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Hydrochar and synthetic natural gas co-production for a full circular economy implementation via hydrothermal carbonization and methanation:An economic approach

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Journal of Environmental Sciences 2024年第6期140卷 69-78页

作者： Judith González-Arias Guillermo Torres-Sempere Miriam González-Castaño Francisco MBaena-Moreno Tomás RReina Inorganic chemistry Department and Materials Sciences institute University of Seville-CSICSevilleSpain Materials Sciences institute(ICMSE) CSIC-University of SevilleSevilleSpain Department of chemistry and Chemical Engineering Chalmers University of TechnologyGothenburgSE 41296Sweden

Herein we study the economic performance of hydrochar and synthetic natural gas coproduction from olive tree pruning.The process entails a combination of hydrothermal carbonization and methanation.In a previous work,we evidenced that standalone hydrochar production via HTC results unprofitable.Hence,we propose a step forward on the process design by implementing a methanation,adding value to the gas effluent in an attempt to boost the overall process techno-economic aspects.Three different plant capacities were analyzed(312.5,625 and 1250 kg/hr).The baseline scenarios showed that,under the current circumstances,our circular economy strategy in unprofitable.An analysis of the revenues shows that hydrochar selling price have a high impact on NPV and subsidies for renewable coal production could help to boost the profitability of the process.On the contrary,the analysis for natural gas prices reveals that prices 8 times higher than the current ones in Spain must be achieved to reach profitability.This seems unlikely even under the presence of a strong subsidy scheme.The costs analysis suggests that a remarkable electricity cost reduction or electricity consumption of the HTC stage could be a potential strategy to reach profitability scenarios.Furthermore,significant reduction of green hydrogen production costs is deemed instrumental to improve the economic performance of the process.These results show the formidable techno-economic challenge that our society faces in the path towards circular economy societies.

关键词： Hydrothermal carbonization CO_(2)waste valorization Methanation Profitability analysis

Advancements in synthetic and electrocatalytic exploitation of guest-host intercalated 2D materials

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Progress in Natural Science:Materials International 2024年第3期34卷 454-469页

作者： Qian Yang Kun Wang Meiling Zhang Feihong Du Jiayang Li Chen Zheng Jinyang Li School of chemistry Southwest Jiaotong University Yibin institute of Southwest Jiaotong University

The emergence and development of layered materials have shown great promise for many applications, especially in recent years, the effective modulation of the physicochemical properties of layered materials by intercalation chemistry has led to great potential in material design. In this paper, we review the reaction mechanisms of different guest species(metal atoms/ions, organic molecules/ions, inorganic molecules and inorganic ions)intercalated into the host layered materials as well as the recent progress. It is also reviewed that layered intercalated materials with controllable structure and tunable physicochemical properties can be prepared through the occurrence of interactions between different subjects and guests. The specific applications of intercalation chemistry in the field of electrocatalysis, such as the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction and other electrocatalytic reactions, are then discussed, with emphasis on the mechanism of the improved catalytic activity and stability of the layered materials after guest intercalation.

关键词： Electrocatalysis Guest species Intercalation chemistry Layered materials

Phosphine-Catalyzed [4+3] Annulation Reaction of Indole Derivatives with MBH Carbonates:A Facile Access to Indole-1,2-fused 1,4-Diazepinones and Azepines

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Chinese Journal of chemistry 2024年第3期42卷 271-275页

作者： Yannan Zhu Haoran Jiang Yi-Ning Wang Faculty of chemistry and Chemical Engineering Yancheng Institute of TechnologyYanchengJiangsu224051 China

A phosphine-catalyzed [4+3] annulation between dinucleophilic indole derivatives and Morita−Baylis−Hillman (MBH) carbonates was discovered by using the N1 and N4′/C4′ nucleophilicities of the indole precursors,in which indoles act as four atom synthons. This protocol provides an efficient and facile access to indole-1,2-fused 1,4-diazepinones and azepines in good to high yields in one step,which illustrates potential synthetic utilities in drug discovery.

关键词： Phosphine catalysis [4+3]Annulation Indole derivatives Nitrogen heterocycles Organocatalysis

Pd-catalyzed intermolecular Si–O formation via Si–C activation

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Science China chemistry 2024年第8期67卷 2661-2669页

作者： Shuang Liu Yu-Shu Chen Yichen Wu Peng Wang State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences School of chemistry and Materials Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences College of Material chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Hangzhou Normal University

The development of efficient Si–O bond formation reaction with 100% atom-economy, excellent functional group tolerance, and broad scope under mild conditions is highly desired due to the prevalence of silanol, silyl ether, and their derivatives in synthetic chemistry and materials science. Here, we have realized the Pd-catalyzed Si–O formation reaction via a Si–C activation approach with 100% atom-economy by employing silacyclobutanes(SCBs) and various hydroxy-containing substrates, including water,alcohols, phenols, and silanols. This protocol features a broad substrate scope, remarkable functional compatibility and mild conditions, providing a series of silanols, silyl ethers in high efficiency. Notably, this protocol could also be used for selective protection of hydroxy functionalities, and for the access of a class of novel polymers containing Si–O main chain. Preliminary mechanistic studies unveiled that this reaction underwent a Pd-catalyzed concerted ring-opening mechanism.

关键词： palladium silacyclobutane silanol silyl ether Si–C activation Si–O formation

Mass transfer in heap leaching of weathered crust elution deposited rare earth ore with Al_(2)(SO_(4))_(3) solution

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Journal of Rare Earths 2024年第6期42卷 1175-1181,I0007页

作者： Jingqun Yin Dedong Zeng Jun Tian Yaqing Weng institute of Applied chemistry Jiangxi Academy of SciencesNanchang330096China School of chemistry and Chemical Engineering Nanchang UniversityNanchang330031China

In order to increase efficiency and avoid NH^(4+)-N pollution in the leaching process of weathered crust elution-deposited rare earth ores,the mass transfer in heap leaching with Al_(2)(SO_(4))_(3) solution was simulated with column elution and experimentally optimized.The results indicate that the leaching yield is also up to 99%for leaching with aluminum sulfate instead of ammonium sulfate.The optimal flow rate is 60 mL/h,the height equivalent to a theoretical plate(HETP)is 1.29 mm correspondingly.The peak value position of RE^(3+)is 60 mL/h,Fe^(3+)is 100 mL/h,however,Al^(3+)is 150 mL/h,and the heap leaching process has kinetic separation effect.

关键词： Raree arths Mass transfer Process optimization Heapleaching Weathered crust elution-deposited rare earth ore

Stabilization and detection of labile reaction intermediates in supramolecular containers

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Chinese Chemical Letters 2024年第6期35卷 47-52页

作者： Rui Wang Yang Liang Julius Rebek Jr. Yang Yu Center for Supramolecular chemistry&Catalysis and Department of chemistry College of ScienceShanghai UniversityShanghai 200444China Skaggs institute for Chemical Biology and Department of chemistry The Scripps Research InstituteLa JollaCA 92037United States

Detection and observation of reactive intermediates is an essential step in investigation of reaction pathways.However,most reactive intermediates are unstable and present at low concentrations;their short lifetimes make them difficult to detect and characterize.Supramolecular containers offer opportunities for the stabilization and characterization of those labile species,through isolation from the media and protection inside the cavity of the host.In this review,we summarize the examples of labile reaction intermediates that are stabilized and characterized with the help of supramolecular containers.The container compounds include carcerands,deep cavitands and amide naphthotubes.We focus on unstable guest species-cyclobutadiene,benzocyclopropenone,o-benzyne,1,2,4,6-cycloheptatetraene,anti-Bredt's olefin,fluorophenoxycarbene,O-acylisoamide,and hemiaminalthat act as intermediates in certain organic reactions.

关键词： Supramolecular containers Reaction intermediates Labile species stabilization Short-lived species detection Supramolecular chemistry

Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

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National Science Review 2024年第2期11卷 155-167页

作者： Peng He Meng-Yang Hu Jin-Hong Li Tian-Zhang Qiao Yi-Lin Lu Shou-Fei Zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

The chlorine evolution reaction promoted by organocatalysts with amide functional groups

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Science China chemistry 2024年第3期67卷 749-750页

作者： Lan Zhao Liang-Nian He State Key Laboratory and institute of Elemento-Organic chemistry College of ChemistryNankai UniversityTianjin 300071China

Since the nineteenth century, the chlor-alkali process entails the electrochemical oxidation of sodium chloride solutions to Cl_(2) by the chlorine evolution reaction(CER) and the simultaneous production of sodium hyd... 详细信息

关键词： chlorine hydroxide promoted

Suppressing the lattice oxygen diffusion via high-entropy oxide construction towards stabilized acidic water oxidation

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Nano Research 2024年第3期17卷 1107-1113页

作者： Jing Ni Zhaoping Shi Yibo Wang Jiahao Yang Hongxiang Wu Pengbo Wang Kai Li Meiling Xiao Changpeng Liu Wei Xing State Key Laboratory of Electroanalytic chemistry Jilin Province Key Laboratory of Low Carbon Chemistry PowerChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied chemistry and Engineering University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The scale-up deployment of ruthenium(Ru)-based oxygen evolution reaction(OER)electrocatalysts in proton exchange membrane water electrolysis(PEMWE)is greatly restricted by the poor stability.As the lattice-oxygen-mediated mechanism(LOM)has been identified as the major contributor to the fast performance degradation,impeding lattice oxygen diffusion to inhibit lattice oxygen participation is imperative,yet remains challenging due to the lack of efficient approaches.Herein,we strategically regulate the bonding nature of Ru–O towards suppressed LOM via Ru-based high-entropy oxide(HEO)construction.The lattice disorder in HEOs is believed to increase migration energy barrier of lattice oxygen.As a result,the screened Ti_(23)Nb_(9)Hf_(13)W_(12)Ru_(43)O_(x) exhibits 11.7 times slower lattice oxygen diffusion rate,84%reduction in LOM ratio,and 29 times lifespan extension compared with the state-of-the-art RuO_(2) catalyst.Our work opens up a feasible avenue to constructing stabilized Ru-based OER catalysts towards scalable application.

关键词： ruthenium-based high-entropy oxide suppressing the lattice oxygen diffusion acidic oxygen evolution reaction