Institutional Repository of GuangZhou Institute of Energy Conversion, CAS
Not a member yet
23976 research outputs found
Sort by
Tailoring selectivity in furfural hydrogenolysis over NiCoAl catalyst through a simple rinsing process
No full textIn this study, the structure-activity relationships were investigated in converting biomass-derived furfural into cyclopentanone (CPO) or tetrahydrofuran alcohol (THFA) using a rinsing method to modulate the NiCoAl catalyst. Characterization of two catalysts, NiCoAl (without rinsing) and NiCoAl-R (with rinsing), reveals differences in morphology, composition, and acidity. Rinsing induced a transition from agglomerate to layered structure in NiCoAl-R, which exhibited higher acid strength and improved Lewis to Br & Oslash;nsted acid ratio. NiCoAl-R contained a high percentage of metal oxides, while NiCoAl had a high percentage of metallic species on its surface. These distinctions resulted in varied performance in FFA hydrogenolysis, with NiCoAl-R favoring CPO formation and NiCoAl facilitating THFA production. In situ DRIFTS experiments reveals differing furfural sorption states, and DFT calculations highlighted the higher activity of metal oxides in ring-opening reactions. This investigation elucidates the intricate relationship between catalyst properties and performance, offering insights for tailored catalyst design in biomass conversion
Co-Feeding CO<sub>2</sub> for Methylfuran Aromatization over Bifunctional Zeolite-Supported ZnMoO<sub>4</sub>
No full textAromatization of biofuran offers promising approaches for sustainable biochemical production. However, this process is often hampered by low yields and severe coking on traditional zeolite catalysts. Herein, we report co-feeding CO2 for 2-methylfuran (MF) aromatization (CCMA) over bifunctional ZSM-5 supported ZnMoO4. This bifunctional catalyst can achieve both MF and CO2 conversions of >97 %, generating >85 % carbon yield of target arenes and CO with negligible alkenes (0.05 %). Meanwhile, coke formation is remarkably suppressed from 22.3 % to 8.6 %. ZnMoO4/ZSM-5 is capable of selectively manipulating the reaction intermediates and pathways of the CCMA reactions, favoring the cyclopentenones- and alkenes-based dehydro-aromatization rather than the benzofurans-based pathway. This finding challenges the prevailing understanding that MF aromatization follows a hydrocarbon pool mechanism. Moreover, the abundant surface oxygen vacancies of ZnMoO4 facilitate the adsorption of CO2 and its subsequent reaction with coke. These insights into reaction mechanism and catalyst design for co-conversion of CO2 and biofuran can offer guidelines for process intensification in biomass utilization with a carbon-negative manner
Green aromatic aldehyde production from biomass <i>via</i> catalytic fractionation and ozonolysis
No full textHerein, we propose a catalytic fractionation-ozonolysis strategy for producing aromatic aldehydes from biomass. Native lignin is selectively depolymerized into similar to 30 wt% 4-methoxypropenyl-guaiacol/syringol over MoO2 at 160-180 degrees C, followed by ozonolysis yielding 20 wt% vanillin and syringaldehyde. This strategy is free of base and well preserves carbohydrate pulp
Preparation and thermal performance enhancement of roasted iron tailings based shape-stabilized phase change materials for thermal storage
No full textA new type of shape -stabilized phase change material (SSPCM) was fabricated for thermal energy storage (TES) using a facile synthetic strategy. Lauric acid (LA) was synchronously incorporated into the structural framework of roasted iron tailings (RIT) and graphene nanoparticles (GNP), in which RIT and GNP served as an ideal compatible supporting matrix, meanwhile, GNP was employed as a superior thermal conductivity additive, and LA acted as the working medium. The leakage results of the prepared composites were qualitatively and quantitatively analyzed. The surface morphology, chemical structure, thermal properties, heat transfer efficiency, thermal reliability, and thermal stability of the prepared SSPCMs were examined systematically. The prepared LA/RIT/GNP (5%) SSPCM exhibited relatively excellent thermal performance, which can meet the requirement of the future applications. Particularly, compared to pure LA, the measured thermal conductivity of LA/RIT/GNP (5%) with the addition of GNP was 9.03 times higher. The heat transfer efficiency of SSPCM was augmented by 91.67%. The mechanism of the improvement in thermal performance was revealed by the analysis of the microstructure characteristic parameters. In conclusion, the prepared SSPCM not only has great value in the low -temperature field of TES but also provides a new approach for high -value use of solid waste tailings, which expands the conventional utilization of iron tailings with a high -value approach
Proposal and thermodynamic investigation of pressurized calcium looping integrated with chemical looping combustion for tail-end CO2 capture in a retrofitted natural gas combined cycle power plant
No full textThe integration of tail-end calcium looping into an existing natural gas combined cycle (NGCC) power plant has minimal impact on CO2 capture retrofits. However, a high volume of flue gas needs to be preheated before entering the carbonator, and the relatively high energy consumption of oxygen production exacerbates the energy penalty of the NGCC system with tail-end CO2 capture. This paper proposes the method of pressurized calcium looping integrated with chemical looping combustion (PCaL-CLC). It employs the PCaL-CLC method to reduce the energy penalty and energy consumption of the NGCC system with tail-end CO2 capture. Results show that the proposed system using the PCaL-CLC method achieves a 3.0% reduction in energy penalty, decreasing from 9.1% in the reference system employing the calcium looping method to 6.1% in the proposed system. Besides, the specific energy consumption for CO2 avoided (SPECCA) declines from 4.43 MJLHV/kg CO2 to 2.76 MJLHV/kg CO2. Exergy analysis and energy utilization diagrams reveal the underlying reason for improving system performance. Furthermore, by optimizing the operating parameters of the gas turbine and equipping it with advanced heat recovery steam generation, an energy penalty of 2.9% and a SPECCA of 1.21 MJLHV/kg CO2 are achieved without CO2 compression, which is superior to those of amine scrubbing and hot-end calcium looping CO2 capture technologies. The proposed PCaL-CLC method offers an alternative approach to reducing the energy consumption of tail-end CO2 capture in existing natural gas combined cycle power plants
Open Project of the State Key Laboratory of Marine Resources Utilization in South China Sea[MRUKF2023014]
No full textA novel candidate shape-stabilized phase change material for building energy conservation based on lauric acid/roasted iron tailings-expanded graphite
No full textThis study presents the fabrication of a novel shape-stabilized phase change material (SSPCM) characterized by high thermal capacity and heat transfer efficiency. The material was composed of lauric acid (LA) embedded in roasted iron tailings (RIT) and expanded graphite (EG), utilizing a straightforward, low-cost, and direct impregnation method. The as-prepared LA/RIT-EG SSPCM underwent a comprehensive analysis of leakage tests, surface morphology, chemical compatibility, phase change properties, thermal stability, and reliability. Furthermore, the heat transfer efficiency and thermal conductivity were measured through cooling tests and a laser thermal conductivity analyzer, respectively. The LA/RIT-EG formulation demonstrated an ability to absorb 61.57 wt% LA without leakage, maintaining excellent form-stability with a mass fraction proportion of 29:9.43 for RIT and EG. DSC results revealed phase temperatures and latent heats of 42.49-46.31 degrees C and 108.1-113.1 J/ g, respectively. Compared to pure LA, LA/RIT-EG exhibited a 489.7 % increase in thermal conductivity. Additionally, heat storage and release rates were improved by 81.25 % and 88.24 %, respectively. The study elucidated the mechanism behind the enhancement in encapsulation capacity and thermal conductivity by RIT-EG, validated through specific surface area and wettability tests. Overall, the results suggest that LA/RIT-EG, characterized by high thermal capacity and heat transfer efficiency, holds promise as a potential candidate for thermal energy storage, particularly in the context of energy conservation in buildings
Access Repository Dashboard
Do you manage Institutional Repository of GuangZhou Institute of Energy Conversion, CAS? Access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard!