功能化离子液体在二氧化碳吸收分离中的应用

吸收及分离二氧化碳是降低碳排放和应对全球气候变化的主要策略之一,这就必然要求全球科技工作者注重开发具有选择性高效吸收分离二氧化碳的新材料和新路线。作为近20多年来发展的一类代表性的新材料,离子液体（尤其是功能化离子液体）具有独特的物理化学性质,例如几乎没有蒸气压、液态温度范围大、热稳定性和化学稳定性好、电化学窗口宽、不可燃、结构-性质可调控等。这些性质使离子液体在二氧化碳吸收及分离领域受到广泛关注。重点综述了近5年（2015~2019）来功能化离子液体吸收分离二氧化碳的研究进展, 主要内容包括单位点离子液体、多位点离子液体、基于功能化离子液体的混合物、功能化离子液体杂化材料对二氧化碳的吸收分离。同时, 对目前该领域的发展所面临的主要问题和进一步的研究工作进行了分析讨论。     

Application of membrane separation technology in postcombustion carbon dioxide capture process

Membrane separation technology is a possible breakthrough in post-combustion carbon dioxide capture process. This review first focuses on the requirements for CO₂ separation membrane, and then outlines the existing competitive materials, promising preparation methods and processes to achieve desirable CO₂ selectivity and permeability. A particular emphasis is addressed on polyimides, poly (ethylene oxide), mixed-matrix membrane, thermally-rearranged polymer, fixed site carrier membrane, ionic liquid membrane and electrodialysis process. The advantages and drawbacks of each of materials and methods are discussed. Research threads and methodology of CO₂ separation membrane and the key issue in this area are concluded     

变压吸附分离工业废气二氧化碳的研究进展

概述了未来人类对过量二氧化碳排放的处理办法,即碳的捕获和存储(CCS).简介了4种二氧化碳的分离工艺及特点和工业中二氧化碳的捕获系统.阐述了变压吸附工艺的基本原理和其在捕获工业废气中二氧化碳上的应用,以及变压吸附分离二氧化碳的工艺在循环结构设计、吸附剂材料和数值模拟等方面的研究进展和国内外的工业化应用.分析了目前该工艺仍存在的问题,指出该技术具有广阔的应用前景.     

胆碱类低共融溶剂在CO2捕集与分离中的应用

胆碱类低共融溶剂是一种新型的离子液体。它不仅具有传统离子液体的优点,还具有价格低廉、低毒、生物可降解等优势。对胆碱类低共融溶剂在CO₂捕集与分离中所涉及的物理性质,如气体的溶解度、CO₂的吸收-解吸、密度、稳定性、黏度和表面张力等进行考察,并分析了胆碱类低共融溶剂的结构对各物性的影响。通过与传统离子液体的对比,胆碱类低共融溶剂在CO₂捕集与分离中的应用具有一定的优势,如CO₂溶解度高,黏度低。然而,胆碱类低共融溶剂在气体的选择性分离、表面张力等的研究还不足,且热稳定性方面还存在瓶颈,因此,其在CO₂捕集和分离中的应用还有待进一步探讨。     

二氧化碳直接空气捕集材料与技术研究进展

直接空气捕集（DAC）等新兴负碳排放技术是实现“双碳”目标的托底技术保障,近年来受到广泛关注。本文简要分析了直接空气碳捕集技术的特性,归纳总结了胺功能化无机材料和聚合物、金属氢氧化物和碳酸盐、多孔材料等痕量二氧化碳捕集性能,初步分析了负载方式、载体结构等与吸附容量和动力学的关系。浅析了该领域发展面临的问题和机遇,从能耗和性能方面对捕集材料和技术的研发提出以下建议：相较于物理吸附材料,胺功能化材料和固体碱等化学吸附材料具有更好的应用前景;在工艺开发领域,可以借鉴其他低浓度气体深度脱除工艺的经验;另一方面,可以结合不同工艺优势,设计多种工艺耦合的流程;最后,在严峻的环境问题下,必须加快材料研发的步伐,未来的研究重点应集中在材料的设计和低能耗再生方式的开发上。     

笼型水合物膜分离和捕获二氧化碳研究进展

开发一种低碳、高效的分离和捕获二氧化碳方法一直是缓解温室效应的关键技术。本文首先比较了现有的5种碳捕获技术,发现相较于化学吸收、深冷分离和变压吸附,水合物法和膜分离技术具有绿色环保、操作简单的优势。随后,本文以水合物法为切入点,阐述了其分离机理和强化手段。为进一步研究更加有效的新技术,通过利用水合物法的技术优势,结合膜分离的结构,提出一种更加具有发展潜力的水合物膜分离技术。然后,根据水合物膜的成膜方式将水合物膜技术分为第一、二、三代,并重点分析了每代水合物膜技术的改进手段。最后指出未来第三代水合物膜分离技术应从以下3个方面寻求突破与创新:探索合适膜载体材料;寻找合适的添加剂;优化温度、压力、流速水合分离条件。     

离子液体中二氧化碳的溶解度研究进展

室温离子液体具有独特的气体选择溶解性,在二氧化碳(CO2)的捕集和分离中有很好的应用前景。综述了近年来CO2在不同离子液体中的溶解度研究进展,比较了CO2在常规离子液体和功能型离子液体中的不同溶解机制,分析、归纳了向离子液体中引入不同官能团对CO2溶解性能的影响规律,指出了离子液体捕集CO2的未来研究方向。     

Nitric oxide and carbon monoxide permeation through glassy polymeric membranes for carbon dioxide separation

Minor components present in polymeric membrane gas separation can have a significant influence on the separation performance. Carbon monoxide and nitric oxide exist in post-combustion gas streams and can therefore influence CO₂ transport through membranes designed for that application. Here, the permeability of nitric oxide (NO) through three glassy polymeric membranes (polysulfone, Matrimid 5218 and 6FDA-TMPDA) was determined and found to be less than the CO₂ but greater than the N₂ permeability in each membrane. This study also investigated the influence of 1000 ppm CO on the mixed gas permeability of CO₂ and N₂ for two glassy polymeric membranes; polysulfone and 6FDA-TMPDA. For both membranes, CO competitive sorption resulted in a reduction in the measured permeability of CO₂ and N₂ even though present at only low concentration.     

气体膜分离混合气中二氧化碳的研究进展

气体膜分离技术作为碳捕获方案被国际社会认为是最有发展潜力的脱碳方法之一.综述介绍了中空纤维膜接触器、膜结构、系统工艺和吸收剂的研究现状.相对于水和碳酸盐类,醇胺具有的二氧化碳吸收率高、反应热低、反应速度快以及容易再生等优点,在研究与工业过程中是应用最广泛的吸收剂之一.     

A hybrid equation of state and Kent-Eisenberg model for accurate prediction of carbon dioxide separation by aqueous alkanolamines

A hybrid predictive model has been developed for accurate prediction of thermodynamics of carbon dioxide separation by aqueous alkanolamines. The model incorporates equation of state/excess Gibbs energy model into Kent–Eisenberg approach to predict carbon dioxide–alkanolamine–water equilibria. The approach imparts theoretical corrections to Kent–Eisenberg approach and significantly extends their range of application for monoethanolamine, diethanolamine, methyldiethanolamine, and 2-amino-2-methyl-1-propanol solutions. The proposed model suitably predicts thermodynamics of carbon dioxide separation, well beyond the regressed range of parameters. The results are in excellent agreement with experimental data for a wide range of process parameters and found superior to existing thermodynamic approaches.     

燃煤电厂烟气二氧化碳胺法捕集工艺改进研究进展

有机胺化学吸收法是当前最具大规模工业化应用前景的燃煤电厂烟气二氧化碳捕集技术,但目前仍存在能耗较高的缺点,而通过工艺改进将是降低碳捕集系统能耗的有效方法之一。本文从吸收端和解吸端分别对十余类工艺改进方法的原理和研究进展进行了阐述,其中吸收端涉及吸收塔内部冷却、富液循环、贫液分配流和旋转塔4类工艺;解吸端则包括解吸塔塔级再热、富液分流、闪蒸再生、闪蒸压缩、多压力解吸、多效解吸塔和直接蒸汽解吸共7类工艺。分析表明,富液分流、闪蒸压缩、多效解吸塔和直接蒸汽解吸工艺展示了较好的改进效果。并进一步介绍了多种工艺联合改进的碳捕集系统综合优化方法,特别对综合优化过程中需要重点关注的各工艺间相互作用以及吸收剂与优化工艺匹配性进行了讨论说明,由此指出联合采用新型胺吸收剂和复合工艺改进是未来开发先进胺法碳捕集系统的重要研究方向。     

Recent developments on carbon capture and storage: An overview

The Intergovernmental Panel on Climate Change assumes the warming of the climate system, associating the increase of global average temperature to the observed increase of the anthropogenic greenhouse gas (GHG) concentrations in the atmosphere. Carbon dioxide (CO₂) is considered the most important GHG, due to the dependence of world economies on fossil fuels, since their combustion processes are the most important sources of this gas. CO₂ concentrations are increasing in the last decades mainly due to the increase of anthropogenic emissions. The processes involving CO₂ capture and storage is gaining attention on the scientific community as an alternative for decreasing CO₂ emission, reducing its concentration in ambient air. However, several technological, economical and environmental issues as well as safety problems remain to be solved, such as the following needs: increase of CO₂ capture efficiency, reduction of process costs, and verification of environmental sustainability of CO₂ storage. This paper aims to review the recent developments (from 2006 until now) on the carbon capture and storage (CCS) methodologies. Special attention was focused on the basic findings achieved in CCS operational projects.     

Capture of carbon dioxide by an ion-exchange resin: Influence of gas humidity on capture mechanisms

This paper evaluates moisture content effects on CO₂ capture of an ion-exchange resin (IER) functionalised with a primary amine group. IER capacities were determined by breakthrough with an inlet gas containing 10 vol% CO₂, nitrogen and various moisture contents. Three types of behaviour were identified according to humidity level. In saturated air conditions, the stoichiometry could be justified by carbonates and bicarbonates fixation. In dry conditions, we suspect a joint physical adsorption and reaction mechanism. For intermediate humidity, the stoichiometry of 1 CO₂ for 1 amine group is consistent with a bicarbonate fixation or carbamic acid formation.     

燃烧后二氧化碳捕集技术与应用进展

二氧化碳是主要的温室气体之一，其大量排放已对全球的气候环境造成严重影响，迫切需要开发经济有效的碳捕集技术。目前，碳捕集技术主要有吸收分离法、吸附分离法、膜分离法和低温分离法。首先，介绍了碳捕集技术的发展现状、应用研究进展和未来发展趋势；总结了国内外碳捕集示范项目；重点对比了各碳捕集技术的优势与缺点，同时强调了捕集技术面临的困难与挑战；指出目前主要的碳捕集技术均难以独立实现高效、节能、经济的碳捕集分离，需针对不同的应用场景，选择适合的分离技术，并提出了适用分离场景的应用建议；最后，简要介绍了混合捕集技术的研究成果，提出混合捕集技术可能是一种突破单一捕集技术瓶颈的可行方法。     

Chemical functionalization strategies for carbon dioxide capture in microporous organic polymers

We review the design and use of microporous polymers for pre‐ and post‐combustion capture of CO₂. Microporous organic polymers are promising candidates for CO₂ capture materials. They have good physicochemical stabilities and high surface areas. Ultrahigh‐surface‐area microporous organic polymers could find use in pre‐combustion capture, while networks with lower surface areas but higher heats of sorption for CO₂ might be more relevant for lower pressure, post‐combustion capture. We discuss strategies for enhancing CO₂ uptakes including increasing surface area, chemical functionalization to provide high‐enthalpy binding sites and the potential for pore size tuning. © 2013 Society of Chemical Industry     

Stable benzimidazole-incorporated porous polymer network for carbon capture with high efficiency and low cost

Porous Polymer Networks (PPNs) are an emerging category of advanced porous materials that are of interest for carbon dioxide capture due to their great stabilities and convenient functionalization processes. In this work, an intrinsically-functionalized porous network, PPN-101, was prepared from commercially accessible materials via an easy two-step synthesis. It has a BET surface area of 1095 m²/g. Due to the presence of the benzimidazole units in the framework, its CO₂ uptake at 273 K reaches 115 cm³/g and its calculated CO₂/N₂ selectivity is 199, which indicates its potential for CO₂/N₂ separation. The great stability, large CO₂/N₂ selectivity and low production cost make PPN-101 a promising material for industrial separation of CO₂ from flue gas. Its H₂ and CH₄ uptake properties were also investigated.     

Gas hydrate formation from hydrogen/carbon dioxide and nitrogen/carbon dioxide gas mixtures

Gas hydrates from CO₂/N₂ and CO₂/H₂ gas mixtures were formed in a semi-batch stirred vessel at constant pressure and temperature of 273.7 K. These mixtures are of interest to CO₂ separation and recovery from flue gas and fuel gas, respectively. During hydrate formation the gas uptake was determined and the composition changes in the gas phase were obtained by gas chromatography. The rate of hydrate growth from CO₂/H₂ mixtures was found to be the fastest. In both mixtures CO₂ was found to be preferentially incorporated into the hydrate phase. The observed fractionation effect is desirable and provides the basis for CO₂ capture from flue gas or fuel gas mixtures. The separation from fuel gas is also a source of H₂. The impact of tetrahydrofuran (THF) on hydrate formation from the CO₂/N₂ mixture was also observed. THF is known to substantially reduce the equilibrium formation conditions enabling hydrate formation at much lower pressures. THF was found to reduce the induction time and the rate of hydrate growth.     

基于热流逸效应的燃煤电厂烟气二氧化碳分离系统

分离捕集CO₂是实现“双碳”目标的重要途径之一。常规的CO₂分离方法普遍能耗较高,若能以余(废)热为动力来分离CO₂则可综合利用能源、降低能耗。本文针对高碳排放但却拥有丰富余(废)热资源的燃煤电厂,提出了一种基于热流逸效应的烟气CO₂分离系统,并建立了相应的分离过程数学模型和系统性能评价指标。分析表明,CO₂的浓度和回收率均随热流逸式气体分离器串联级数的增加而升高,但浓度和回收率达到某一阈值后效果不再明显;典型的1000MW燃煤电厂烟气经该系统中串联的24级分离器处理后,CO₂的物质的量分数最高可达98.89%,回收率达72.53%。此外,该系统可梯级利用烟气的余热,?效率为64.8%,单位能耗为0.047GJ/tCO₂,与传统CO₂分离方法相比具有一定节能潜力。利用热流逸效应分离CO₂符合当下净零碳排放的政策导向,为CO₂的分离捕集提供了新思路。     

State of the art of ionic liquid-modified adsorbents for CO2 capture and separation

The enormous emission of carbon dioxide (CO₂) from industries has triggered a series of environmental issues. In recent years, ionic liquids (ILs) as novel absorbents are widely used for CO₂ capture owing to their low vapor pressure and tunable structures. IL-modified adsorbents have the advantages of both ILs and porous supports, such as high CO₂ selectivity and high specific surface area, which are novel agents to capture CO₂ with broad application prospects. In this review, more than 140 IL-modified adsorbents for CO₂ capture in recent years were systematically summarized. The types of ILs including conventional ILs and functionalized ILs on CO₂ separation performance of different IL hybrid adsorbents, and their adsorption mechanisms were also discussed. Finally, future perspectives on IL-modified adsorbents for CO₂ separation were further posed.     

为强化石油回采捕集CO2的全周期评估

The development and deployment of Carbon dioxide Capture and Storage （CCS） technology is a cornerstone of the Norwegian government＇s climate strategy. A number of projects are currently evaluated/planned along the Norwegian West Coast, one at Tjeldbergodden. COe from this project will be utilized in part for enhanced oil recovery in the Halten oil field, in the Norwegian Sea. We study a potential design of such a system. A combined cycle power plant with a gross power output of 832 MW is combined with CO2 capture plant based on a post-combustion capture using amines as a solvent. The captured CO2 is used for enhanced oil recovery （EOR）. We employ a hybrid life-cycle assessment （LCA） method to assess the environmental impacts of the system. The study focuses on the modifications and operations of the platform during EOR. We allocate the impacts connected to the capture of CO2 to electricity production, and the impacts connected to the transport and storage of CO2 to the oil produced. Our study shows a substantial reduction of the greenhouse gas emissions from power production by 80% to 75 g·（kW·h）^-1. It also indicates a reduction of the emissions associated with oil production per unit oil produced, mostly due to the increased oil production. Reductions are especially significant if the additional power demand due to EOR leads to power supply from the land.