgO、CaO和BaO)作为裂解催化剂,在实验室自制的3 L裂解反应釜中对酸化油进行裂解脱氧制备烃类燃油。结果显示:3种碱土金属氧化物催化裂解酸化油所得液体燃油产率为70%~80%,特别是CaO和MgO作为裂解催化剂能够有效地脱氧,能够在较低的温度下获得更多的液体燃油,同时燃油的酸值低于20 mg/g。以硬脂酸钡、硬脂酸钙、硬脂酸镁为模型化合物研究废弃油脂裂解反应动力学,先进行热重分析,再利用分布活化能法对热重结果进行动力学参数计算,结果表明:硬脂酸钡、硬脂酸钙、硬脂酸镁的裂解活化能依次降低,分别为268,204和127 kJ/mol。以上结果表明:用MgO催化裂解酸化油能够在较低温度下收集更多的液体燃油,从而在较低温度下实现废弃油脂的裂解转化,有效降低反应能耗。 相似文献
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用热失重(TG)技术以及在线热裂解(Py)技术对杭白菊浸膏热裂解产物进行了研究。TG曲线显示主要失重区间在120~620℃,质量损失高达87%,选取了失重比较大的几个温度点(300、400、550、620℃)和800℃作为裂解温度,以气相色谱-质谱法(GC/MS)分析其在不同温度下的裂解产物,并对添加不同量杭白菊浸膏的中试卷烟进行了评吸。结果表明:300、400、550、620、800℃裂解温度下检测到的挥发性热裂解产物分别为20种、29种、28种、26种,21种;550℃下杭白菊裂解产物主要是醛类、酮类、酯类和呋喃类物质;550℃时开始出现有害物质,且有害物质的量随着温度的升高而提高;杭白菊浸膏能够显著改善卷烟抽吸品质,赋予卷烟一种特殊的自然风味。 相似文献
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皂脚废水是油脂工业环境污染的主要物质之一。本文介绍了几种典型和最新的皂脚废水处理工艺,旨在有效提高皂脚废水的处理和利用水平,减轻环境污染。 相似文献
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采用热重分析法(TG)和裂解气质联用法(PGC-MS)对3种典型的次磺酰胺类橡胶硫化促进剂的热裂解行为进行初步研究。结果表明:在选定的分析条件下,TG法和PGC-MS法分析结果有一定的一致性;TG分析中,促进剂NS的质量损失初始温度、质量损失最快温度和质量损失终止温度均最低,促进剂CZ其次,促进剂DZ最高,促进剂CZ质量损失速率最大;PGC-MS分析中3种促进剂均可以检测到其原分子,小分子胺为区分3种次磺酰胺类硫化促进剂的主要标志物。 相似文献
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孙靖先;庄志麟;郭忠成;周仕禄;张锋锋;曹建敏 《化工中间体》2025,(1):77-80
深入探究羧甲基纤维素(CMC)在不同加热温度条件下的热裂解产物释放特性,进而为优化其在加热卷烟工艺中的应用提供理论支撑,研究采用热裂解-气相色谱质谱联用技术(Py-GC/MS)对不同温度下的CMC热裂解产物进行了详细分析。结果表明:CMC从275℃开始发生裂解,300~350℃裂解反应较活跃;CMC主要裂解产物为含氧杂环、酮类和酸类,占裂解产物总量的3/4以上,275~300℃时,酸类占比较高,随后逐渐降低,酮类物质占比从275℃至400℃逐渐增加,含氧杂环类总量随温度升高呈先升高后下降趋势;裂解产物中羟基丙酮和醋酸释放量较高,其次为乙醛、丙酮、2,3-丁二酮、(S)-5-羟甲基二氢呋喃-2-酮、糠醛。研究不仅揭示了羧甲基纤维素在不同加热温度下的热裂解特性,还为深入理解CMC的热行为提供了重要参考,有助于提升加热卷烟产品的香气和风味品质。 相似文献
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建立一种用气相色谱-质谱联用(GC-MS)与超临界CO2萃取结合的方法分析米糠酸化油中的不皂化物(角鲨烯、甾醇和脂肪醇)。分别以角鲨烯、甾醇、十六醇标准品为外标物,用外标标准曲线法测定角鲨烯、甾醇、脂肪醇的含量。结果表明,米糠酸化油中含有角鲨烯的质量分数为0.11%,甾醇的质量分数为1.16%,脂肪醇的质量分数为2.21%。同时,用气相色谱法对油中脂肪酸进行测定,以油酸甲酯作为参比物,十二烷作为内标物,用内标法测得脂肪酸质量分数为75.0%。油中磷脂的质量分数的测定采用灰化法和甲醇-冰乙酸萃取法,测得磷脂的质量分数为0.33%。 相似文献
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Wang Shurong Liao Yanfen Liu Qian Luo Zhongyang Cen Kefa 《Frontiers of Chemical Engineering in China》2007,1(1):35-39
The analysis of microstructure and polymerization degree showed that acid wash altered the cellulose morphology and decreased
the polymerization degree significantly. A series of experiments were done to study the effect of acid wash on cellulose rapid
pyrolysis. Experimental results showed that under acid pretreatment, the yield of bio-oil decreased while the production of
gas and char increased. With an increase in acid concentration, this trend would be further enhanced. Sulphuric acid limited
the formation of bio-oil more effectively than hydrochloric acid and phosphoric acid. According to the GC-MS analysis of bio-oil,
high-concentration acid wash restrained the formation of levoglucosan by catalyzing dehydration process and cross linking
reaction.
Translated from Journal of Fuel Chemistry and Technology, 2006, 34(2): 179–183 [译自: 燃料化学学报] 相似文献
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《云南化工》2017,(7):31-35
研究苹果酸和柠檬酸热裂解产物对卷烟品质的影响。利用热裂解-气相色谱/质谱法模拟苹果酸和柠檬酸在卷烟燃吸过程中产物的变化,研究不同裂解温度(300℃,600℃,900℃)条件下苹果酸和柠檬酸的裂解产物和对卷烟品质的影响,并对机理进行了初步的探讨。在不同温度热裂解时,苹果酸的热裂解产物,主要是乙酸,丙烯酸和2,5-呋喃二酮,柠檬酸热裂解产物主要是丙酮和柠康酸酐。苹果酸和柠檬酸的热裂解产物都产生了大量的酸性物质。相比柠檬酸,苹果酸更利于改善吸味,平衡烟气,增加烟气浓度。根据苹果酸和柠檬酸裂解生成的主要产物,对裂解原理进行了探讨,认为苹果酸可能按照三种途径发生裂解,柠檬酸可能按照两种途径发生裂解。 相似文献
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Spruce wood residues were treated in a vacuum pyrolysis Process Development Unit with a throughput capacity of 28 kg/h. Two aqueous phase condensate samples with COD concentration varying between 190 and 255 g/L were produced and sequentially extracted with dichloromethane and ethylacetate solvents. The soluble organic matter was composed of acidic, phenolic, alcoholic and ketonic compounds. The insoluble fraction was sequentially distilled at 100 and 110°C under atmospheric pressure. Mainly water was recovered in the first distillate, while the second distillate contained 30.4% formic and acetic acids, 69.4% water and 0.2% residual organic compounds. The distillation residue was rich in oxygen and was essentially insoluble in any organic solvent. The two aqueous phase pyroligneous samples were treated in Bat-telle's Thermochemical Environmental Energy System (TEESr?), a registered service mark of Onsite*Ofsite, Inc. of Duarte, California, U.S.A. The results of the tests showed that similar results were obtained with either feedstock. In batch tests a COD reduction of 99% was achieved. The product gas composition was typically about 49% methane, 5% hydrogen, 1 % ethane and 45% carbon dioxide. Tests in a continuous stirred-tank reactor produced reproducible data which can be used for process scale-up. Catalyst lifetime was identified as needing further improvement. The preliminary results demonstrated the technical feasibility of the catalytic gasification process as a useful step in the recovery of energy from the secondary condensate stream and the cleanup of the by-product water from vacuum pyrolysis of wood. 相似文献
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PY/GC-MS法研究烟碱热裂解产物 总被引:1,自引:0,他引:1
用在线热裂解技术(PY)将烟碱于300、600、650、700、750、800和900℃裂解,用气质联用(GC-MS)对其裂解产物进行了定性和半定量分析,结果表明,烟碱可裂解为麦斯明、可替宁、二烯烟碱、吡啶、喹啉、异喹啉、苯和1,7-菲啰啉等20种物质。在600℃以下烟碱只有少量裂解,在800℃时烟碱完全裂解。在800℃和900℃裂解产物大致一样。根据主要的裂解产物和其相对峰面积百分比的变化,对烟碱的裂解机理进行了初步探讨,归纳为8条裂解途径。为烟碱在卷烟燃烧中的分解过程提供了参考。 相似文献
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Keith D. Morrison Jason S. Moore Keith R. Coffee Batikan Koroglu Alan K. Burnham John G. Reynolds 《Propellants, Explosives, Pyrotechnics》2024,49(2):e202300268
Understanding the molecular composition of high explosives during thermal decomposition is vital for predicting the sensitivity, safety, and performance of explosive materials. The thermal decomposition of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) has been linked to the formation of furazans through a series of dehydration reactions of the NO2 and NH2 groups on the phenyl ring, along with breakdown into small molecules (≤120 amu). Molecular identification of compounds formed in this transformation of the furazans to light gases has been lacking. To address this, we have applied a pseudo-confined sampling system in a cryo-focused pyrolysis gas chromatography-mass spectrometry (pyGC-MS) system to molecularly identify these intermediates. By design, sublimation of TATB, which has complicated MS analyses of thermal degradation, was significantly reduced and additional compounds were identified with potential structural information. In addition to the known furazan compounds, one of these compounds forms from the loss of oxygen from benzo-trifurazan (F3) and produces an open ring structure that may be the first step in the formation of lower molecular weight furazan breakdown products. The loss of a nitro group from benzo-monofurazan (F1) was also discovered and implicates the formation of oxidizing NO2 gas in the thermal decomposition mechanism. These findings are vital for understanding the proper heat flow from energetic materials on a molecular level, necessary when measuring enthalpy and developing decomposition models based on kinetic parameters. 相似文献