Journal of The Energy Institute最新文献_第5页

Oxygen vacancy modulation for enhanced hydrogen production via chemical looping water-gas shift 通过化学循环水气变换调节氧空位以提高制氢能力

IF 5.6 2区工程技术

Journal of The Energy Institute Pub Date : 2024-09-19 DOI: 10.1016/j.joei.2024.101830

{"title":"Oxygen vacancy modulation for enhanced hydrogen production via chemical looping water-gas shift","authors":"","doi":"10.1016/j.joei.2024.101830","DOIUrl":"10.1016/j.joei.2024.101830","url":null,"abstract":"<div>Chemical looping water gas shift (CL-WGS)is prospective to generate high-purity hydrogen with integrated CO2 capture. However, this technology is impeded by the lack of active oxygen carriers at mid-temperatures. Here, we synthesized several Ni-doped CoFe2O4-δ to modulate oxygen vacancies and investigate its effect on promoting hydrogen production reaction via chemical looping water gas shift at 650 °C. The findings delineate that doping Ni considerably lowers the energy barriers associated with the oxygen vacancies formation, thereby augmenting their concentration. The underlying mechanism elucidates that within the CL-WGS process, the transfer of lattice oxygen acts as the rate-limiting step. NixCo1-xFe2O4 lowers the formation energy of oxygen vacancies and facilitates the bulk lattice oxygen diffusion through the bulk. Hence, Ni0.5Co0.5Fe2O4 demonstrates the most reduction depth and reversibility via redox reactions, resulting in an elevated hydrogen yield (∼15.5 mmol g−1) at 650 °C, which surpasses the yield from undoped CoFe2O4 by 1.4 times. This performance remains consistently high with only a minimal decline over 100 cycles. The findings introduce a promising approach to promote the reactivity of oxygen carriers, particularly for mid-temperature applications.</div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142271690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

ReaxFF simulations on the transformation pathway of nitrogen elements in the heavy tar under oxy-coal combustion 富氧燃烧下重焦油中氮元素转化途径的 ReaxFF 模拟

IF 5.6 2区工程技术

Journal of The Energy Institute Pub Date : 2024-09-19 DOI: 10.1016/j.joei.2024.101837

{"title":"ReaxFF simulations on the transformation pathway of nitrogen elements in the heavy tar under oxy-coal combustion","authors":"","doi":"10.1016/j.joei.2024.101837","DOIUrl":"10.1016/j.joei.2024.101837","url":null,"abstract":"<div>Heavy tar is a crucial intermediate product during coal combustion. To explore the transformation pathway of N atoms in heavy tar under oxy-coal combustion, a comprehensive molecular model of heavy tar with typical N-containing functional groups was constructed. Different temperatures and chemical equivalence ratios were set for the oxy-coal combustion. The ReaxFF was employed to study various products' distribution and molecular numbers. The reaction network among different precursors and NOx was extracted, and the NO to N2 conversion mechanism was summarized. The results indicated that, like char combustion, the proportion of heavy tar gradually declined, the proportion of light tar and organic gas first rose and then gradually declined, and the proportion of inorganic gas continuously rose during heavy tar combustion. As the temperature increased, the proportion of cyanide precursors decreased, while the proportion of amine precursors and NOx increased. The oxidation of N-containing intermediates became more intense as the O2 content rose, but this oxidation effect was inhibited, and the NOx generation was reduced as the O2 content further increased. NO could bond with NHi, HNO, CN, and activate NO, decomposing to produce N2O, and N2O reacted with H radical to produce N2.</div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142271688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Catalytic hydrodeoxygenation of lignin enhanced by selectively etching ZSM-5 通过选择性蚀刻 ZSM-5 强化木质素的催化加氢脱氧反应

IF 5.6 2区工程技术

Journal of The Energy Institute Pub Date : 2024-09-19 DOI: 10.1016/j.joei.2024.101838

{"title":"Catalytic hydrodeoxygenation of lignin enhanced by selectively etching ZSM-5","authors":"","doi":"10.1016/j.joei.2024.101838","DOIUrl":"10.1016/j.joei.2024.101838","url":null,"abstract":"<div>Cyclanes, a major component of aviation fuel, can be obtained from the catalytic hydrodeoxygenation (HDO) of lignin, which not only reduces the dependence on fossil resources, but also makes lignin refining economically viable. The adsorption capacity and dwell times of reactants and H2 on the catalyst play a key role in the HDO of lignin. It remains a difficult challenge to enhance the adsorption capacity of the catalyst for reactants and H2 and to prolong their extended dwell times on the catalyst. Based on this, a nickel-based catalyst with moderate corrosion was prepared by the dissolution of ZSM-5 single crystals induced by ammonia, and was used for value-added conversion of lignin. It was confirmed by experiments and complementary characterizations that the corrosion of Ni/ZSM-5 for etching 2 h (Ni/ZSM-52) enhanced the adsorption capacity of H2 and extended the dwell times of the reactant and H2. Furthermore, the uniformly dispersed Ni nanoparticles stimulated the intrinsic catalytic activity and efficiently generated H…H and H+, which synergistically promote the HDO of lignin with the cyclanes yield up to 58.6 %. As a result, BOB was completely converted to cyclanes over Ni/ZSM-52 at 140 °C under 2 MPa of H2 for 4 h, suggesting Ni/ZSM-52 exhibits excellent HDO activity under mild conditions.</div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142271689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of pyrolysis temperature on migration characteristics of heavy metals during biomass pyrolysis 热解温度对生物质热解过程中重金属迁移特性的影响

IF 5.6 2区工程技术

Journal of The Energy Institute Pub Date : 2024-09-19 DOI: 10.1016/j.joei.2024.101840

引用次数: 0

An experimental investigation of 1,2-dimethoxy ethane as a fuel additive in biodiesel-fueled diesel engine 将 1,2-二甲氧基乙烷作为生物柴油发动机燃料添加剂的实验研究

IF 5.6 2区工程技术

Journal of The Energy Institute Pub Date : 2024-09-19 DOI: 10.1016/j.joei.2024.101824

{"title":"An experimental investigation of 1,2-dimethoxy ethane as a fuel additive in biodiesel-fueled diesel engine","authors":"","doi":"10.1016/j.joei.2024.101824","DOIUrl":"10.1016/j.joei.2024.101824","url":null,"abstract":"<div><div>Recently, researchers have focused on the addition of various additives to biodiesel and other petroleum-derived fuels to improve combustion characteristics and reduce pollutant emissions in internal combustion engines. This study explores the effects of integrating 1,2-dimethoxy ethane (1,2-DME) into reference fuels (RF), including 100 % diesel (D100), 100 % biodiesel (B100), and a blend of 50 % diesel with 50 % biodiesel (B50). In the experiment, 1,2-DME is added at volumes of 5 %, 10 %, and 15 % while engine load is at 25 %, 50 %, and 75 %. In-cylinder pressure and temperature, heat release rate (HRR), knock intensity (RI), combustion duration (CD), ignition delay (ID), brake thermal efficiency (BTE) and pollutant emissions such as carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbon (HC), and smoke opacity are all evaluated. The findings reveal that increasing the 1,2-DME ratio in the reference fuels enhances HRR, in-cylinder pressure, and temperature. Notably, adding 10 % 1,2-DME to D100 at 25 % engine load significantly increases HRR by approximately 28.65 %. Generally, incorporating 1,2-DME reduces ignition delay, shortens ignition duration and intensifies knock (RI). Analysis of pollutant emissions indicates an increase in nitrogen oxide (NOx) emissions but a reductions in carbon monoxide (CO) and hydrocarbon (HC) emissions with 1,2-DME addition. Furthermore, adding 15 % 1,2-DME to D100 at 25 % engine load reduces smoke opacity by 59.2 %. In summary, the significant effects of 1,2-DME on reference fuels indicate its potential as a viable alternative fuel additive.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of ozone and oxygen dilution on soot formation in coflow ethylene/oxygen/ozone laminar partially premixed flames 臭氧和氧气稀释对同流乙烯/氧气/臭氧层流部分预混合火焰中烟尘形成的影响

IF 5.6 2区工程技术

Journal of The Energy Institute Pub Date : 2024-09-19 DOI: 10.1016/j.joei.2024.101832

{"title":"Effect of ozone and oxygen dilution on soot formation in coflow ethylene/oxygen/ozone laminar partially premixed flames","authors":"","doi":"10.1016/j.joei.2024.101832","DOIUrl":"10.1016/j.joei.2024.101832","url":null,"abstract":"<div><div>Ozone is a prospective additive for enhancing and controlling combustion, due to its extremely oxidizing property. Ozone can enhance laminar burning velocity, broaden the flammability limit and improve flame stability, but the effect of ozone on soot formation in the combustion process of hydrocarbon fuels was not yet clear. Therefore, the soot from ethylene/oxygen/ozone laminar partially premixed flames was investigated. Besides, the response law of soot formation to different dilution gas ratios, and the effect of ozone participation in the reaction was also investigated. This work found that ozone significantly shortened the flame height by 4 mm in the cases of 10 % dilution ratio. The particle size of soot was larger at low and medium flame heights due to ozone involved in combustion. The main reason was that ozone promoteed soot growth. At medium and high flame heights, the larger the percentage of oxygen and ozone, the lower graphitization degree of the soot. The addition of oxygen and ozone both made the ID/IG value increase, which indicated the graphitization degree decreased. The soot from high height of the flame with 10 % dilution ratio and the addition of ozone had the largest ID/IG value of 0.970, which indicated a very low degree of graphitization. The signal intensity of the oxygen-containing functional groups on the surface of soot at the high flame height was enhanced with the addition of oxygen and ozone to the reaction.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142314740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental study on co-gasification of cellulose and high-density polyethylene with CO2 纤维素和高密度聚乙烯与二氧化碳共气化实验研究

IF 5.6 2区工程技术

Journal of The Energy Institute Pub Date : 2024-09-19 DOI: 10.1016/j.joei.2024.101839

{"title":"Experimental study on co-gasification of cellulose and high-density polyethylene with CO2","authors":"","doi":"10.1016/j.joei.2024.101839","DOIUrl":"10.1016/j.joei.2024.101839","url":null,"abstract":"<div><div>Co-gasification of biomass and waste plastic with CO2 presents an effective strategy for integrating biomass conversion, waste utilization and carbon recycling. In this study, the co-gasification of cellulose and high-density polyethylene with CO2 was investigated experimentally. The effects of mixing ratio and temperature on co-gasification characteristics, including gas yield, product gas composition, lower heating value of syngas and gasification efficiency, were comprehensively evaluated. Additionally, the interaction between cellulose and high-density polyethylene was analyzed. The results suggested that increasing the polyethylene content in feedstock resulted in decreased yields of H2 and CO, increased CH4 yield, increased lower heating value of syngas and reduced gasification efficiency. The interaction between cellulose and high-density polyethylene enhanced the gas yield, with the most significant effect at 40 % polyethylene content. In the range of 900 °C–1000 °C, increasing the temperature resulted in increased gas yield, reduced lower heating value of syngas and increased gasification efficiency. The positive interaction between cellulose and high-density polyethylene on gas yield was more significant at higher temperatures. This work shed light on reaction characteristics for co-gasification of biomass and high-density polyethylene with CO2, laying the foundation for the design and application of this technology.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Insights into the catalytic mechanism of calcium species during char-H2O/CO2 gasification based on molecular reaction dynamics 基于分子反应动力学揭示炭-H2O/CO2 气化过程中钙物种的催化机理

IF 5.6 2区工程技术

Journal of The Energy Institute Pub Date : 2024-09-18 DOI: 10.1016/j.joei.2024.101831

{"title":"Insights into the catalytic mechanism of calcium species during char-H2O/CO2 gasification based on molecular reaction dynamics","authors":"","doi":"10.1016/j.joei.2024.101831","DOIUrl":"10.1016/j.joei.2024.101831","url":null,"abstract":"<div>Calcium has a definite catalytic effect in char gasification and affects the distribution and composition of gasification products. Therefore, a deep understanding of the reaction properties and mechanism of calcium in gasification is of great significance for the gasification process. Reactive Force Field Molecular Dynamics (ReaxFF MD), an approach for exploring complex chemical reactions, has provided an indispensable aid to the insightful study of the reaction properties of calcium in coal gasification processes. In this work, ReaxFF MD was adopted to construct gasification reactions with different conditions, and the effect of calcium on the products during the gasification was investigated by counting the distribution of the gasification products as well as the changes of calcium species in different conditions. At the same time, the catalytic mechanism of calcium in char during gasification was further investigated by calculating the charge and electrostatic potential of the gasification agent and the gasification agent after calcium binding, as well as the radial distribution function between different atoms. Research has shown that during gasification, the release of calcium from char combined with oxygen atoms in the gasifying agent leads to a decrease in the O–H or C=O bond energy, which promotes the cracking of the gasifying agent. It is worth noting that in comparison to CO2, Ca can easily form ionic bonds with O in the H2O molecule during the gasification process, which leads to easier breaking of the O–H bonds.</div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142271160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical investigation of ammonia-propane cofiring characteristics utilizing air and hydrogen peroxide as oxidizers 利用空气和过氧化氢作为氧化剂对氨-丙烷共烧特性的数值研究

IF 5.6 2区工程技术

Journal of The Energy Institute Pub Date : 2024-09-07 DOI: 10.1016/j.joei.2024.101817

{"title":"Numerical investigation of ammonia-propane cofiring characteristics utilizing air and hydrogen peroxide as oxidizers","authors":"","doi":"10.1016/j.joei.2024.101817","DOIUrl":"10.1016/j.joei.2024.101817","url":null,"abstract":"<div>In the present study, we have investigated the impact of introducing different amounts of hydrogen peroxide into the air on the co-combustion behavior of propane and ammonia. Various combustion criteria including flame speed, ignition delay, heat release, NO emission, and reaction pathways have been explored within different compositions of propane/ammonia/air/hydrogen peroxide. This investigation has been performed through the kinetic study applying a detailed mechanism compromising 188 species and 1604 reactions. According to the findings, air replacement by hydrogen peroxide might improve the laminar burning velocity, heat release rate, flame temperature. The substantial reactivity of hydrogen peroxide leads to a significant increase in OH and H radicals, consequently accelerating the reaction rates as the hydrogen peroxide content in the oxidizer increases. The reaction H + O2↔O + OH (R906) plays the most significant role in enhancing flame propagation in a fuel/air mixture. However, as the hydrogen peroxide content in the mixture increases, the influence of this reaction diminishes, and the reaction H2O2(+M)↔2OH(+M) (R929) becomes more dominant. Initially, NO levels increase with the addition of hydrogen peroxide, but they start to decline at higher proportions of hydrogen peroxide. The initial increase may be attributed to the higher flame temperature, while the subsequent decrease could be linked to a substantial reduction in atmospheric nitrogen levels in the oxidizer. In situations where, pure hydrogen peroxide is used as the oxidizer, there is no production of NOx in pure propane combustion due to the lack of nitrogen. When compared to pure ammonia combustion, cofiring results in approximately half the amount of NOx emissions.</div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142163120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Research on the calculation method of auto-ignition timing and the effect of combustion parameters on auto-ignition under knock condition 爆震条件下自燃时间计算方法及燃烧参数对自燃影响的研究

IF 5.6 2区工程技术

Journal of The Energy Institute Pub Date : 2024-09-05 DOI: 10.1016/j.joei.2024.101818

{"title":"Research on the calculation method of auto-ignition timing and the effect of combustion parameters on auto-ignition under knock condition","authors":"","doi":"10.1016/j.joei.2024.101818","DOIUrl":"10.1016/j.joei.2024.101818","url":null,"abstract":"<div>Auto-ignition triggering plays an important role in the study of knock, accurate and generalized calculation methods are of great significance. In this study, a brand new calculation method of end-mixture auto-ignition timing based on heat release rate (HRR) is proposed based on several sets of data with different knock intensities of a small turbocharged gasoline engine. The calculation method effectively eliminates the effect of fluctuations in the actual HRR data by setting the search range and the auto-ignition threshold, and also eliminates the calculation delay caused by the second-order derivatives of HRR in the regular calculation method. Under this calculation method, the auto-ignition and knock characteristics present a good fit. The effects of combustion parameters on auto-ignition are significantly different. The changes in engine coolant and inlet air temperature as well as the over-rich mixture significantly affected the auto-ignition trigger pressure, while the ignition timing and the over-lean mixture had no effect on it. The effects of methanol on auto-ignition trigger pressure were also significantly different under various injection timings. The calculation of auto-ignition timing provides a vital prerequisite for the study of auto-ignition triggering, which is of obvious significance for the study of knock.</div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142238380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0