%0 Journal Article
%T Enzymatic Carbon Dioxide Capture
%A Alain C. Pierre
%J ISRN Chemical Engineering
%D 2012
%R 10.5402/2012/753687
%X In the past decade, the capture of anthropic carbonic dioxide and its storage or transformation have emerged as major tasks to achieve, in order to control the increasing atmospheric temperature of our planet. One possibility rests on the use of carbonic anhydrase enzymes, which have been long known to accelerate the hydration of neutral aqueous CO2 molecules to ionic bicarbonate species. In this paper, the principle underlying the use of these enzymes is summarized. Their main characteristics, including their structure and catalysis kinetics, are presented. A special section is next devoted to the main types of CO2 capture reactors under development, to possibly use these enzymes industrially. Finally, the possible application of carbonic anhydrases to directly store the captured CO2 as inert solid carbonates deserves a review presented in a final section. 1. Introduction One of the main problems our world is presently facing, concerns the capture of anthropic carbon dioxide rejected in the atmosphere by human activities. This gas is considered as one of the main atmospheric components responsible for a greenhouse effect and an increase of the earth atmosphere temperature [1, 2], with many unwanted consequences, including the development of infectious diseases [3]. According to a report by the International Panel on Climate Change (IPCC) on the earth climate evolution, dating from 2007, the release of this gas in the atmosphere has increased by 80% from 1970 to 2004 and it accounted for 76.7% of the ¡°Greenhouse Effects Gases¡± in 2004 [4]. An international agreement termed the ¡°Kyoto Protocol,¡± established by the United Nations Framework Convention on Climate Change, was initially signed in 1997 by 37 countries in order to reduce greenhouse gas (GHG) emissions [5]. This treaty was enforced in 2005 and the number of countries who ratified the convention increased to 191 in 2011. The target was to reduce the CO2 emission by an amount depending on the country by comparison with a defined basis (8% in Europe, 7% in USA), over the five-year period 2008¨C2012. Several methods are being developed or studied for this purpose [6, 7] and progress is being followed by the International Energy Agency (IEA) of the Organization for Economic Co-operation and Development (OECD) [8]. A general review was also published in a book chapter by Muradov [9]. Amongst them, one group of technology is proposing to use enzymes of the carbonic anhydrase type. The specificity of these enzymes is to catalyze the reversible transformation of neutral aqueous CO2 molecules, termed
%U http://www.hindawi.com/journals/isrn.chemical.engineering/2012/753687/