Sunday, September 8, 2019

Methane Dry Reforming Research Paper Example | Topics and Well Written Essays - 1250 words

Methane Dry Reforming - Research Paper Example The active use of methane and carbon dioxide is also helpful because these gases are not environmentally friendly and their conversion to feedstock will enable better environmental regulation. During the conversion process, one of the major problems is catalyst deactivation resulting from coke deposition. The deposition of coke produces poor catalyst selectivity, activity and longevity. The aim of this project is to investigate the effects of forced periodic cycling between a carbon-gasifying agent (such as carbon dioxide) and methane dry reforming in order to increase the yield of syngases and to improve catalyst longevity. This study will also bolster innovation by developing the traditional Ni-CO catalyst using cerium oxide as a promoter. This approach has been shown to favour synthesis gas formation along with resistance to coking in various studies on the matter. The achievement of these goals may lead to significant improvements in hydrocarbon reforming in context of catalyst d eactivation and would also lead to an improved catalytic reforming system. These improvements would in turn provide substantial economic and environmental benefits through a positive reduction in greenhouse gases. 1. Literature Review 1.1. Introduction Both large scale and small scale industrial technology has depended on hydrocarbon reforming to produce hydrogen [Seo et al., 2009; Rakib et al., 2010]. One of the largest uses for hydrogen is the production of ammonia (NH3) through a reaction with nitrogen using the Haber process [Li et al., 2007]. Steam reforming is also a preferred method to produce hydrogen at high purity and product yields for small energy technologies like fuel cells [Lora et al.; Heinzel et al., 2002]. Overall, the major processes involved in the conversion of hydrocarbons to synthesis gas include dry reforming, steam reforming and partial oxidation or a combination of partial oxidation and steam reforming better known as oxidative steam reforming [Aasbe rg-Petersen et al., 2001; Sarmiento et al., 2007; Rostrup-Nielsen, 2009]. Each of these processes tend to have their own pros and cons based on criteria such as product composition, availability of reactants (CO2, H2O, O2), purity as well as production scale and cost [Pena et al., 1996]. As far as refining and petrochemical processes are concerned steam reforming is the preferred method [AvcI et al., 2004]. However, the industrial production of synthesis gas using hydrocarbon steam reforming tends to leave behind unwanted coke deposits on the catalyst making it not so favourable. Coke deposition has distinct disadvantages including lowered catalyst activity, longevity, selectivity and reduced reactor performance that requires constant maintenance. Within industrial processes, carbon is removed using an excess carbon to steam ratio (generally greater than 3) in order to decrease the chances of coke deposition on the catalyst. Though this method is effective, it requires greater energy investment as more steam is required than normal steam reforming necessitates. On the other hand, dry reforming is seen as an auspicious technology for synthesis gas production as it offers certain distinct advantages such as: i. Depletion of unwanted greenhouses gases (carbon dioxide and methane); ii. Gas separation is not required thereby reducing cost and allowing

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