Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative coo...Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative cooling and solar heating for the uptake of CO_(2) on commercial activated carbons(CACs).During adsorption,the adsorbents are coated with a layer of hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene)[P(VdF-HFP)HP],which cools the adsorbents to a low temperature under sunlight through radiative cooling.For desorption,CACs with broad absorption of the solar spectrum are exposed to light irradiation for heating.The heating and cooling processes are completely driven by solar energy.Adsorption tests under mimicked sunlight using the CACs show that the performance of this system is comparable to that of the traditional ones.Furthermore,under real sunlight irradiation,the adsorption capacity of the CACs can be well maintained after multiple cycles.The present work may inspire the development of new temperature swing procedures with little energy consumption.展开更多
To date,the primary industrial carbon capture approach is still absorption using aqueous solutions of alkanolamines.Here,to pursue a substitute for the amine-based approach to improve the CO_(2) capture efficiency and...To date,the primary industrial carbon capture approach is still absorption using aqueous solutions of alkanolamines.Here,to pursue a substitute for the amine-based approach to improve the CO_(2) capture efficiency and decrease the energy cost further,we report a new carbon capture approach using a 2-methylimidazole(mIm)aqueous solution.The properties and sorption behaviors of this approach have been experimentally investigated.The results show that the mIm solution has higher CO_(2) absorption capacity under relatively higher equilibrium pressure(>130 kPa)and lower desorption heat than the methyldiethanolamine solution.91.6%sorption capacity of mIm solution can be recovered at 353.15 K and 80 kPa.The selectivity for CO_(2)/N_(2) and CO_(2)/CH_(4) can reach an exceptional 7609 and 4324,respectively.Furthermore,the pilot-scale tests were also performed,and the results demonstrate that more than 98%of CO_(2) in the feed gas could be removed and cyclic absorption capacity can reach 1 mol·L^(-1).This work indicates that mIm is an excellent alternative to alkanolamines for carbon capture in the industry.展开更多
Carbon capture,utilization and storage(CCUS) is widely recognized as a vital strategy for mitigating the impact of human induced climate change.Among various CO_(2) adsorbents,intermediate-temperature solid adsorbents...Carbon capture,utilization and storage(CCUS) is widely recognized as a vital strategy for mitigating the impact of human induced climate change.Among various CO_(2) adsorbents,intermediate-temperature solid adsorbents have garnered significant attention due to their potential applications in hydrogen utilization,specifically in the water gas shift,steam reforming and gasification processes.These processes are crucial for achieving carbon neutrality.While laboratory-level studies have showcased the high adsorption capacity of these materials via various synthesis and modification methods,their practical application in complex industrial environments remains challenging,impeding the commercialization process.This review aims to critically summarize the recent research progress made in intermediatetemperature(200-400℃) solid CO_(2) adsorbents,particularly focusing on indicators such as cyclability,gas selectivity,and formability,which play vital roles in industrial application scenarios.Additionally,we provide an overview of laboratory-level advanced technologies specifically tailored for industrial applications.Furthermore,we highlight several industrial-ready advanced technologies that can pave the way for overcoming the challenges associated with large-scale implementation.The insights provided by this review aim to assist researchers in identifying the most relevant research directions for industrial applications.By promoting advances in the application of solid adsorbents,we strive to facilitate the ultimate goal of achieving carbon neutrality.展开更多
Dendritic mesoporous silica nanoparticles own three-dimensional center-radial channels and hierarchical pores,which endows themselves with super-high specific surface area,extremely large pore volumes,especially acces...Dendritic mesoporous silica nanoparticles own three-dimensional center-radial channels and hierarchical pores,which endows themselves with super-high specific surface area,extremely large pore volumes,especially accessible internal spaces,and so forth.Dissimilar guest species(such as organic groups or metal nanoparticles)could be readily decorated onto the interfaces of the channels and pores,realizing the functionalization of dendritic mesoporous silica nanoparticles for targeted applications.As adsorbents and catalysts,dendritic mesoporous silica nanoparticles-based materials have experienced nonignorable development in CO_(2)capture and catalytic conversion.This comprehensive review provides a critical survey on this pregnant subject,summarizing the designed construction of novel dendritic mesoporous silica nanoparticles-based materials,the involved chemical reactions(such as CO_(2)methanation,dry reforming of CH_(4)),the value-added chemicals from CO_(2)(such as cyclic carbonates,2-oxazolidinones,quinazoline-2,4(1H,3H)-diones),and so on.The adsorptive and catalytic performances have been compared with traditional silica mesoporous materials(such as SBA-15 or MCM-41),and the corresponding reaction mechanisms have been thoroughly revealed.It is sincerely expected that the in-depth discussion could give materials scientists certain inspiration to design brand-new dendritic mesoporous silica nanoparticles-based materials with superior capabilities towards CO_(2)capture,utilization,and storage.展开更多
Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and ...Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was conducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were reached.The techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology.展开更多
In this study,an integrated technology is proposed for the absorption and utilization of CO_(2)in alkanolamine solution for the preparation of BaCO_(3)in a high-gravity environment.The effects of absorbent type,high-g...In this study,an integrated technology is proposed for the absorption and utilization of CO_(2)in alkanolamine solution for the preparation of BaCO_(3)in a high-gravity environment.The effects of absorbent type,high-gravity factor,gas/liquid ratio,and initial BaCl2concentration on the absorption rate and amount of CO_(2)and the preparation of BaCO_(3)are investigated.The results reveal that the absorption rate and amount of CO_(2)follow the order of ethyl alkanolamine(MEA)>diethanol amine(DEA)>N-methyldiethanolamine(MDEA),and thus MEA is the most effective absorbent for CO_(2)absorption.The absorption rate and amount of CO_(2)under high gravity are higher than that under normal gravity.Notably,the absorption rate at 75 min under high gravity is approximately 2 times that under normal gravity.This is because the centrifugal force resulting from the high-speed rotation of the packing can greatly increase gas-liquid mass transfer and micromixing.The particle size of BaCO_(3)prepared in the rotating packed bed is in the range of 57.2—89 nm,which is much smaller than that prepared in the bubbling reactor(>100.3 nm),and it also has higher purity(99.6%)and larger specific surface area(14.119 m^(2)·g^(-1)).It is concluded that the high-gravity technology has the potential to increase the absorption and utilization of CO_(2)in alkanolamine solution for the preparation of BaCO_(3).This study provides new insights into carbon emissions reduction and carbon utilization.展开更多
The capture,regeneration,and conversion of CO_(2) from ambient air and flue gas streams are critical aspects of mitigating global warming.Solid sorbents for CO_(2) absorption are very promising as they have high mass ...The capture,regeneration,and conversion of CO_(2) from ambient air and flue gas streams are critical aspects of mitigating global warming.Solid sorbents for CO_(2) absorption are very promising as they have high mass transfer areas without energy input and reduce emissions and minimize corrosion as compared to liquid sorbents.However,precisely tunable solid CO_(2) sorbents are difficult to produce.Here,we demonstrate the high-throughput production of hydrogel-based CO_(2)-absorbing particles via liquid jetting.By wrapping a liquid jet consisting of an aqueous solution of cross-linkable branched polyethylenimine(PEI)with a layer of suspension containing hydrophobic silica nanoparticles,monodisperse droplets with a silica nanoparticle coating layer was formed in the air.A stable Pickering emulsion containing PEI droplets was obtained after these ejected droplets were collected in a heated oil bath.The droplets turn into mm-sized particles after thermal curing in the bath.The diameter,PEI content,and silica content of the particles were systematically varied,and their CO_(2) absorption was measured as a function of time.Steam regeneration of the particles enabled cyclic testing,revealing a CO_(2) absorption capacity of 6.5±0.5 mol kg^(−1)solid PEI in pure CO_(2) environments and 0.7±0.3 mol kg^(−1)solid PEI for direct air capture.Several thousands of particles were produced per second at a rate of around 0.5 kg per hour,with a single nozzle.This process can be further scaled by parallelization.The complete toolbox for the design,fabrication,testing,and regeneration of functional hydrogel particles provides a powerful route toward novel solid sorbents for regenerative CO_(2) capture.展开更多
Carbon nanotubes(CNTs)have garnered significant attention in the fields of science,engineering,and medicine due to their numerous advantages.The initial step towards harnessing the potential of CNTs involves their mac...Carbon nanotubes(CNTs)have garnered significant attention in the fields of science,engineering,and medicine due to their numerous advantages.The initial step towards harnessing the potential of CNTs involves their macroscopic assembly.The present study employed a gentle and direct self-assembly technique,wherein controlled growth of CNT sheaths occurred on the metal wire’s surface,followed by etching of the remaining metal to obtain the hollow tubes composed of CNTs.By controlling the growth time and temperature,it is possible to alter the thickness of the CNTs sheath.After immersing in a solution containing 1 g/L of CNTs at 60℃ for 24 h,the resulting CNTs layer achieved a thickness of up to 60μm.These hollow CNTs tubes with varying inner diameters were prepared through surface reinforcement using polymers and sacrificing metal wires,thereby exhibiting exceptional attributes such as robustness,flexibility,air tightness,and high adsorption capacity that effectively capture CO_(2) from the gas mixture.展开更多
For the application of carbon capture by membrane process,it is crucial to develop a highly permeable CO_(2)-selective membrane.In this work,we reported an ultra-thin polyether-block-amide(Pebax)mixedmatrix membranes(...For the application of carbon capture by membrane process,it is crucial to develop a highly permeable CO_(2)-selective membrane.In this work,we reported an ultra-thin polyether-block-amide(Pebax)mixedmatrix membranes(MMMs)incorporated by graphene oxide(GO),in which the interlayer channels were regulated to optimize the CO_(2)/N_(2) separation performance.Various membrane preparation conditions were systematically investigated on the influence of the membrane structure and separation performance,including the lateral size of GO nanosheets,GO loading,thermal reduction temperature,and time.The results demonstrated that the precisely regulated interlayer channel of GO nanosheets can rapidly provide CO_(2)-selective transport channels due to the synergetic effects of size sieving and preferential adsorption.The GO/Pebax ultra-thin MMMs exhibited CO_(2)/N_(2) selectivity of 72 and CO_(2) permeance of 400 GPU(1 GPU=106 cm^(3)(STP)·cm^(2)·s^(-1)·cmHg^(-1)),providing a promising candidate for CO_(2) capture.展开更多
Our research is centered on the Gandhar oil field, which was discovered in 1983, where daily oil production has declined significantly over the years. The primary objective was to evaluate the feasibility of carbon di...Our research is centered on the Gandhar oil field, which was discovered in 1983, where daily oil production has declined significantly over the years. The primary objective was to evaluate the feasibility of carbon dioxide(CO_(2)) storage through its injection into the siliciclastic reservoirs of Ankleshwar Formation. We aimed to obtain high-resolution acoustic impedance data to estimate porosity employing model-based poststack seismic inversion. We conducted an analysis of the density and effective porosity in the target zone through geostatistical techniques and probabilistic neural networks. Simultaneously, the work also involved geomechanical analysis through the computation of pore pressure and fracture gradient using well-log data, geological information, and drilling events in the Gandhar field. Our investigation unveiled spatial variations in effective porosity within the Hazad Member of the Ankleshwar Formation, with an effective porosity exceeding 25% observed in several areas, which indicates the presence of well-connected pore spaces conducive to efficient CO_(2) migration. Geomechanical analysis showed that the vertical stress(Sv) ranged from 55 MPa to 57 MPa in Telwa and from 63.7 MPa to 67.7 MPa in Hazad Member. The pore pressure profile displayed variations along the stratigraphic sequence, with the shale zone, particularly in the Kanwa Formation, attaining the maximum pressure gradient(approximately 36 MPa). However, consistently low pore pressure values(30-34 MPa) considerably below the fracture gradient curves were observed in Hazad Member due to depletion. The results from our analysis provide valuable insights into shaping future field development strategies and exploration of the feasibility of CO_(2) sequestration in Gandhar Field.展开更多
This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscop...This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscopic simulations of CO_(2)-water-rock system.The work points out the key issues in current research and provides suggestions for future research.After injection of CO_(2) into underground reservoirs,not only conventional pressure-driven flow and mass transfer processes occur,but also special physicochemical phenomena like dissolution,precipitation,and precipitate migration.The coupling of these processes causes complex changes in permeability and porosity parameters of the porous media.Pore-scale microscopic flow simulations can provide detailed information within the three-dimensional pore and throat space and explicitly observe changes in the fluid-solid interfaces of porous media during reactions.At present,the research has limitations in the decoupling of complex mechanisms,characterization of differential multi-mineral reactions,precipitation generation mechanisms and characterization(crystal nucleation and mineral detachment),simulation methods for precipitation-fluid interaction,and coupling mechanisms of multiple physicochemical processes.In future studies,it is essential to innovate experimental methods to decouple“dissolution-precipitation-precipitate migration”processes,improve the accuracy of experimental testing of minerals geochemical reaction-related parameters,build reliable characterization of various precipitation types,establish precipitation-fluid interaction simulation methods,coordinate the boundary conditions of different physicochemical processes,and,finally,achieve coupled flow simulation of“dissolution-precipitation-precipitate migration”within CO_(2)-water-rock systems.展开更多
An integrated vacuum pressure swing adsorption(VPSA) and Rectisol process is proposed for CO_(2) capture from underground coal gasification(UCG) syngas. A ten-bed VPSA process with silica gel adsorbent is firstly desi...An integrated vacuum pressure swing adsorption(VPSA) and Rectisol process is proposed for CO_(2) capture from underground coal gasification(UCG) syngas. A ten-bed VPSA process with silica gel adsorbent is firstly designed to pre-separate and capture 74.57% CO_(2) with a CO_(2) purity of 98.35% from UCG syngas(CH_(4)/CO/CO_(2)/H_(2)/N_(2)= 30.77%/6.15%/44.10%/18.46%/0.52%, mole fraction, from Shaar Lake Mine Field,Xinjiang Province, China) with a feed pressure of 3.5 MPa. Subsequently, the Rectisol process is constructed to furtherly remove and capture the residual CO_(2)remained in light product gas from the VPSA process using cryogenic methanol(233.15 K, 100%(mass)) as absorbent. A final purified gas with CO_(2) concentration lower than 3% and a regenerated CO_(2) product with CO_(2) purity higher than 95% were achieved by using the Rectisol process. Comparisons indicate that the energy consumption is deceased from 2.143 MJ·kg^(-1) of the single Rectisol process to 1.008 MJ·kg^(-1) of the integrated VPSA & Rectisol process, which demonstrated that the deployed VPSA was an energy conservation process for CO_(2) capture from UCG syngas. Additionally, the high-value gas(e.g., CH_(4)) loss can be decreased and the effects of key operating parameters on the process performances were detailed.展开更多
The absorber is the key unit in the post-combustion monoethanolamine(MEA)-based carbon dioxide(CO_(2))capture process.A rate-based dynamic model for the absorber is developed and validated using steady-state experimen...The absorber is the key unit in the post-combustion monoethanolamine(MEA)-based carbon dioxide(CO_(2))capture process.A rate-based dynamic model for the absorber is developed and validated using steady-state experimental data reported in open literature.Sensitivity analysis is performed with respect to important model parameters associated with the reaction,mass transport and phy-sical property relationships.Then,a singular value decomposition(SVD)-based subspace parameter estimation method is proposed to improve the model accu-racy.Finally,dynamic simulations are carried out to investigate the effects of the feed rate of lean MEA solution and the flue inlet conditions.Simulation results indicate that the established dynamic model can reasonably reflect the physical behavior of the absorber.Some new insights are gained from the simulation results.展开更多
基金supported by the National Science Fund for Distinguished Young Scholars(22125804)the National Natural Science Foundation of China(21808110,22078155,and 21878149).
文摘Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative cooling and solar heating for the uptake of CO_(2) on commercial activated carbons(CACs).During adsorption,the adsorbents are coated with a layer of hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene)[P(VdF-HFP)HP],which cools the adsorbents to a low temperature under sunlight through radiative cooling.For desorption,CACs with broad absorption of the solar spectrum are exposed to light irradiation for heating.The heating and cooling processes are completely driven by solar energy.Adsorption tests under mimicked sunlight using the CACs show that the performance of this system is comparable to that of the traditional ones.Furthermore,under real sunlight irradiation,the adsorption capacity of the CACs can be well maintained after multiple cycles.The present work may inspire the development of new temperature swing procedures with little energy consumption.
基金The financial supports received from National Natural Science Foundation of China (U20B6005, 22178378, and 22127812)
文摘To date,the primary industrial carbon capture approach is still absorption using aqueous solutions of alkanolamines.Here,to pursue a substitute for the amine-based approach to improve the CO_(2) capture efficiency and decrease the energy cost further,we report a new carbon capture approach using a 2-methylimidazole(mIm)aqueous solution.The properties and sorption behaviors of this approach have been experimentally investigated.The results show that the mIm solution has higher CO_(2) absorption capacity under relatively higher equilibrium pressure(>130 kPa)and lower desorption heat than the methyldiethanolamine solution.91.6%sorption capacity of mIm solution can be recovered at 353.15 K and 80 kPa.The selectivity for CO_(2)/N_(2) and CO_(2)/CH_(4) can reach an exceptional 7609 and 4324,respectively.Furthermore,the pilot-scale tests were also performed,and the results demonstrate that more than 98%of CO_(2) in the feed gas could be removed and cyclic absorption capacity can reach 1 mol·L^(-1).This work indicates that mIm is an excellent alternative to alkanolamines for carbon capture in the industry.
基金funded by the National Key R&D Program of China(2022YFB4101702)the National Natural Science Foundation of China(52106072 and 52225003)the Fundamental Research Funds for Central Universities(2019JQ03015)。
文摘Carbon capture,utilization and storage(CCUS) is widely recognized as a vital strategy for mitigating the impact of human induced climate change.Among various CO_(2) adsorbents,intermediate-temperature solid adsorbents have garnered significant attention due to their potential applications in hydrogen utilization,specifically in the water gas shift,steam reforming and gasification processes.These processes are crucial for achieving carbon neutrality.While laboratory-level studies have showcased the high adsorption capacity of these materials via various synthesis and modification methods,their practical application in complex industrial environments remains challenging,impeding the commercialization process.This review aims to critically summarize the recent research progress made in intermediatetemperature(200-400℃) solid CO_(2) adsorbents,particularly focusing on indicators such as cyclability,gas selectivity,and formability,which play vital roles in industrial application scenarios.Additionally,we provide an overview of laboratory-level advanced technologies specifically tailored for industrial applications.Furthermore,we highlight several industrial-ready advanced technologies that can pave the way for overcoming the challenges associated with large-scale implementation.The insights provided by this review aim to assist researchers in identifying the most relevant research directions for industrial applications.By promoting advances in the application of solid adsorbents,we strive to facilitate the ultimate goal of achieving carbon neutrality.
基金supported by the National Key R&D program of China(2019YFA0706802)National Natural Science Foundation of China(52063029)+2 种基金Natural Science Basic Research Program of Shaanxi(2022JM-200,2021JQ-716)China Postdoctoral Science Foundation(2020M672269)Doctoral Research Program of Yan’an University(YDBK2019-02)
文摘Dendritic mesoporous silica nanoparticles own three-dimensional center-radial channels and hierarchical pores,which endows themselves with super-high specific surface area,extremely large pore volumes,especially accessible internal spaces,and so forth.Dissimilar guest species(such as organic groups or metal nanoparticles)could be readily decorated onto the interfaces of the channels and pores,realizing the functionalization of dendritic mesoporous silica nanoparticles for targeted applications.As adsorbents and catalysts,dendritic mesoporous silica nanoparticles-based materials have experienced nonignorable development in CO_(2)capture and catalytic conversion.This comprehensive review provides a critical survey on this pregnant subject,summarizing the designed construction of novel dendritic mesoporous silica nanoparticles-based materials,the involved chemical reactions(such as CO_(2)methanation,dry reforming of CH_(4)),the value-added chemicals from CO_(2)(such as cyclic carbonates,2-oxazolidinones,quinazoline-2,4(1H,3H)-diones),and so on.The adsorptive and catalytic performances have been compared with traditional silica mesoporous materials(such as SBA-15 or MCM-41),and the corresponding reaction mechanisms have been thoroughly revealed.It is sincerely expected that the in-depth discussion could give materials scientists certain inspiration to design brand-new dendritic mesoporous silica nanoparticles-based materials with superior capabilities towards CO_(2)capture,utilization,and storage.
文摘Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was conducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were reached.The techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology.
基金supported by Research Project Supported by Horizon Europe Framework Programme(101183092)Shanxi Scholarship Council of China(2023-128)+2 种基金National Natural Science Foundation of China(22208328)Fundamental Research Program of Shanxi Province(20210302124618)Small and mediumsized oriented scientific and technological enterprises innovation ability improvement project of Shandong Province(2023TSGC0004)。
文摘In this study,an integrated technology is proposed for the absorption and utilization of CO_(2)in alkanolamine solution for the preparation of BaCO_(3)in a high-gravity environment.The effects of absorbent type,high-gravity factor,gas/liquid ratio,and initial BaCl2concentration on the absorption rate and amount of CO_(2)and the preparation of BaCO_(3)are investigated.The results reveal that the absorption rate and amount of CO_(2)follow the order of ethyl alkanolamine(MEA)>diethanol amine(DEA)>N-methyldiethanolamine(MDEA),and thus MEA is the most effective absorbent for CO_(2)absorption.The absorption rate and amount of CO_(2)under high gravity are higher than that under normal gravity.Notably,the absorption rate at 75 min under high gravity is approximately 2 times that under normal gravity.This is because the centrifugal force resulting from the high-speed rotation of the packing can greatly increase gas-liquid mass transfer and micromixing.The particle size of BaCO_(3)prepared in the rotating packed bed is in the range of 57.2—89 nm,which is much smaller than that prepared in the bubbling reactor(>100.3 nm),and it also has higher purity(99.6%)and larger specific surface area(14.119 m^(2)·g^(-1)).It is concluded that the high-gravity technology has the potential to increase the absorption and utilization of CO_(2)in alkanolamine solution for the preparation of BaCO_(3).This study provides new insights into carbon emissions reduction and carbon utilization.
基金supported by the European Regional Development Fund(CONTROL,EFRO#00943).
文摘The capture,regeneration,and conversion of CO_(2) from ambient air and flue gas streams are critical aspects of mitigating global warming.Solid sorbents for CO_(2) absorption are very promising as they have high mass transfer areas without energy input and reduce emissions and minimize corrosion as compared to liquid sorbents.However,precisely tunable solid CO_(2) sorbents are difficult to produce.Here,we demonstrate the high-throughput production of hydrogel-based CO_(2)-absorbing particles via liquid jetting.By wrapping a liquid jet consisting of an aqueous solution of cross-linkable branched polyethylenimine(PEI)with a layer of suspension containing hydrophobic silica nanoparticles,monodisperse droplets with a silica nanoparticle coating layer was formed in the air.A stable Pickering emulsion containing PEI droplets was obtained after these ejected droplets were collected in a heated oil bath.The droplets turn into mm-sized particles after thermal curing in the bath.The diameter,PEI content,and silica content of the particles were systematically varied,and their CO_(2) absorption was measured as a function of time.Steam regeneration of the particles enabled cyclic testing,revealing a CO_(2) absorption capacity of 6.5±0.5 mol kg^(−1)solid PEI in pure CO_(2) environments and 0.7±0.3 mol kg^(−1)solid PEI for direct air capture.Several thousands of particles were produced per second at a rate of around 0.5 kg per hour,with a single nozzle.This process can be further scaled by parallelization.The complete toolbox for the design,fabrication,testing,and regeneration of functional hydrogel particles provides a powerful route toward novel solid sorbents for regenerative CO_(2) capture.
基金Project(ZCLTGS24B0101)supported by Zhejiang Provincial Natural Science Foundation of ChinaProject(Y202250501)supported by Scientific Research Fund of Zhejiang Provincial Education Department,ChinaProject supported by SRT Research Project of Jiaxing Nanhu University,China。
文摘Carbon nanotubes(CNTs)have garnered significant attention in the fields of science,engineering,and medicine due to their numerous advantages.The initial step towards harnessing the potential of CNTs involves their macroscopic assembly.The present study employed a gentle and direct self-assembly technique,wherein controlled growth of CNT sheaths occurred on the metal wire’s surface,followed by etching of the remaining metal to obtain the hollow tubes composed of CNTs.By controlling the growth time and temperature,it is possible to alter the thickness of the CNTs sheath.After immersing in a solution containing 1 g/L of CNTs at 60℃ for 24 h,the resulting CNTs layer achieved a thickness of up to 60μm.These hollow CNTs tubes with varying inner diameters were prepared through surface reinforcement using polymers and sacrificing metal wires,thereby exhibiting exceptional attributes such as robustness,flexibility,air tightness,and high adsorption capacity that effectively capture CO_(2) from the gas mixture.
基金financially supported by The Natural Science Foundation of the Jiangsu Higher Education Institutions of China(22KJB530007,22KJA530001)National Natural Science Foundation of China(22208151)+1 种基金the Natural Science Foundation of Jiangsu Province(BK20220002)the State Key Laboratory of MaterialsOriented Chemical Engineering(SKL-MCE-22B07).
文摘For the application of carbon capture by membrane process,it is crucial to develop a highly permeable CO_(2)-selective membrane.In this work,we reported an ultra-thin polyether-block-amide(Pebax)mixedmatrix membranes(MMMs)incorporated by graphene oxide(GO),in which the interlayer channels were regulated to optimize the CO_(2)/N_(2) separation performance.Various membrane preparation conditions were systematically investigated on the influence of the membrane structure and separation performance,including the lateral size of GO nanosheets,GO loading,thermal reduction temperature,and time.The results demonstrated that the precisely regulated interlayer channel of GO nanosheets can rapidly provide CO_(2)-selective transport channels due to the synergetic effects of size sieving and preferential adsorption.The GO/Pebax ultra-thin MMMs exhibited CO_(2)/N_(2) selectivity of 72 and CO_(2) permeance of 400 GPU(1 GPU=106 cm^(3)(STP)·cm^(2)·s^(-1)·cmHg^(-1)),providing a promising candidate for CO_(2) capture.
基金Supported by DST,Ministry of Science and Technology(Reference:DST/TMD/CCUS/Co E/2020/IITB (C))。
文摘Our research is centered on the Gandhar oil field, which was discovered in 1983, where daily oil production has declined significantly over the years. The primary objective was to evaluate the feasibility of carbon dioxide(CO_(2)) storage through its injection into the siliciclastic reservoirs of Ankleshwar Formation. We aimed to obtain high-resolution acoustic impedance data to estimate porosity employing model-based poststack seismic inversion. We conducted an analysis of the density and effective porosity in the target zone through geostatistical techniques and probabilistic neural networks. Simultaneously, the work also involved geomechanical analysis through the computation of pore pressure and fracture gradient using well-log data, geological information, and drilling events in the Gandhar field. Our investigation unveiled spatial variations in effective porosity within the Hazad Member of the Ankleshwar Formation, with an effective porosity exceeding 25% observed in several areas, which indicates the presence of well-connected pore spaces conducive to efficient CO_(2) migration. Geomechanical analysis showed that the vertical stress(Sv) ranged from 55 MPa to 57 MPa in Telwa and from 63.7 MPa to 67.7 MPa in Hazad Member. The pore pressure profile displayed variations along the stratigraphic sequence, with the shale zone, particularly in the Kanwa Formation, attaining the maximum pressure gradient(approximately 36 MPa). However, consistently low pore pressure values(30-34 MPa) considerably below the fracture gradient curves were observed in Hazad Member due to depletion. The results from our analysis provide valuable insights into shaping future field development strategies and exploration of the feasibility of CO_(2) sequestration in Gandhar Field.
基金Supported by the National Natural Science Foundation of China(52234003,52222402,52304044).
文摘This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscopic simulations of CO_(2)-water-rock system.The work points out the key issues in current research and provides suggestions for future research.After injection of CO_(2) into underground reservoirs,not only conventional pressure-driven flow and mass transfer processes occur,but also special physicochemical phenomena like dissolution,precipitation,and precipitate migration.The coupling of these processes causes complex changes in permeability and porosity parameters of the porous media.Pore-scale microscopic flow simulations can provide detailed information within the three-dimensional pore and throat space and explicitly observe changes in the fluid-solid interfaces of porous media during reactions.At present,the research has limitations in the decoupling of complex mechanisms,characterization of differential multi-mineral reactions,precipitation generation mechanisms and characterization(crystal nucleation and mineral detachment),simulation methods for precipitation-fluid interaction,and coupling mechanisms of multiple physicochemical processes.In future studies,it is essential to innovate experimental methods to decouple“dissolution-precipitation-precipitate migration”processes,improve the accuracy of experimental testing of minerals geochemical reaction-related parameters,build reliable characterization of various precipitation types,establish precipitation-fluid interaction simulation methods,coordinate the boundary conditions of different physicochemical processes,and,finally,achieve coupled flow simulation of“dissolution-precipitation-precipitate migration”within CO_(2)-water-rock systems.
基金financially supported by the Renewable Energy and Hydrogen Projects in National Key Research & Development Program of China (2019YFB1505000)。
文摘An integrated vacuum pressure swing adsorption(VPSA) and Rectisol process is proposed for CO_(2) capture from underground coal gasification(UCG) syngas. A ten-bed VPSA process with silica gel adsorbent is firstly designed to pre-separate and capture 74.57% CO_(2) with a CO_(2) purity of 98.35% from UCG syngas(CH_(4)/CO/CO_(2)/H_(2)/N_(2)= 30.77%/6.15%/44.10%/18.46%/0.52%, mole fraction, from Shaar Lake Mine Field,Xinjiang Province, China) with a feed pressure of 3.5 MPa. Subsequently, the Rectisol process is constructed to furtherly remove and capture the residual CO_(2)remained in light product gas from the VPSA process using cryogenic methanol(233.15 K, 100%(mass)) as absorbent. A final purified gas with CO_(2) concentration lower than 3% and a regenerated CO_(2) product with CO_(2) purity higher than 95% were achieved by using the Rectisol process. Comparisons indicate that the energy consumption is deceased from 2.143 MJ·kg^(-1) of the single Rectisol process to 1.008 MJ·kg^(-1) of the integrated VPSA & Rectisol process, which demonstrated that the deployed VPSA was an energy conservation process for CO_(2) capture from UCG syngas. Additionally, the high-value gas(e.g., CH_(4)) loss can be decreased and the effects of key operating parameters on the process performances were detailed.
基金The work was financially supported by Basic Public Welfare research Plan of Zhejiang Province(LGG19F030006)Key Laboratory of Intelligent Manufacturing Quality Big Data Tracing and Analysis of Zhejiang Province,China Jiliang University(Grant No.ZNZZSZ–CJLU2022–04)the Key Research and Development Program of Ningbo(2022Z165).
文摘The absorber is the key unit in the post-combustion monoethanolamine(MEA)-based carbon dioxide(CO_(2))capture process.A rate-based dynamic model for the absorber is developed and validated using steady-state experimental data reported in open literature.Sensitivity analysis is performed with respect to important model parameters associated with the reaction,mass transport and phy-sical property relationships.Then,a singular value decomposition(SVD)-based subspace parameter estimation method is proposed to improve the model accu-racy.Finally,dynamic simulations are carried out to investigate the effects of the feed rate of lean MEA solution and the flue inlet conditions.Simulation results indicate that the established dynamic model can reasonably reflect the physical behavior of the absorber.Some new insights are gained from the simulation results.