Lei Qian, Jun Cheng, Kai Xin, Hao Guo, Yuxiang Mao, Jiacan Tu, Weijuan Yang
Considering the rapid growth and high oil content of microalgae, biodiesel production from microalgal oil is a key technology to address declining crude oil resources and environmental pollution. To enhance the low-temperature activity of Zr based metal–organic framework (Zr-MOFs), we employed a simple and versatile one-pot synthesis approach to fabricate mixed-valence Ce-doped MOF-808 with enhanced bridging hydroxyl groups, for the conversion of microalgal lipids at significantly reduced temperatures. Density functional theory calculations revealed that successful doping of Ce(III) ions facilitated electronic delocalization of neighboring atoms in Zr/Ce-MOF-808, lowering the activation temperature of methanol and forming a unique electron-rich bridging hydroxyl structure, thereby greatly enhancing low-temperature activity. Compared to pristine MOF-808, Zr/Ce (1 : 1)-MOF-808 exhibited a catalytic conversion efficiency increase from 8.34% to 89.51% at 100 °C, significantly reducing reactor pressure from 4036 kPa at 200 °C to 352 kPa at 100 °C. With indirect contact established between the catalyst's metal centers and reactants, the catalyst demonstrated only a 3% decrease in conversion efficiency after five cycles of use.
考虑到微藻的快速生长和高含油量，利用微藻油生产生物柴油是解决原油资源减少和环境污染问题的关键技术。为了提高锆基金属有机框架（Zr-MOFs）的低温活性，我们采用了一种简单、多用途的一锅合成方法，制备了掺杂混合价铈的 MOF-808，并增强了桥接羟基，用于在显著降低的温度下转化微藻脂质。密度泛函理论计算表明，成功掺入 Ce(III) 离子可促进 Zr/Ce-MOF-808 中邻近原子的电子脱ocal，降低甲醇的活化温度，形成独特的富电子桥接羟基结构，从而大大提高低温活性。与原始 MOF-808 相比，Zr/Ce（1:1）-MOF-808 在 100 °C 时的催化转化效率从 8.34% 提高到 89.51%，反应器压力从 200 °C 时的 4036 kPa 显著降低到 100 °C 时的 352 kPa。由于催化剂的金属中心与反应物之间建立了间接接触，催化剂在使用五个周期后，转化效率仅降低了 3%。
{"title":"Enhanced hydroxyl bridge-mediated microalgal lipid conversion via mixed-valence Zr/Ce-MOF-808 catalysts at reduced temperatures","authors":"Lei Qian, Jun Cheng, Kai Xin, Hao Guo, Yuxiang Mao, Jiacan Tu, Weijuan Yang","doi":"10.1039/d4se00647j","DOIUrl":"https://doi.org/10.1039/d4se00647j","url":null,"abstract":"Considering the rapid growth and high oil content of microalgae, biodiesel production from microalgal oil is a key technology to address declining crude oil resources and environmental pollution. To enhance the low-temperature activity of Zr based metal–organic framework (Zr-MOFs), we employed a simple and versatile one-pot synthesis approach to fabricate mixed-valence Ce-doped MOF-808 with enhanced bridging hydroxyl groups, for the conversion of microalgal lipids at significantly reduced temperatures. Density functional theory calculations revealed that successful doping of Ce(<small>III</small>) ions facilitated electronic delocalization of neighboring atoms in Zr/Ce-MOF-808, lowering the activation temperature of methanol and forming a unique electron-rich bridging hydroxyl structure, thereby greatly enhancing low-temperature activity. Compared to pristine MOF-808, Zr/Ce (1 : 1)-MOF-808 exhibited a catalytic conversion efficiency increase from 8.34% to 89.51% at 100 °C, significantly reducing reactor pressure from 4036 kPa at 200 °C to 352 kPa at 100 °C. With indirect contact established between the catalyst's metal centers and reactants, the catalyst demonstrated only a 3% decrease in conversion efficiency after five cycles of use.","PeriodicalId":104,"journal":{"name":"Sustainable Energy & Fuels","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141506691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Photoelectrochemical (PEC) water splitting is an immensely effective method for producing hydrogen. In this study, we present the fabrication of an efficient photoanode based on a g-C3N4/Bi2S3/ZnS ternary heterojunction system using the doctor blade technique in combination with the successive ionic layer adsorption and reaction (SILAR) method. This ternary heterojunction demonstrated outstanding PEC performance, exhibiting a remarkable photocurrent density of 13.48 mA cm−2 at 1.23 V vs. RHE in an alkaline medium. The enhanced photocurrent in the presence of hole scavengers could be due to sulfite oxidation. ZnS serves the dual purpose of acting as a passivation layer to prevent direct contact between Bi2S3 and the electrolyte and offering an additional active energy state to enhance charge density, thus lending operational stability to the photoanode. The incident photon-to-current efficiency (IPCE) of the g-C3N4/Bi2S3/ZnS photoanode is 2.98%, which is substantially greater than 0.69% obtained with the g-C3N4/Bi2S3 system. The g-C3N4/Bi2S3/ZnS photoanode exhibited a 94.6% average faradaic efficiency and high stability for up to 5000 seconds. Furthermore, electrochemical impedance spectroscopy (EIS) and photoluminescence (PL) studies revealed efficient electron transfer at the heterojunction and thus were in accordance with the observed enhancement of the photocurrent density of the fabricated electrodes.
{"title":"Rational design of a g-C3N4/Bi2S3/ZnS ternary heterojunction photoanode for improved solar water splitting","authors":"Merin Joseph, Bhagatram Meena, Rosmy Joy, Sneha Joseph, Rajesh Kumar Sethi, Sebastian Nybin Remello, Suja Haridas, Challapalli Subrahmanyam","doi":"10.1039/d4se00147h","DOIUrl":"https://doi.org/10.1039/d4se00147h","url":null,"abstract":"Photoelectrochemical (PEC) water splitting is an immensely effective method for producing hydrogen. In this study, we present the fabrication of an efficient photoanode based on a g-C<small><sub>3</sub></small>N<small><sub>4</sub></small>/Bi<small><sub>2</sub></small>S<small><sub>3</sub></small>/ZnS ternary heterojunction system using the doctor blade technique in combination with the successive ionic layer adsorption and reaction (SILAR) method. This ternary heterojunction demonstrated outstanding PEC performance, exhibiting a remarkable photocurrent density of 13.48 mA cm<small><sup>−2</sup></small> at 1.23 V <em>vs.</em> RHE in an alkaline medium. The enhanced photocurrent in the presence of hole scavengers could be due to sulfite oxidation. ZnS serves the dual purpose of acting as a passivation layer to prevent direct contact between Bi<small><sub>2</sub></small>S<small><sub>3</sub></small> and the electrolyte and offering an additional active energy state to enhance charge density, thus lending operational stability to the photoanode. The incident photon-to-current efficiency (IPCE) of the g-C<small><sub>3</sub></small>N<small><sub>4</sub></small>/Bi<small><sub>2</sub></small>S<small><sub>3</sub></small>/ZnS photoanode is 2.98%, which is substantially greater than 0.69% obtained with the g-C<small><sub>3</sub></small>N<small><sub>4</sub></small>/Bi<small><sub>2</sub></small>S<small><sub>3</sub></small> system. The g-C<small><sub>3</sub></small>N<small><sub>4</sub></small>/Bi<small><sub>2</sub></small>S<small><sub>3</sub></small>/ZnS photoanode exhibited a 94.6% average faradaic efficiency and high stability for up to 5000 seconds. Furthermore, electrochemical impedance spectroscopy (EIS) and photoluminescence (PL) studies revealed efficient electron transfer at the heterojunction and thus were in accordance with the observed enhancement of the photocurrent density of the fabricated electrodes.","PeriodicalId":104,"journal":{"name":"Sustainable Energy & Fuels","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141527954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anne Lichtinger, Maximilian J. Poller, Olaf Schröder, Julian Türck, Thomas Garbe, Jürgen Krahl, Markus Jakob, Jakob Albert
The decarbonization of the energy supply is one of the biggest and most important challenges of the 21st century. This paper contributes to the solution of the energy crisis by investigating the stability of alcohols as e-fuels. The focus is on the investigation of the aging mechanism of the linear alcohols 1-hexanol and 1-octanol compared to the iso-alcohol 2-hexanol. It is analysed in detail how the time-dependent aging varies depending on the chain length and the position of the hydroxy-group, both in the liquid and in the gas phase. It is shown that a variety of aging products such as aldehydes, acids, short-chain alcohols and esters are formed during the aging of the n-alcohols by oxidation, decarboxylation, oxidative C–C bond cleavage and esterification. In contrast, the decomposition of the iso-alcohol is significantly lower. The results show that the total acid number is significantly higher for aged n-alcohols than for the aged iso-alcohos, while the kinematic viscosity decreases for all alcohols during aging. Carbon mass balancing shows that after accelerated aging for 120 hours, around 80% of the iso-alcohol is still present, compared to only around 57–63% for the n-alcohols. In addition, significantly fewer acids are formed with the iso-alcohol. In this study, iso-alcohols have a higher stability against thermo-oxidative aging compared to n-alcohols, showing their potential as e-fuels. Furthermore, the chain length of the alcohols has also an influence on aging, as more different aging products can be formed with increasing chain length.
{"title":"Thermo-oxidative aging of linear and branched alcohols as stability criterion for their use as e-fuels","authors":"Anne Lichtinger, Maximilian J. Poller, Olaf Schröder, Julian Türck, Thomas Garbe, Jürgen Krahl, Markus Jakob, Jakob Albert","doi":"10.1039/d4se00400k","DOIUrl":"https://doi.org/10.1039/d4se00400k","url":null,"abstract":"The decarbonization of the energy supply is one of the biggest and most important challenges of the 21st century. This paper contributes to the solution of the energy crisis by investigating the stability of alcohols as e-fuels. The focus is on the investigation of the aging mechanism of the linear alcohols 1-hexanol and 1-octanol compared to the iso-alcohol 2-hexanol. It is analysed in detail how the time-dependent aging varies depending on the chain length and the position of the hydroxy-group, both in the liquid and in the gas phase. It is shown that a variety of aging products such as aldehydes, acids, short-chain alcohols and esters are formed during the aging of the <em>n</em>-alcohols by oxidation, decarboxylation, oxidative C–C bond cleavage and esterification. In contrast, the decomposition of the iso-alcohol is significantly lower. The results show that the total acid number is significantly higher for aged <em>n</em>-alcohols than for the aged iso-alcohos, while the kinematic viscosity decreases for all alcohols during aging. Carbon mass balancing shows that after accelerated aging for 120 hours, around 80% of the iso-alcohol is still present, compared to only around 57–63% for the <em>n</em>-alcohols. In addition, significantly fewer acids are formed with the iso-alcohol. In this study, iso-alcohols have a higher stability against thermo-oxidative aging compared to <em>n</em>-alcohols, showing their potential as e-fuels. Furthermore, the chain length of the alcohols has also an influence on aging, as more different aging products can be formed with increasing chain length.","PeriodicalId":104,"journal":{"name":"Sustainable Energy & Fuels","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141528027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The development of technologies for the bio-oil upgrading process is a crucial step towards achieving sustainable energy production. This study investigates the effects of support properties during the hydrodeoxygenation (HDO) of benzoic acid as a bio-oil model compound with the aim to produce a catalyst of superior activity and selectivity. Three Ni-based catalysts were prepared: microporous m-Ni/ZSM-5, mesoporous h-Ni/ZSM-5, and Ni/SiO2. The h-Ni/ZSM-5 exhibited the highest concentration of acid sites, strongest metal-support interaction and best metal dispersion. The highest conversion of benzoic acid was recorded over the h-Ni/ZSM-5 catalyst (97%). Ni/SiO2 catalysts produced toluene, while others produced benzene and cyclohexane in addition. This was linked to a synergy between support acidity and metal sites. The catalyst from the nearly neutral support, Ni/SiO2, showed higher activity (91% conversion) compared to m-Ni/ZSM-5 (84%), which was attributed to the mesoporous nature of Ni/SiO2, allowing more access to active sites for bulk benzoic acid molecules. A kinetic model was developed using the Langmuir–Hinshelwood–Hougen–Watson (LHHW) approach. A mechanism assuming dual-site adsorption of dissociatively adsorbed hydrogen was shown to be the most accurate representation of the three-phase benzoic acid HDO. The observed activation energy from the model was 137.2 kJ mol−1.
{"title":"Catalytic hydrodeoxygenation of benzoic acid as a bio-oil model compound: reaction and kinetics using nickel-supported catalysts","authors":"Mustapha Yusuf, Gary A. Leeke, Joseph Wood","doi":"10.1039/d4se00589a","DOIUrl":"https://doi.org/10.1039/d4se00589a","url":null,"abstract":"The development of technologies for the bio-oil upgrading process is a crucial step towards achieving sustainable energy production. This study investigates the effects of support properties during the hydrodeoxygenation (HDO) of benzoic acid as a bio-oil model compound with the aim to produce a catalyst of superior activity and selectivity. Three Ni-based catalysts were prepared: microporous m-Ni/ZSM-5, mesoporous h-Ni/ZSM-5, and Ni/SiO<small><sub>2</sub></small>. The h-Ni/ZSM-5 exhibited the highest concentration of acid sites, strongest metal-support interaction and best metal dispersion. The highest conversion of benzoic acid was recorded over the h-Ni/ZSM-5 catalyst (97%). Ni/SiO<small><sub>2</sub></small> catalysts produced toluene, while others produced benzene and cyclohexane in addition. This was linked to a synergy between support acidity and metal sites. The catalyst from the nearly neutral support, Ni/SiO<small><sub>2</sub></small>, showed higher activity (91% conversion) compared to m-Ni/ZSM-5 (84%), which was attributed to the mesoporous nature of Ni/SiO<small><sub>2</sub></small>, allowing more access to active sites for bulk benzoic acid molecules. A kinetic model was developed using the Langmuir–Hinshelwood–Hougen–Watson (LHHW) approach. A mechanism assuming dual-site adsorption of dissociatively adsorbed hydrogen was shown to be the most accurate representation of the three-phase benzoic acid HDO. The observed activation energy from the model was 137.2 kJ mol<small><sup>−1</sup></small>.","PeriodicalId":104,"journal":{"name":"Sustainable Energy & Fuels","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141528101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Extensive exploration has been conducted on MXenes to comprehend their inherent physical and chemical properties, leading to the discovery of their diverse functional applications across various domains. MXenes have been investigated for hydrogen production and storage applications with nitrogen reduction, showing promising adsorption capacities and kinetics. With continued innovation and collaboration, MXenes hold the potential to drive the transition towards a sustainable hydrogen economy. Its use in catalysis is especially intriguing due to its active surfaces, which offer ample opportunities for catalytic reactions for HER, OER and NRR. By leveraging the unique properties of MXenes, efforts have been made to produce cost-effective and scalable solutions for hydrogen evolution and storage. However, despite their potential, numerous critical issues persist in both theoretical understanding and experimental implementation, hindering their practical applications. One such challenge lies in the development of efficient and scalable methods for producing MXenes in an environmentally friendly manner. Given the current limitations in production volume, leveraging MXenes as co-catalysts appears promising, requiring only minimal quantities. Furthermore, blending MXenes with other materials to form composites holds promise for enhancing performance. Moving forward, it is imperative to delve deeper into theoretical and experimental investigations addressing these challenges and exploring novel tuning strategies for MXenes.
{"title":"Applications of MXenes in Hydrogen evolution/ Oxygen evolution and Nitrogen reduction reactions","authors":"Divya Bajpai Tripathy","doi":"10.1039/d4se00556b","DOIUrl":"https://doi.org/10.1039/d4se00556b","url":null,"abstract":"Extensive exploration has been conducted on MXenes to comprehend their inherent physical and chemical properties, leading to the discovery of their diverse functional applications across various domains. MXenes have been investigated for hydrogen production and storage applications with nitrogen reduction, showing promising adsorption capacities and kinetics. With continued innovation and collaboration, MXenes hold the potential to drive the transition towards a sustainable hydrogen economy. Its use in catalysis is especially intriguing due to its active surfaces, which offer ample opportunities for catalytic reactions for HER, OER and NRR. By leveraging the unique properties of MXenes, efforts have been made to produce cost-effective and scalable solutions for hydrogen evolution and storage. However, despite their potential, numerous critical issues persist in both theoretical understanding and experimental implementation, hindering their practical applications. One such challenge lies in the development of efficient and scalable methods for producing MXenes in an environmentally friendly manner. Given the current limitations in production volume, leveraging MXenes as co-catalysts appears promising, requiring only minimal quantities. Furthermore, blending MXenes with other materials to form composites holds promise for enhancing performance. Moving forward, it is imperative to delve deeper into theoretical and experimental investigations addressing these challenges and exploring novel tuning strategies for MXenes.","PeriodicalId":104,"journal":{"name":"Sustainable Energy & Fuels","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141528098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nimish Milind Pankhedkar, Rohan Sartape, Meenesh R. Singh, Ravindra D Gudi, Pratim Biswas
The increase in greenhouse gas emissions and the subsequent global warming effects necessitate effective carbon dioxide (CO2) mitigation strategies such as CO2 capture and CO2 utilization. Chemical Looping Combustion (CLC) is a promising technology that offers a low-cost and effective CO2 capture while also generating power. With an increase in attention towards utilization of captured CO2, this paper presents a novel polygeneration process integrating CLC with electrochemical CO2 conversion for simultaneous power generation and production of valuable chemicals. This integration leverages the inherent CO2 capture capability of CLC, providing low-cost capture while enabling the valorization of captured CO2 into ethylene. A detailed techno-economic feasibility of this approach has been analyzed based on experimental data that has been utilized to develop a grey-box model for electrolysis. The overall process has been simulated using Aspen Plus along with the conventional process that generate power using conventional coal fired boilers coupled with amine-based CO2 capture followed by valorization of CO2 via similar electro-reduction unit as that in proposed process, thus presenting a relative analysis between the conventional CCUS and proposed CLC-based CCUS approaches. The performance indicators have been defined that exhibit a trade-off between the CO2 valorization and power generation while yielding efficiencies of proposed process 9.16 % points higher than the conventional variant. Furthermore, the polygeneration process demonstrated a feasible CO2¬ valorization up to 15% while compromising the power generation. The economic assessments indicate a 21.6 % reduction in the total annualized investment relative to the conventional process.
{"title":"System-level feasibility analysis of a novel chemical looping combustion integrated with electrochemical CO2 reduction","authors":"Nimish Milind Pankhedkar, Rohan Sartape, Meenesh R. Singh, Ravindra D Gudi, Pratim Biswas","doi":"10.1039/d4se00770k","DOIUrl":"https://doi.org/10.1039/d4se00770k","url":null,"abstract":"The increase in greenhouse gas emissions and the subsequent global warming effects necessitate effective carbon dioxide (CO2) mitigation strategies such as CO2 capture and CO2 utilization. Chemical Looping Combustion (CLC) is a promising technology that offers a low-cost and effective CO2 capture while also generating power. With an increase in attention towards utilization of captured CO2, this paper presents a novel polygeneration process integrating CLC with electrochemical CO2 conversion for simultaneous power generation and production of valuable chemicals. This integration leverages the inherent CO2 capture capability of CLC, providing low-cost capture while enabling the valorization of captured CO2 into ethylene. A detailed techno-economic feasibility of this approach has been analyzed based on experimental data that has been utilized to develop a grey-box model for electrolysis. The overall process has been simulated using Aspen Plus along with the conventional process that generate power using conventional coal fired boilers coupled with amine-based CO2 capture followed by valorization of CO2 via similar electro-reduction unit as that in proposed process, thus presenting a relative analysis between the conventional CCUS and proposed CLC-based CCUS approaches. The performance indicators have been defined that exhibit a trade-off between the CO2 valorization and power generation while yielding efficiencies of proposed process 9.16 % points higher than the conventional variant. Furthermore, the polygeneration process demonstrated a feasible CO2¬ valorization up to 15% while compromising the power generation. The economic assessments indicate a 21.6 % reduction in the total annualized investment relative to the conventional process.","PeriodicalId":104,"journal":{"name":"Sustainable Energy & Fuels","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141528097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Uriah Kilgore, Emily Diaz, Ben Spry, Yuan Jiang, Shuyun Li, Andrew Schmidt, Michael R. Thorson
Hydrothermal liquefaction (HTL) is a technology capable of producing sustainable hydrocarbon fuels from wet waste, reducing volumes of that waste as an added benefit. However, sustainable fuel production through HTL has yet to reach commercial scale and opportunities for improvements to process safety remain. This work describes low-pressure, low-temperature, two-stage solvent extraction and separation of HTL products utilizing naphtha range hydrocarbons. The similar qualitative solubility behavior of bitumen and biocrude (BC) with respect to paraffin versus naphthene or aromatic solvent composition allows us to examine a process comparable to solvent processing of bitumen. Lab-scale experiments were carried out to demonstrate the basic process and evaluate key parameters. The laboratory work indicates that using aliphatic/aromatic solvent mixtures at 80 °C results in a recovery of nearly 100% of the biocrude from the product mixture with reduced carbon content on the hydro-char. The findings illustrate the potential of solvent extraction for HTL biocrude processing. On a commercial scale, such a process may de-risk HTL, improving prospects for commercialization, opening the door to widespread conversion of wet-waste and waste biomass to sustainable fuels by HTL.
水热液化（HTL）是一种能够利用湿废物生产可持续碳氢化合物燃料的技术，同时还能减少废物量。然而，通过热液化技术生产可持续燃料的规模尚未达到商业化水平，改进工艺安全性的机会依然存在。本研究介绍了利用石脑油系列碳氢化合物对 HTL 产品进行低压、低温、两级溶剂萃取和分离的方法。沥青和生物原油（BC）在石蜡与石脑油或芳烃溶剂成分方面具有相似的定性溶解行为，这使我们能够研究与沥青溶剂加工类似的工艺。我们进行了实验室规模的实验，以演示基本工艺并评估关键参数。实验室工作表明，在 80 °C 温度下使用脂肪族/芳香族溶剂混合物，可从产品混合物中回收近 100% 的生物原油，同时降低碳氢化合物的含量。研究结果表明了溶剂萃取在高温液化生物原油加工中的潜力。在商业规模上，这种工艺可以降低高温热解工艺的风险，改善商业化前景，为通过高温热解工艺将湿废物和废弃生物质广泛转化为可持续燃料打开大门。
{"title":"Solvent processing for improved separation of hydrothermal liquefaction products","authors":"Uriah Kilgore, Emily Diaz, Ben Spry, Yuan Jiang, Shuyun Li, Andrew Schmidt, Michael R. Thorson","doi":"10.1039/d4se00516c","DOIUrl":"https://doi.org/10.1039/d4se00516c","url":null,"abstract":"Hydrothermal liquefaction (HTL) is a technology capable of producing sustainable hydrocarbon fuels from wet waste, reducing volumes of that waste as an added benefit. However, sustainable fuel production through HTL has yet to reach commercial scale and opportunities for improvements to process safety remain. This work describes low-pressure, low-temperature, two-stage solvent extraction and separation of HTL products utilizing naphtha range hydrocarbons. The similar qualitative solubility behavior of bitumen and biocrude (BC) with respect to paraffin <em>versus</em> naphthene or aromatic solvent composition allows us to examine a process comparable to solvent processing of bitumen. Lab-scale experiments were carried out to demonstrate the basic process and evaluate key parameters. The laboratory work indicates that using aliphatic/aromatic solvent mixtures at 80 °C results in a recovery of nearly 100% of the biocrude from the product mixture with reduced carbon content on the hydro-char. The findings illustrate the potential of solvent extraction for HTL biocrude processing. On a commercial scale, such a process may de-risk HTL, improving prospects for commercialization, opening the door to widespread conversion of wet-waste and waste biomass to sustainable fuels by HTL.","PeriodicalId":104,"journal":{"name":"Sustainable Energy & Fuels","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141528099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ahmed Al-Fatesh, Ibrahim Aidid, Mohammed O. Bayazed, Ahmed Abasaeed, Maher M. Alrashed, Mohammed F. Alotibib, Anis H. Fakeeha, Ahmed I. Osman
The urgent challenge to mitigate fossil fuel emissions for environmental preservation has never been more crucial. Fossil fuels are a significant contributor to climate change because of their greenhouse gas (GHG) emissions. They have a significant negative impact on our environment. Burning fossil fuels releases heat-trapping greenhouse gases such as carbon dioxide, which worsens climate change. Additionally, the extraction processes for fossil fuels pollute the air we breathe by emitting harmful substances into the atmosphere. As a result, sustainable alternatives are necessary. One promising alternative is the dry reforming of methane (DRM), which converts two GHGs, CH₄ and CO₂, into syngas, a valuable chemical feedstock. However, efficient and selective DRM requires optimized catalyst performance. While existing research explores Ni catalysts for DRM, there is a gap in identifying optimal promoters that maximize conversion rates and achieve the ideal H₂/CO ratio for syngas production. To address this gap, we investigated Ni catalysts supported on silica-alumina (SiAl) composites, incorporating Ir, Rh, Ru, Pt, and Pd as promoters. We used a central composite design technique to optimize the DRM process. Characterization techniques, including N₂ adsorption, XRD, H₂-TPR, CO₂-TPD, Raman, TGA, SEM, and TEM, were used to analyze the catalysts' properties. Our research aimed to identify the most effective metal promoter for Ni catalysts in DRM, optimize the DRM process for high CH₄ and CO₂ conversion rates while achieving a suitable H₂/CO ratio for syngas production, and evaluate catalyst properties using various characterization techniques. Our results showed that Rh-promoted Ni catalysts displayed superior performance, achieving CH₄ (87.0%) and CO₂ (93.1%) conversion rates under optimized conditions. The H₂/CO ratio of 0.99 indicates ideal syngas composition. Characterization techniques confirmed these findings and revealed the catalysts' efficacy and durability.
{"title":"Sustainable Syngas Generation from Methane: Enhanced Catalysis with Metal-Promoted Nickel on Silica-Alumina Composites","authors":"Ahmed Al-Fatesh, Ibrahim Aidid, Mohammed O. Bayazed, Ahmed Abasaeed, Maher M. Alrashed, Mohammed F. Alotibib, Anis H. Fakeeha, Ahmed I. Osman","doi":"10.1039/d4se00529e","DOIUrl":"https://doi.org/10.1039/d4se00529e","url":null,"abstract":"The urgent challenge to mitigate fossil fuel emissions for environmental preservation has never been more crucial. Fossil fuels are a significant contributor to climate change because of their greenhouse gas (GHG) emissions. They have a significant negative impact on our environment. Burning fossil fuels releases heat-trapping greenhouse gases such as carbon dioxide, which worsens climate change. Additionally, the extraction processes for fossil fuels pollute the air we breathe by emitting harmful substances into the atmosphere. As a result, sustainable alternatives are necessary. One promising alternative is the dry reforming of methane (DRM), which converts two GHGs, CH₄ and CO₂, into syngas, a valuable chemical feedstock. However, efficient and selective DRM requires optimized catalyst performance. While existing research explores Ni catalysts for DRM, there is a gap in identifying optimal promoters that maximize conversion rates and achieve the ideal H₂/CO ratio for syngas production. To address this gap, we investigated Ni catalysts supported on silica-alumina (SiAl) composites, incorporating Ir, Rh, Ru, Pt, and Pd as promoters. We used a central composite design technique to optimize the DRM process. Characterization techniques, including N₂ adsorption, XRD, H₂-TPR, CO₂-TPD, Raman, TGA, SEM, and TEM, were used to analyze the catalysts' properties. Our research aimed to identify the most effective metal promoter for Ni catalysts in DRM, optimize the DRM process for high CH₄ and CO₂ conversion rates while achieving a suitable H₂/CO ratio for syngas production, and evaluate catalyst properties using various characterization techniques. Our results showed that Rh-promoted Ni catalysts displayed superior performance, achieving CH₄ (87.0%) and CO₂ (93.1%) conversion rates under optimized conditions. The H₂/CO ratio of 0.99 indicates ideal syngas composition. Characterization techniques confirmed these findings and revealed the catalysts' efficacy and durability.","PeriodicalId":104,"journal":{"name":"Sustainable Energy & Fuels","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141529443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annalisa Polo, Maria Vittoria Dozzi, Gianluigi Marra, Kevin Sivula, Elena Selli
A systematic investigation on the photoelectrocatalytic (PEC) performance of a series of CuW1−xMoxO4 materials with different Mo for W substitution (x = 0–0.8), successfully synthesized as single, transparent photoactive layers, allowed us to identify copper molybdo-tungstate with x = 0.5 (CuW0.5Mo0.5O4) as the best performing Mo-containing CuWO4-based material for photoanodes fabrication. For 250 nm thick material, the CuW0.5Mo0.5O4 exhibits a 6-fold photocurrent increase at 1.23 V vs. RHE with respect to pure CuWO4. Both PEC analyses in the presence of NaNO2 as sacrificial agent and intensity modulated photocurrent spectroscopy (IMPS) measurements, here applied to this class of materials for the first time, demonstrate that the superior PEC performance of CuW0.5Mo0.5O4 stems from a more efficient separation of photoproduced charges with respect to CuWO4, while the charge injection efficiency is close to 100% for both materials. Further enhanced separation of photoproduced charges, resulting in increased PEC performance of the CuW0.5Mo0.5O4 electrode in the 400–480 nm wavelength range, can be achieved by coupling it with BiVO4, to form a type II heterojunction system.
{"title":"Improving the photoelectrocatalytic efficiency of CuWO4 through molybdenum for tungsten substitution and coupling with BiVO4","authors":"Annalisa Polo, Maria Vittoria Dozzi, Gianluigi Marra, Kevin Sivula, Elena Selli","doi":"10.1039/d4se00161c","DOIUrl":"https://doi.org/10.1039/d4se00161c","url":null,"abstract":"A systematic investigation on the photoelectrocatalytic (PEC) performance of a series of CuW<small><sub>1−<em>x</em></sub></small>Mo<small><sub><em>x</em></sub></small>O<small><sub>4</sub></small> materials with different Mo for W substitution (<em>x</em> = 0–0.8), successfully synthesized as single, transparent photoactive layers, allowed us to identify copper molybdo-tungstate with <em>x</em> = 0.5 (CuW<small><sub>0.5</sub></small>Mo<small><sub>0.5</sub></small>O<small><sub>4</sub></small>) as the best performing Mo-containing CuWO<small><sub>4</sub></small>-based material for photoanodes fabrication. For 250 nm thick material, the CuW<small><sub>0.5</sub></small>Mo<small><sub>0.5</sub></small>O<small><sub>4</sub></small> exhibits a 6-fold photocurrent increase at 1.23 V <em>vs.</em> RHE with respect to pure CuWO<small><sub>4</sub></small>. Both PEC analyses in the presence of NaNO<small><sub>2</sub></small> as sacrificial agent and intensity modulated photocurrent spectroscopy (IMPS) measurements, here applied to this class of materials for the first time, demonstrate that the superior PEC performance of CuW<small><sub>0.5</sub></small>Mo<small><sub>0.5</sub></small>O<small><sub>4</sub></small> stems from a more efficient separation of photoproduced charges with respect to CuWO<small><sub>4</sub></small>, while the charge injection efficiency is close to 100% for both materials. Further enhanced separation of photoproduced charges, resulting in increased PEC performance of the CuW<small><sub>0.5</sub></small>Mo<small><sub>0.5</sub></small>O<small><sub>4</sub></small> electrode in the 400–480 nm wavelength range, can be achieved by coupling it with BiVO<small><sub>4</sub></small>, to form a type II heterojunction system.","PeriodicalId":104,"journal":{"name":"Sustainable Energy & Fuels","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141528100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Reports of dry reforming of methane, ethane, and propane to synthesis gas using the same catalyst are very limited in the open literature. The present study is basically a comparative analysis of methane, ethane and propane for dry reforming reaction considering the catalyst 40Ni0.75(Ce0.75Fe0.25)0.25/Al2O3 and under similar operating conditions. A series of catalysts denoted as 40Ni0.75(Ce1−xFex)0.25/Al2O3 (where x = 0, 0.25, 0.5, 0.75, 1) were synthesized via the sol–gel method, and their catalytic efficacy was assessed for the dry reforming of aliphatic saturated hydrocarbons (methane, ethane, and propane). Comprehensive catalyst characterization resulted through the BET, XRD, H2-TPR, CO2-TPD, Raman spectroscopy, TGA, and FE-SEM analyses. The study revealed that the Ni–Ce species were effectively dispersed over the alumina support. The robust interactions between the nickel and the support significantly enhanced the nickel dispersion and stability. In addition to syngas, the formation of CNTs was also witnessed on the used catalyst's surface, a finding substantiated through FE-SEM and Raman spectral analysis. In the dry reforming of methane (DRM), CO2 exhibited superior conversion compared to methane, whereas in the dry reforming of ethane (DRE) and propane (DRP), the conversion of ethane and propane, respectively, was predominant. The incorporation of a minimal iron fraction into the catalyst exhibited pronounced enhancements in catalytic performance, with the catalyst containing ceria–iron (x = 0.25) manifesting the highest product yield and conversion percentages (HC and CO2).
{"title":"Dry reforming of HCs (methane, ethane, and propane) over a 40Ni0.75(Ce1−xFex)0.25/Al2O3 catalyst: a comparative study","authors":"Akanksha Singh Rajput, Taraknath Das","doi":"10.1039/d4se00467a","DOIUrl":"https://doi.org/10.1039/d4se00467a","url":null,"abstract":"Reports of dry reforming of methane, ethane, and propane to synthesis gas using the same catalyst are very limited in the open literature. The present study is basically a comparative analysis of methane, ethane and propane for dry reforming reaction considering the catalyst 40Ni<small><sub>0.75</sub></small>(Ce<small><sub>0.75</sub></small>Fe<small><sub>0.25</sub></small>)<small><sub>0.25</sub></small>/Al<small><sub>2</sub></small>O<small><sub>3</sub></small> and under similar operating conditions. A series of catalysts denoted as 40Ni<small><sub>0.75</sub></small>(Ce<small><sub>1−<em>x</em></sub></small>Fe<small><sub><em>x</em></sub></small>)<small><sub>0.25</sub></small>/Al<small><sub>2</sub></small>O<small><sub>3</sub></small> (where <em>x</em> = 0, 0.25, 0.5, 0.75, 1) were synthesized <em>via</em> the sol–gel method, and their catalytic efficacy was assessed for the dry reforming of aliphatic saturated hydrocarbons (methane, ethane, and propane). Comprehensive catalyst characterization resulted through the BET, XRD, H<small><sub>2</sub></small>-TPR, CO<small><sub>2</sub></small>-TPD, Raman spectroscopy, TGA, and FE-SEM analyses. The study revealed that the Ni–Ce species were effectively dispersed over the alumina support. The robust interactions between the nickel and the support significantly enhanced the nickel dispersion and stability. In addition to syngas, the formation of CNTs was also witnessed on the used catalyst's surface, a finding substantiated through FE-SEM and Raman spectral analysis. In the dry reforming of methane (DRM), CO<small><sub>2</sub></small> exhibited superior conversion compared to methane, whereas in the dry reforming of ethane (DRE) and propane (DRP), the conversion of ethane and propane, respectively, was predominant. The incorporation of a minimal iron fraction into the catalyst exhibited pronounced enhancements in catalytic performance, with the catalyst containing ceria–iron (<em>x</em> = 0.25) manifesting the highest product yield and conversion percentages (HC and CO<small><sub>2</sub></small>).","PeriodicalId":104,"journal":{"name":"Sustainable Energy & Fuels","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141528102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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