聚乙烯类废弃塑料延迟焦化方法制取燃料油的研究

通过对比废弃塑料（PE）和渣油的热重曲线（TG/DTG）,研究了两者的热解特性,论证了利用延迟焦化方法处理聚乙烯类废弃塑料的理论可行性;同时通过模拟延迟焦化实验,针对性地考察了废弃聚乙烯延迟焦化及废弃聚乙烯与渣油共延迟焦化的反应特性,采用模拟蒸馏方法分析了燃料油产物的成分组成,探讨了废弃聚乙烯延迟焦化方法制取燃料油的生产可行性。结果表明,PE的主要热解温区为350℃~480℃,渣油的为250℃~460℃,两者的热解特性有很大的相似性。PE热解的液体产物中汽油和柴油馏分达到62％,蜡油馏分为38％;PE热解的气相产物为小分子的烃类和氢气。PE与渣油共延迟焦化的液体产物中汽油馏分明显比渣油单独焦化的增加。     

污泥热解油中类汽油组分组成和燃料特性分析

采用蒸馏工艺对污泥热解油进行加工,得到较轻的类汽油组分,利用气质联用对此部分进行化学成分分析,发现类汽油组分是由碳原子个数为6～13有机物组成的复杂混合物,其中含有烷烃24.32%、烯烃36.33%、芳烃22.96%、N、O有机物16.39%.将类汽油组分的燃料性质与车用汽油标准进行对比,发现除难闻气味和硫含量较高外,...     

Sustainable Diesel from Pyrolysis of Unsaturated Fatty Acid Basic Soaps: The Effect of Temperature on Yield and Product Composition

The production of sustainable diesel without hydrogen addition remains a challenge for low-cost fuel production. In this work, the pyrolysis of unsaturated fatty acid (UFA) basic soaps was studied for the production sustainable diesel (bio-hydrocarbons). UFAs were obtained from palm fatty acids distillate (PFAD), which was purified by the fractional crystallization method. Metal hydroxides were used to make basic soap composed of a Ca, Mg, and Zn mixture with particular composition. The pyrolysis reactions were carried out in a batch reactor at atmospheric pressure and various temperatures from 375 to 475 °C. The liquid products were obtained with the best yield (58.35%) at 425 °C and yield of diesel fraction 53.4%. The fatty acids were not detected in the pyrolysis liquid product. The gas product consisted of carbon dioxide and methane. The liquid products were a mixture of hydrocarbon with carbon chains in the range of C₇ and C₂₀ containing n-alkane, alkene, and iso-alkane.     

自由落下床中生物质与煤共热解的协同效应对焦油组成的影响

利用溶剂萃取-柱层析方法,将自由落下床中豆秸与大雁褐煤共热解以及单种原料热解的液体产品分为沥青烯、酚类、脂肪烃类、芳香烃类和极性物等组分。结果表明,共热解的沥青烯产率为11.4%,低于根据煤和生物质单独热解的质量加权平均计算值19.0%,且芳香性增大;与计算值相比,低分子量的酚类、甲基苯酚、二甲基苯酚及其衍生物的含量提高了5%;而且长侧链的脂肪烃含量减少。共热解焦油的芳香类组分中十氢萘的质量分数是43.37%,但其在单一原料热解焦油中并没有被检测到。热解油分析结果表明,自由落下床生物质与煤快速共热解过程中存在协同效应,其主要原因是,发生氢解和加氢反应。煤与生物质共热解有利于产生低分子量的化合物,改善油品的质量。     

Real-time method for the identification and quantification of hydrocarbon pyrolysis products: Part I. Development and validation of the infra red technique

Due to large heat load encountered in high speed flight (over Mach 5), the regenerative cooling of the engine leads to the study of the endothermic pyrolysis of the onboard hydrocarbon fuel, which acts as a coolant. However the control and regulation of such a technology implies to have a correct knowledge of the endothermic pyrolysis of the onboard hydrocarbon fuel, which motivates the development of a quantitative measuring method adapted to in-flight applications. A Fourier transform infra red spectrometer is used and a specific method has been developed to identify and to quantify the major hydrocarbon products of the pyrolysis. The technique is validated and tested at the outlet of the experimental pyrolysis process which operates under steady-state conditions from 823 K to 1023 K and up to 60 bar. Two mass flow rates (0.05 g s⁻¹ and 0.1 g s⁻¹) are studied with titanium reactor to determine the limits of validity and to improve the method. Several synthetic and jet fuels have been tested (heptane, decane, dodecane and two kerosenes). The quantities of five light hydrocarbons (methane, ethane, ethylene, propane, propylene) are determined. The method, based on classical least square processing, is validated with respect to gas chromatograph (and mass spectrometer) analysis notably. A minimum molar fraction of 5 mol.% can be obtained and the accuracy is better than 2 mol.%.     

Catalytic performances of kaoline and silica alumina in the thermal degradation of polypropylene

Polypropylene was cracked thermally and catalytically in the presence of kaoline and silica alumina in a semi batch reactor in the temperature range 400℃～550℃ in order to obtain suitable liquid fuels.The dependencies between process temperatures,types of catalyst,feed compositions and product yields of the obtained fuel fractions were found.It was observed that up to 450℃ thermal cracking temperature,the major product of pyrolysis was liquid oil and the major product at other higher temperatures(475℃～550℃) ...     

Effects of the types of zeolites on catalytic upgrading of pyrolysis wax oil

Because zeolites play an important role in an upgrading catalyst for heavy hydrocarbons in industrial refinery processes, the effects of the zeolite type on the upgrading of pyrolysis wax oil are investigated in this study. Raw pyrolysis wax oil was obtained from the pyrolysis of municipal plastic wastes in a commercial rotary kiln pyrolysis plant (Dongmyong RPF Co.). The catalystic experiments are performed for the three different types of commercial zeolites with different physicochemical properties in a continuous fixed bed reactor at 450 °C for 1 h as a MAT(micro-activity test) method: HZSM-5 (pure), zeolite Y (HY; pure or including 20% clay) and mordenite (HM; including 20% clay or alumina) catalysts. The highest conversion of pyrolysis wax oil into light hydrocarbons such as gas products and gasoline-range hydrocarbons is obtained for the HZSM-5 catalyst among them, and the composition of liquid products is found to become in the main aromatic components due to a shape selectivity. For the case of zeolite Y(HY), medium activity and the highest fraction of branched hydrocarbons with a high octane number, as well as a high fraction of aromatic products are shown. However, the mordenite (HM) with one-dimensional pore structure shows the lowest conversion of pyrolysis wax oil into light hydrocarbons and a very high fraction of paraffin product in the liquid product like the characteristics of raw pyrolysis wax oil.     

The effects of magnesium and aluminium ions’ additions on the kinetics of titanium dioxide structural transformation

Catalytic fast pyrolysis analysis of miscanthus over HZSM-5, La/ZSM-5, and Ca/ZSM-5 was performed using pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS). The characteristics of the catalysts used in this study were analyzed using XRD, SEM, Pyridine IR, ICP, and N₂ adsorption. The catalytic performance of the three catalysts was evaluated in terms of deoxygenation. Py–GC/MS results show that with increasing temperature, pyrolysis vapor yield first increased and then decreased. This may be due to secondary cracking at higher temperatures, which produced more gas products. Moreover, hydrocarbon content increased with rising temperature. The optimum temperature was found to be 600 °C, which resulted in the greatest liquid yield. All three catalysts increased pyrolysis vapor yield by about 30 %. Moreover, the hydrocarbon content of miscanthus increased from 6 to 39 %, 46, and 44 %, respectively, when HZSM-5, La/ZSM-5, and Ca/ZSM-5 were applied. In conclusion, the three catalysts were effective for deoxygenation of pyrolysis vapor yield. Considering both economic and catalytic upgrading effect, Ca/ZSM-5 may be the best catalyst.     

Radical copolymerization of the C9 hydrocarbon fraction of liquid pyrolysis products with maleic anhydride

Radical copolymerization of the C₉ hydrocarbon fraction of liquid pyrolysis products with maleic anhydride was studied. The influence of reaction conditions on the copolymer yield, its molecular mass, and maleic anhydride content was elucidated. Hydrophilic products showing promise as modifying additives to paper stock, binding agents, dispersants, and compatibilizers were prepared.     

Hydrodesulfidation of the diesel fraction of pyrolytic fuel on polymetallic catalyst

Results are presented of a study of the liquid product formed in pyrolysis of automobile tires and fractions of this product. The diesel fraction of the pyrolytic liquid fuel was hydrodesulfided on a polymetallic catalyst. The results of the hydrodesulfidation in a flow-through laboratory installation in the temperature range 320–380°C at a hydrogen delivery rate of 6 L h^–1 are shown. The experiment was performed during 1 h with preliminary activation in a flow of hydrogen for 2 h and raw material delivery rate of 4–16 mL h^–1 on a polymetallic Al–Ni–V–Mo catalyst supported by γ-Al₂O₃. It was found that the degree of purification grows by 14% as the delivery rate is lowered from 16 to 8 mL h^–1, and by 27% upon its decrease to 4 mL h^–1. With temperature varied at the optimal raw material delivery rate of 4 mL h^–1, the degree of purification also changes: the minimum degree of purification is observed at 320°C. The degree of purification grows by 7% as the process temperature is raised by 20°, and by 28% upon its increase by 40°.     

粉粒流化床中松木生物质热解特性的研究

通过冷模实验考察了双颗粒流化床的流化特性。结果表明,在适宜的气速范围内,双颗粒流化床层内部可保持较好的流化状态。松木生物质在粉粒流化床反应器中的热解和催化热解实验结果表明,生物质热解时挥发分的释放存在一个最快的温度区域,生物质中约92%的挥发分在723 K时即可释放完全。773 K时,生物质热解产物中的无机气体(IOG)、低碳烃气体(HCG)和碳氢化合物液体(HCL)的收率之和只有3.1%。随着热解温度的升高,IOG、HCG和HCL的收率均逐渐增加,1 173 K时,其收率之和达到58.7%,且产物主要以CO为主。CoMo-B催化剂可有效促进生物质催化加氢热解产物的二次气相反应,在863 K下可得到6.3%,轻质芳烃化合物(苯、甲苯、二甲苯和萘)是1 173 K下非催化过程的两倍。     

玉米芯快速热解油特性研究

利用层析法对玉米芯快速热解油进行分析。结果表明,裂解温度对热解油产率及其族馏分构成的影响很大。通过气相色谱(GC)分析表明,脂肪族馏分碳数分布主要在C12~34,在烷烃碳数分布上,脂肪族馏分与柴油相当。并利用傅里叶红外光谱(FT-IR)、核磁共振氢谱(1H-NMR)分析了600℃下得到的热解油特征,表明玉米芯快速热解油作为燃料和高品位化学品原料来源具有潜在的发展前景。     

Scrap Tires Pyrolysis: Product Yields,Properties and Chemical Compositions of Pyrolytic Oil

This investigation involves an experimental study on the pyrolysis of scrap tires under different operating conditions such as feedstock size and pyrolysis temperature by highlighting the properties of the whole liquid products generated during each thermal degradation process. The complete conversion temperature for the pyrolysis of used tires was close to 500?550°C. The characteristics of liquid fraction were determined by elemental analysis, chromatographic and spectroscopic techniques and distillation data. All the obtained atomic ratios are around 1,4 which is significant that such pyrolytic liquids are a mixture of aliphatic and aromatic compounds derived from polymeric materials. Analysis of the pyrolytic oil (pyro-oil) by chromatographic analysis showed that it was a complex mixture of organic compounds C₅?C₂₆, aromatics and a large proportion of light hydrocarbons that can be used as liquid fuels. Furthermore, the comparison distillation data indicates that more than 40% of such pyrolytic oil fraction with the boiling point range between 180?360°C is specified for diesel. It is noted that the viscosity decreases obviously from 4.87 to 1.79 with the increase in temperature.     

微波裂解硬脂酸钠脱羧成烃机理研究

可再生烃类燃料相对于脂肪酸甲酯(生物柴油)有显著优势. 本研究以硬脂酸钠为研究对象, 采用微波裂解技术开展脂肪酸盐脱羧成烃机理的研究, 通过气质联用等手段对裂解产物进行分析, 研究结果表明微波能选择性作用于硬脂酸钠羧基端, 导致其在微波场中发生偶极转向极化和界面极化. 离子或极性分子的Lorentz 力按照电磁波作用的方式运动, 有助于碳负离子的形成, 有效推动了脱羧反应的进行; 添加于反应体系中的甘油具有很高的介电常数, 在微波场中形成“高热位点”, 降低了脱羧反应活化能并为硬脂酸钠脱羧起到了供氢体的作用. 液体产物中端烯烃和正构烷烃系列从C₈～C₂₀有规律的分布, 符合烃类裂解的规律. 研究结果证实了由脂肪酸盐在微波作用和甘油做为供氢体的条件下, 脱羧裂解生产优质替代性烃类燃料和绿色化学品的可行性.     

Utilization of α-olefins obtained by pyrolysis of waste high density polyethylene to synthesize α-olefin-succinic-anhydride based cold flow improvers

A new route of utilization of α-olefin rich hydrocarbon fractions obtained by waste polymer pyrolysis was investigated. α-olefin-succinic-anhydride intermediate-based pour point depressant additives for diesel fuel were synthesized, in which reactions needed α-olefins were obtained by pyrolysis of waste high-density polyethylene (HDPE). Fraction of α-olefins was produced by the de-polymerization of plastic waste in a tube reactor at 500℃ in the absence of catalysts and air. C17～22 range of mixtures of olefins and paraffins were separated for synthesis and then, these hydrocarbons were reacted with maleic-anhydride (MA) for formation of α-olefin-succinic-anhydride intermediates. The olefin-rich hydrocarbon fraction contained approximately 60% of olefins, including 90%～95% α-olefins. Other intermediates were produced in the same way by using commercial C20 α-olefin instead of C17～22 olefin mixture. The two different experimental intermediates with number average molecular weights of 1850g/mol and 1760g/mol were reacted with different alcohols: 1-butanol, 1-hexanol, 1-octanol, i-butanol, and c-hexanol to produce their ester derivatives. The synthesized ten experimental pour point depressants were added in different concentrations to conventional diesel fuel, which had no other additive content before. The structure and efficiency of experimental additives were followed by different standardized and non-standardized methods. Results showed that the experimental additives on the basis of the product of waste pyrolysis were able to decrease not only the pour but also the cloud point and cold filter plugging point (CFPP) of diesel fuel, whose effects could be observed even if the concentration of additives was low. Furthermore, all additives had anti-wear and anti-friction effects in diesel fuel.     

Peat semicoking and hydrocracking

This work deals with thermochemical conversion of peat into solvent-soluble oil and volatile gaseous products by using pyrolysis and catalytical hydrocracking methods. Distribution of liquid compounds between solubilized in water, benzene, and in acetone was determined and as a result the oil yield as total solubles was calculated. Chromatographic and FTIR-spectroscopic methods were used to characterize the composition of conversion products. Investigation of peat pyrolysis regularities in comparison with those of oil shale by using Rock-Eval analysis demonstrated essential differences between peat and oil shale as pyrolysis feedstock. As a result of hydrocracking the total oil yield was increased more than twice compared with that of semicoking, 29.8 and 13%, respectively. Hydrocracking and semicoking led to significant deoxygenation of oil and solid residual conversion products via oxygen removal as carbon dioxide and water. Hydroxyl-, carboxyl-, carbonyl- and other oxygen functionalities in peat initial matter being hydrocracked and modified, the oil was characterized by elevated hydrocarbon content and decreased that of polar oxygen compounds. As the oxygen content of the product decreases, the energy content significantly increases and peat oil, particularly its hydrophobic fractions, can be used for synthetic liquid fuel.     

Catalytic pyrolysis of HDPE in continuous mode over zeolite catalysts in a conical spouted bed reactor

A study has been carried out using HZSM-5, HY and Hβ zeolite-based catalysts in the pyrolysis of high density polyethylene (HDPE) continuously fed into a conical spouted bed reactor (CSBR) at 500 °C and atmospheric pressure, with the aim being to assess the yields and composition of the main products (both light olefins and automotive fuel hydrocarbons). Product streams have been grouped into seven lumps: light olefins (C₂–C₄) and light alkanes (<C₄) in the gas fraction, the liquid fraction consisting of three lumps (non-aromatic C₅–C₁₁ compounds, single-ring aromatics and C₁₁₊ hydrocarbons), wax and coke. The results are compared with those already obtained in thermal pyrolysis in a CSBR and with those obtained in the literature using catalysts in bubbling fluidized beds. HZSM-5 zeolite-based catalyst is very selective to light olefins, ≈58 wt% once equilibrated; whereas high yields of non-aromatic C₅–C₁₁ products (around 45 wt%) are obtained with Hβ and HY zeolite-based catalysts. Wax yield increases as reactions proceed, especially with HY and Hβ zeolite-based catalysts, due to catalyst deactivation by coke formation. Product distribution with the different catalysts and their evolution throughout continuous operation by feeding HDPE is explained according to the different properties of the zeolites used.     

Production of High-Density Jet and Diesel Fuels by Hydrogenation of Highly Aromatic Fractions

Physicochemical characteristics and hydrocarbon composition of highly aromatic wastes (light gas oil from catalytic cracking, pyrolysis tar, coal tar, coal gasification tar) as a feedstock for producing high-density jet fuels are considered. The hydrogenation reactions of polycyclic aromatic hydrocarbons, including mixtures of hydrocarbons with different numbers of rings, are described. Catalysts for hydrogenation of highly aromatic waste to obtain fuel fractions are considered. Particular attention is paid to catalyst deactivation in the course of processing of this feedstock. A separate section deals with the choice and implementation of procedures for processing highly aromatic feedstock to obtain jet and diesel fuels.     

Pyrolysis oil from fast pyrolysis of maize stalk

Maize stalk was fast pyrolysed at temperatures between 420 °C and 580 °C in a fluidized-bed, and the main product of pyrolysis oil was obtained. The experimental results showed that the highest pyrolysis oil yield of 66 wt.% was obtained at 500 °C for maize stalk. Chemical composition of the pyrolysis oil acquired was analyzed by GC–MS and its heat value, stability, miscibility and corrosion characteristics were determined. These results showed that the pyrolysis oil could be directly used as a fuel oil for combustion in a boiler or a furnace without any upgrading. Alternatively, the fuel could be refined to be used by vehicles.     

Pyrolysis of waste tyres: The influence of USY catalyst/tyre ratio on products

In this paper, an ultrastable Y-type (USY) zeolite was investigated with two-staged pyrolysis–catalysis of waste tyres. Waste tyres were pyrolysed in a fixed bed reactor and the evolved pyrolysis gases were passed through a secondary catalytic reactor. The main objective of this paper was to obtain high concentration of certain aromatic hydrocarbons suitable to be used as a chemical feedstock rather than a liquid fuel, and the influence of catalyst/tyre ratio on the product yield and composition of derived oils. The light fraction (boiling point < 220 °C) was distilled from the derived oil prior to be analyzed with gas chromatography/mass spectrometry (GC/MS). It showed that the increase of catalyst/tyre ratio resulted in high yield of gas at the expense of the oil yield. The high catalyst/tyre ratio favored to increase the concentration of light fraction (<220 °C) in oil. Increasing the catalyst/tyre ratio resulted in significant changed in the concentration of benzene, toluene, xylenes and the alkyl aromatic compounds. For benzene and toluene, the highest concentration was obtained at the catalyst/tyre ratio of 0.5. The concentration of xylenes increased with the increasing of catalyst/tyre ratio.