Advances in CO2 capture technology: A patent review
Graphical abstract
Highlights
► Timely updates on carbon capture technologies: More than 1000 patents on solvent, sorbent, and membrane. ► More patents on solvent and sorbent compared to membrane. ► Environmental and health concerns exist regarding carbon capture technologies.
Introduction
With the rapid development of modern civilization, carbon dioxide (CO2) is produced in large quantities in industry, for instance, by the combustion of coal, coke, and natural gas, in the fermentation of carbohydrate materials and sugars, in the manufacture of cement and lime, and etc. Indeed, more than 30 billion tons of CO2 are added to the atmosphere each year. However, the emission of CO2, one of the major greenhouse gases, has raised great concerns about the relationship between anthropogenic CO2 and global warming; the emission of CO2 may have contributed to urban smog, acid rain, and health problems [1], [2]. In another scenario (e.g., a space capsule, a submarine, a subterranean mining environment, or a closed-circuit respiratory apparatus), CO2 produced by the occupants of a closed ecological system must be removed from air. Therefore, CO2 removal is of importance. As a result, a variety of methods have been studied and patented for the removal and separation of CO2 from industrial waste and mine gases, from the air, and from gases produced by animal metabolism, such as human respiration.
Many technical challenges, however, are facing potential large-scale implementation of CO2 capture in power plants [3]. Fig. 1 presents the simplified pathways of CO2 production, capture or separation, and storage or re-utilization. Among them, CO2 capture is the key step economically and has two technology routes: (1) pre-combustion: capture from the reformed synthesis gas of an upstream gasification unit; and (2) post-combustion: capture CO2 from the flue gas stream after combustion. Upon capture, CO2 can be stored underground, used for enhancing oil recovery, and as carbon resources to be converted into other useful compounds [4], [5] (Fig. 1). The current technologies for CO2 capture and separation mainly include solvent, sorbent, and membrane, and the mechanisms for CO2 capture depend on the chemistry of the capturing approaches or materials. For instance, in the monoethanolamine (MEA) approach, CO2 is captured based on its interaction with amines to form bicarbonates or carbamates.
During the past few decades, much effort has been devoted to developing new technologies for CO2 capture, storage, and utilization. Many reviews on this topic are already published in the literature [3], [4], [5], [6], [7]. However, to our knowledge, there is no report on patented innovations on CO2 capture technology. In order to address the importance of patented innovations, in this article, the current status of patents on CO2 capture is reviewed. It is noteworthy to mention that clean energy technologies (e.g. solar, wind, nuclear, and proton exchange membrane fuel cell, and hydrogen-based power generation) that can lower CO2 emission are not discussed here but are very important.
Section snippets
Method for carbon capture patent search
In this study, the Espacenet website (http://www.epo.org/searching/free/espacenet.html) [8] was used to search for patents; Espacenet is the most comprehensive patent database available. Espacenet collects published patent applications from 1836 to today and from more than 80 countries with more than 70 million patent documents.
Accessing the Espacenet website, an advanced search using keywords in patent titles and abstracts was carried out. A search for CO2 capture sorbent patents was conducted
Carbon capture patents
A total of 1297 patents on CO2 capture solid sorbents, solvents, or membranes were found. Among them, approximately 37.5% (486 patents) belonged to solvent, 35.5% (461 patents) and 27.0% (350 patents) belonged to solid sorbent and membrane, respectively (Fig. 2). The likely reason that there were more patents on solvent and solid sorbents was because more types of materials can be used as solvent or solid sorbents. For instance, ethanolamines, ammonia, alkali metal solutions (e.g., alkali metal
Environmental and health concerns
Overall, the impact of CO2 capture technologies on the environment and health is not well studied and comparative investigations are needed. Carbon capture sorbents, solvents, and membranes may have an unpleasant or detrimental effect on the environment and/or human health. For instance, it has long been known that the dust of certain carbon capture sorbents is harmful. Dust from sorbents such as lime and alkaline compounds can be produced during their manufacture, handling, and storage; the
Perspective and conclusions
Carbon dioxide is an inert gas that has no heating value of combustion and it is an environmental concern since it is the major greenhouse gas. Varied technologies have been developed for CO2 capture and separation. Each technology has its strengths and limitations. For instance, Table 1, Table 2 summarize the advantages and limitations of solvent, sorbent, and membrane as pre- and post-combustion technologies. However, there are currently no practical processes for removing CO2 from large CO2
Acknowledgements
As part of the National Energy Technology Laboratory’s Regional University Alliance (NETL-RUA), a collaborative initiative of the NETL, this technical effort was performed under the RES contract DE-FE0004000. Support was also received from WV NASA EPSCoR. Any opinions, findings, conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the funding agencies or their institutions. The authors thank George A. Richards and Henry W.
References (124)
Global challenges and strategies for control, conversion and utilization of CO2 for sustainable development involving energy, catalysis, adsorption and chemical processing
Catal Today
(2006)- et al.
The outlook for improved carbon capture technology
Progr Energy Combust Sci
(2012) - et al.
PVTxy properties of CO2 mixtures relevant for CO2 capture, transport and storage: review of available experimental data and theoretical models
Appl Energy
(2011) - et al.
Performance of amine-multilayered solid sorbents for CO2 removal: effect of fabrication variables
Int J Greenhouse Gas Control
(2011) - et al.
CO2 capture performance of calcium-based sorbent doped with manganese salts during calcium looping cycle
Appl Energy
(2012) - et al.
Incorporating IGCC and CaO sorption-enhanced process for power generation with CO2 capture
Appl Energy
(2012) - et al.
Sorption-enhanced water gas shift reaction by sodium-promoted calcium oxides
Fuel
(2010) - et al.
The effect of SO2 on CO2 capture by CaO-based pellets prepared with a kaolin derived Al(OH)3 binder
Appl Energy
(2012) - et al.
Colloidal processing and CO2 capture performance of sacrificially templated zeolite monoliths
Appl Energy
(2012) - et al.
CO2 capture and attrition performance of CaO pellets with aluminate cement under pressurized carbonation
Appl Energy
(2012)
Preparation and characterization of novel CO2 “molecular basket” adsorbents based on polymer-modified mesoporous molecular sieve MCM-41
Microporous Mesoporous Mater
Aminopropyl-functionalized mesoporous silicas as CO2 adsorbents
Fuel Process Technol
A study on the activity of CaO-based sorbents for capturing CO2 in clean energy processes
Appl Energy
Advances in CO2 capture technology – the US Department of Energy’s carbon sequestration program
Int J Greenhouse Gas Control
Experimental studies on simultaneous removal of CO2 and SO2 in a polypropylene hollow fiber membrane contactor
Appl Energy
Fabrication and characterization of superhydrophobic polypropylene hollow fiber membranes for carbon dioxide absorption
Appl Energy
An overview of CO2 capture technologies
Energy Environ Sci
Worldwide innovations in the development of carbon capture technologies and the utilization of CO2
Energy Environ Sci
Separation and capture of CO2 from large stationary sources and sequestration in geological formations – coalbeds and deep saline aquifers
J Air Waste Manage Assoc
Innovative nano-layered solid sorbents for CO2 capture
Chem Commun
Novel regenerable sodium-based sorbents for CO2 capture at warm gas temperatures
Energy Fuels
Novel regenerable magnesium hydroxide sorbents for CO2 capture at warm gas temperatures
Ind Eng Chem Res
Dry potassium-based sorbents for CO2 capture
Catal Surv Asia
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