A Technological Perspective for Catalytic Processes Based on Synthesis Gas

Abstract

Continuously increasing oil prices, a dwindling supply of indigenous petroleum, and the existence of extensive coal reserves has made the conversion of coal to chemicals and clean-burning fuels an increasingly important part of the national energy programs for a number of industrial nations. In particular, there is a growing interest in the production and use of synthesis gas as a feedstock for the manufacture of fuels and chemicals. Most of the proposed routes are catalytic in nature, and are directed at overcoming the limitations of Fischer-Tropsch chemistry, especially selectivity. Over the past several years, research efforts have led to new selective routes to various fuel fractions; to petrochemical feedstocks including light olefins and various aromatics; to commodity chemicals such as ethylene glycol, ethanol, and acetic acid; and to a number of other fuels and chemicals.     

高效、清洁、高附加值原则指导下适度、有序发展煤化工产业

针对我国可持续发展面临的能源瓶颈,指出适度、有序发展煤化工产业是我国现有能源结构环境下的必然选择。在低碳理念指导下,提出了煤炭资源的分质利用原则、高能效利用原则、综合利用原则、因地制宜利用原则和高附加值利用原则,比较分析了煤的各种化学转化途径,阐述了含氧醇醚材料替代石油路线、煤制芳烃、煤/天然气/煤层气制备乙炔等具有前景的清洁、高效转化过程,期望为煤化工产业的健康、有序发展提供科学思路。     

煤直接转化制高品质液体燃料和化学品

介绍了国家重点研发计划项目“低变质煤直接转化制高品质液体燃料和化学品的基础研究”的背景、研究现状以及研究任务与目标。研究工作可望在深入认识低变质煤中矿物特性和弱键合结构以及分子水平反应规律、直接转化过程反应途径、产物调控机制及定向催化转化原理;构建高品质和高产率油气的煤热解新反应器、煤加氢液化富产芳烃新工艺、高性能喷气燃料及化学品制备的高效催化剂以及新技术等方面取得突破,从而完善低变质煤直接转化制取高品质液体燃料及化学品的工艺技术体系。     

Chemical Coal Cleaning Assessments at Gulf

Abstract

Extensive work has been conducted at Gulf Research & Development Company over the past 5 years to assess the feasibility of commercializing chemical coal cleaning technologies. Elements of this work are reviewed in this paper. It is concluded that the use of chemical cleaning will await the development of markets for premium coals and the start of new market-oriented strategies by coal companies. The trend by electric utilities toward the use of more efficient fuels and the need to pay out high cost coal reserves may force coal companies to develop premium fuels for improving market share. Significant use of chemical methods in coal preparation is a distinct possibility in the future because of developments now under way in the use of coal as an alternative hydrocarbon feedstock in chemicals and fuels applications. The potential for chemical preparation of low-ash and low-sulfur coal for these new applications is discussed.     

Reactions of synthesis gas

The use of synthesis gas (syngas) offers the opportunity to furnish a broad range of environmentally clean fuels and chemicals. There has been steady growth in the traditional uses of syngas. Almost all hydrogen gas is manufactured from syngas and there has been a tremendous spurt in the demand for this basic chemical; indeed, the chief use of syngas is in the manufacture of hydrogen for a growing number of purposes. Methanol not only remains the second largest consumer of syngas but has shown remarkable growth as part of the methyl ethers used as octane enhancers in automotive fuels. The Fischer-Tropsch synthesis remains the third largest consumer of syngas, mostly for transportation fuels but also as a growing feedstock source for the manufacture of chemicals, including polymers. Future growth in Fischer-Tropsch synthesis may take place outside the continental United States. The hydroformylation of olefins (the oxo reaction), a completely chemical use of syngas, is the fourth largest use of carbon monoxide and hydrogen mixtures; research and industrial application in this field continue to grow steadily. A direct application of syngas as fuel (and eventually also for chemicals) that promises to increase is its use for Integrated Gasification Combined Cycle (IGCC) units for the generation of electricity (and also chemicals) from coal, petroleum coke or heavy residuals. In the period 2005–2015, the amount of syngas employed in this manner may approach that used for all other specific purposes. Syngas is the principal source of carbon monoxide, which is used in an expanding list of so-called carbonylation reactions.     

Liquid Fuels from Alternative Carbon Sources Minimizing Carbon Dioxide Emissions

The energy needs of the world continue to grow, as does the resulting environmental impact. Policy makers continue to call for alternative energies to replace today's petroleum‐based liquid fuels. However, liquid fuels have significant advantages, and it is probably unwise to abandon the existing infrastructure without appropriately exploring alternatives to lessen the environmental burden of producing liquid fuels. Biomass and coal are often proposed as alternatives to petroleum‐based carbon sources, but those processes lose a significant amount of their potential product to unwanted carbon dioxide emissions. However, combining biomass and coal with cleaner natural gas yields processes with less environmental impact to produce liquid fuels with small, zero, or even negative carbon dioxide emissions. Our process synthesis approach is applied to commonly encountered liquid fuel production methods to identify promising routes and to establish feasibility limits on those less promising alternatives. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2062–2078, 2013     

煤间接液化技术及其发展状况

介绍了煤间接液化技术的特点,从其原理、工艺路线、关键技术及发展现状等方面对间接液化技术进行了详细的阐述,指出发展煤间接液化是解决我国油品短缺的根本途径。     

The comparison study on the operating condition of gasification power plant with various feedstocks

Gasification technology, which converts fossil fuels into either combustible gas or synthesis gas (syngas) for subsequent utilization, offers the potential of both clean power and chemicals. Especially, IGCC is recognized as next power generation technology which can replace conventional coal power plants in the near future. It produces not only power but also chemical energy sources such as H₂, DME and other chemicals with simultaneous reduction of CO₂. This study is focused on the determination of operating conditions for a 300 MW scale IGCC plant with various feedstocks through ASPEN plus simulator. The input materials of gasification are chosen as 4 representative cases of pulverized dry coal (Illinois#6), coal water slurry, bunker-C and naphtha. The gasifier model reflects on the reactivity among the components of syngas in the gasification process through the comparison of syngas composition from a real gasifier. For evaluating the performance of a gasification plant from developed models, simulation results were compared with a real commercial plant through approximation of relative error between real operating data and simulation results. The results were then checked for operating characteristics of each unit process such as gasification, ash removal, acid gas (CO₂, H₂S) removal and power islands. To evaluate the performance of the developed model, evaluated parameters are chosen as cold gas efficiency and carbon conversion for the gasifier, power output and efficiency of combined cycle. According to simulation results, pulverized dry coal which has 40.93% of plant net efficiency has relatively superiority over the other cases such as 33.45% of coal water slurry, 35.43% of bunker-C and 30.81% of naphtha for generating power in the range of equivalent 300 MW.     

Brief Review of Precipitated Iron-Based Catalysts for Low-Temperature Fischer–Tropsch Synthesis

Topics in Catalysis - Fischer–Tropsch synthesis (FTS) is a promising way to produce clean liquid fuels and high value-added chemicals from low-value carbon-containing resources such as coal,...     

Integrated chemo- and biocatalytic processes: a new fashion toward renewable chemicals production from lignocellulosic biomass

Concerns over climate change and environmental pollution resulting from petroleum refining has spurred the exploitation of green replacements for producing chemicals and fuels. Valorization of lignocellulosic biomass into chemicals represents a promising alternative to petroleum refining. Biological and chemical catalysis are two leading routes for lignocellulose variolization, but strategies relying simply on biological or chemical conversion have shown limitations. Integrating biocatalysts with chemocatalysts could leverage the inherent strengths of both while circumventing their respective disadvantages, benefiting product yield and selectivity, and reducing cost and waste generation. This review focuses on the coupled chemocatalytic and biocatalytic synthesis of renewable chemicals from polysaccharides and their derived platform chemicals. In addition, strategies for producing value-added products from lignin via integrated chemical depolymerization and biological conversion are highlighted. The techno-economics of integrating chemocatalysts and biocatalysts in producing chemicals in the context of biorefinery are also discussed. Finally, perspectives on designing integrated chemical and biological catalysis for renewable chemicals production are provided. © 2022 Society of Chemical Industry (SCI).     

The fate of main gaseous and nitrogen species during fast heating rate devolatilization of coal and secondary fuels using a heated wire mesh reactor

Fast devolatilization experiments of coal and biomass fuels have been carried out using a heated wire mesh setup integrated within an FTIR spectrophotometer for in-situ gas analysis. A bituminous coal and slaughter/poultry biomass residues, currently utilized in the Dutch power sector as secondary fuels in coal-fired utilities, have been studied. The influence of peak temperature (500–1300 °C), heating rate (600–1000 K/s) and hold time at peak temperature on the devolatilization has been investigated. Particular emphasis was given to characterize the fuel-bound nitrogen partitioning of these fuels as a function of the various operating parameters. The results suggest that, for combustion applications, the effectiveness of primary measures for NO_x control can be enhanced when biomass fuels are co-fired with coal if a complete devolatilization is ensured in the fuel-rich zone of the furnace.     

实现我国煤化工、煤制油产业健康发展的若干思考

针对我国目前出现的盲目发展煤化工、煤制油的状况提出了实现我国煤化工、煤制油产业科学发展的建议。一是发展煤化工、煤制油必须坚持“适度、有序”原则;二是综合考虑社会投入,发展煤基车用替代燃料应定位在煤制油上,不宜发展“醇醚燃料”;三是发展煤化工、煤制油要高度关注国际原油和石化产品市场,认真分析产品的市场竞争力;四是发展煤化工、煤制油要积极推动煤炭生产企业与石油化工企业的以资本为纽带的强强联合。     

Process and Catalyst Needs for Hydrodenitrogenation

During the last decade there has been increased interest in the production of synthetic fuels and chemicals feedstocks from coal and oil shale due to declining petroleum reserves. Table 1 gives the projected gasoline to mid-distillate ratio through the year 2000 and beyond; the shift is away from high-octane fuels requiring a relatively high aromatics content and a relatively low hydrogen content to highly paraffin-based fuels having a high hydrogen content. Figure 1 shows the projected United States energy supply and demand through the year 1990 [2], Current petroleum production in the contiguous United States is about 9 million bbl/day and has declined at a rate of about 0.5 million bbl/day per year for a number of years. Alaskan oil will arrest this decline in production briefly but will not make up for even the loss in the rate of petroleum production incurred in the contiguous 48 states during the last 5 years. In all probability, declining production from current oil fields will not be offset by further new discoveries, and thus the United States will become increasingly dependent on foreign oil. Further, petroleum feedstocks are becoming harder to process as crude quality decreases, and as it becomes more and more necessary to process the bottom of the barrel. Declining oil supply in the face of increasing demand will ultimately require that some of the projected gap be made up with synthetics made from coal and oil shale. Such synthetic feedstocks and heavier petroleum fractions contain higher concentrations of nitrogen than light petroleum stocks, are decidedly more difficult to process, and will place increasing demands on hydroprocessing catalysts and processes.     

Recent advances on the reduction of CO2 to important C2 + oxygenated chemicals and fuels

The chemical utilization of CO₂ is a crucial step for the recycling of carbon resource. In recent years, the study on the conversion of CO₂ into a wide variety of C_2 + important chemicals and fuels has received considerable attention as an emerging technology. Since CO₂ is thermodynamically stable and kinetically inert, the effective activation of CO₂ molecule for the selective transformation to target products still remains a challenge. The well-designed CO₂ reduction route and efficient catalyst system has imposed the feasibility of CO₂ conversion into C_2 + chemicals and fuels. In this paper, we have reviewed the recent advances on chemical conversion of CO₂ into C_2 + chemicals and fuels with wide practical applications, including important alcohols, acetic acid, dimethyl ether, olefins and gasoline. In particular, the synthetic routes for CC coupling and carbon chain growth, multifunctional catalyst design and reaction mechanisms are exclusively emphasized.     

Process and Catalyst Needs for Hydrodenitrogenation

During the last decade there has been increased interest in the production of synthetic fuels and chemicals feedstocks from coal and oil shale due to declining petroleum reserves. Table 1 gives the projected gasoline to mid-distillate ratio through the year 2000 and beyond; the shift is away from high-octane fuels requiring a relatively high aromatics content and a relatively low hydrogen content to highly paraffin-based fuels having a high hydrogen content. Figure 1 shows the projected United States energy supply and demand through the year 1990 [2], Current petroleum production in the contiguous United States is about 9 million bbl/day and has declined at a rate of about 0.5 million bbl/day per year for a number of years. Alaskan oil will arrest this decline in production briefly but will not make up for even the loss in the rate of petroleum production incurred in the contiguous 48 states during the last 5 years. In all probability, declining production from current oil fields will not be offset by further new discoveries, and thus the United States will become increasingly dependent on foreign oil. Further, petroleum feedstocks are becoming harder to process as crude quality decreases, and as it becomes more and more necessary to process the bottom of the barrel. Declining oil supply in the face of increasing demand will ultimately require that some of the projected gap be made up with synthetics made from coal and oil shale. Such synthetic feedstocks and heavier petroleum fractions contain higher concentrations of nitrogen than light petroleum stocks, are decidedly more difficult to process, and will place increasing demands on hydroprocessing catalysts and processes.     

煤间接液化技术及其研究进展

介绍了煤经合成气间接液化合成液体燃料的原理及典型工艺。综述了煤间接液化技术的发展历程及其最新进展,讨论了国内外煤间接液化技术的工艺流程,重点介绍了煤间接液化过程中的核心问题,主要包括气化炉、费托合成反应器和费托合成催化剂,分析了煤间接液化的技术经济性以及对煤间接液化的工业应用前景进行了展望。分析表明：具有我国自主知识产权的煤间接液化技术建设100万吨级以上工业化装置在技术上可靠、经济上可行,且100万吨级工业化项目的成功实施将带动我国煤间接液化技术的产业化进程,加快形成具有中国特色的能源转化技术和产业。     

煤热解制焦油的工艺研究进展

煤热解是一种重要的煤炭分质利用技术,中低温热解焦油是制取液体燃料和化学品的重要原料。本文从对煤进行预处理、改变热解气氛、催化热解与催化加氢热解、煤与其它物质共热解、新型耦合热解工艺等方面综述了煤热解制焦油的工艺研究进展,探讨了影响煤热解过程焦油产率的因素及机理,并对各工艺进行了评价。     

Effect of Sulfur on the Fischer-Tropsch Synthesis

One of the principalcauses of present concern is the current unavailability of alternative sources of fuels for transporation. Other fuel imensive sectors, such as electric power generation, can depend on coal or nuclear fuel to provide the energy if petroleum-based fuels become scare. The transporation sector, on the other hand, is projected to need liquid fuels. Due to the relevant abundance of coal in the United States, it isimperative to find ways of converting coal to liquid fuels. Products from coal liquefaction processes contain a high aromatic content. Though this is a desirable comporent isgasoline, it is a very undersirable one in jet and diesel fuels (Table 1). In even higher boiling materials such as gas oils, the high aromatic content makes it quite difficult to produce gasoline by normal rednery processess. Fischer-Tropsch (FT)synthesis, in which carbon produces mainly straight chain aliphatic hydrogen obtained from coal gastfication are reacted over a caralyst, is the only develped coal-derived process which produces mainly straight chain aliphatic hydrocarbons. Although such aliphatic hydrocarbons are not very desirable on motor gasolines due to their low octare number, diesel and jet fuels containing such aliphatic, hydrocarbons are considered high quality materials. In addition, the higher boiling gas oil traction from the FT process is easily converted to gasoline and diesel fuel by conventional refining technology     

煤间接液化技术开发现状及工业前景

评述了国内外煤经合成气间接液化合成液体燃料的开发趋势和工业化状况，讨论了煤间接液化工艺路线和需要解决的关键技术难题，分析了煤间接液化的技术经济性，展望了我国煤间接液化产业化前景。     

Biological conversion of coal and coal-derived synthesis gas

Recent research has resulted in a number of promising biological pathways to produce clean fuels from coal. These processes all involve two or more steps: either the biosolubilization of coal, followed by bioconversion to ethanol or methane; or conversion of coal to synthesis gas, followed by bioconversion into alcohols or methane. Sulfur may also be removed from the solubilized coal or synthesis gas in a separate, or concurrent, biological step. This paper presents research results from both the direct and indirect conversion of coal to liquid fuels using biological processes. A review of direct conversion techniques in producing liquid fuels from coal in a serial conversion process is presented. In addition, bioreactor design data for the conversion of CO, CO₂ and H₂ in synthesis gas by Clostridium ljungdahlii in both batch and continuous culture are reviewed and discussed.