Reaction Characteristics of Wastepaper Gasification With CO2 Catalyzed by Molten Carbonate Salts

2002 ◽  
Author(s):  
Hiroyuki Iwaki ◽  
Gong Jin ◽  
Tomohiko Furuhata ◽  
Norio Arai
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Critical Role ◽  
Boudouard Reaction ◽  
Low Carbon ◽  
Molten Carbonate ◽  
Steam Generation ◽  
Different Temperatures ◽  
Effective Use ◽  
Carbonate Salts

In this paper, wastepaper gasification with steam and carbon dioxide was tested in the presence of molten carbonate salt catalysts. Reactions with steam or carbon dioxide were first compared. Hydrogen was mainly produced by gasification with steam, but no carbon monoxide was generated. For the case where carbon dioxide was used as a reactant instead of steam, generation of carbon monoxide greatly increased via the Boudouard reaction. Different ratios of mixtures of lithium, sodium and potassium carbonates were examined. Lithium was found to play a critical role in the various catalyst combinations. The reaction rate with respect to carbon conversion was approximately first order for low carbon conversions. The rate constants were investigated at different temperatures (923–1023K) and the activation energies were determined. In addition, the flexibility of this technique was examined with three different types of wastepaper. These results suggest the applicability of this process for the effective use of wastepaper and recovery of carbon dioxide.

Low-Carbon Monoxide Hydrogen by Sorption-Enhanced Reaction

2003 ◽  
Vol 1 (1) ◽  
Author(s):  
Douglas P Harrison ◽  
Zhiyong Peng
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Hydrogen Production ◽  
Proton Exchange Membrane ◽  
Primary Energy ◽  
Proton Exchange ◽  
Raw Material ◽  
Impurity Level ◽  
Low Carbon ◽  
Enhanced Production

Hydrogen is an increasingly important chemical raw material and a probable future primary energy carrier. In many current and anticipated applications the carbon monoxide impurity level must be reduced to low-ppmv levels to avoid poisoning catalysts in downstream processes. Methanation is currently used to remove carbon monoxide in petroleum refining operations while preferential oxidation (PROX) is being developed for carbon monoxide control in fuel cells. Both approaches add an additional step to the multi-step hydrogen production process, and both inevitably result in hydrogen loss. The sorption enhanced process for hydrogen production, in which steam-methane reforming, water-gas shift, and carbon dioxide removal reactions occur simultaneously in the presence of a nickel-based reforming catalyst and a calcium-based carbon dioxide sorbent, is capable of producing high purity hydrogen containing minimal carbon monoxide in a single processing step. The process also has the potential for producing pure CO2 that is suitable for subsequent use or sequestration during the sorbent regeneration step. The current research on sorption-enhanced production of low-carbon monoxide hydrogen is an extension of previous research in this laboratory that proved the feasibility of producing 95+% hydrogen (dry basis), but without concern for the carbon monoxide concentration. This paper describes sorption-enhanced reaction conditions – temperature, feed gas composition, and volumetric feed rate – required to produce 95+% hydrogen containing low carbon monoxide concentrations suitable for direct use in, for example, a proton exchange membrane fuel cell.

scholarly journals One-pot synthesis of nanostructured carbon materials from carbon dioxide via electrolysis in molten carbonate salts

Carbon ◽  
2016 ◽  
Vol 106 ◽  
pp. 208-217 ◽  
Author(s):  
Hongjun Wu ◽  
Zhida Li ◽  
Deqiang Ji ◽  
Yue Liu ◽  
Lili Li ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Carbon Materials ◽  
Nanostructured Carbon ◽  
Molten Carbonate ◽  
One Pot ◽  
One Pot Synthesis ◽  
Carbonate Salts

Reactions of carbon with atomic gases

1959 ◽  
Vol 12 (4) ◽  
pp. 533 ◽  
Author(s):  
JD Blackwood ◽  
FK McTaggart
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Water Vapour ◽  
Active Sites ◽  
Atmospheric Temperature ◽  
Carbon Surface ◽  
Hydrogen Atoms ◽  
Different Temperatures ◽  
Atomic Species ◽  
Oxygen Groups

Wood chars were reacted at atmospheric temperature with hydrogen atoms, oxygen atoms and carbon monoxide, hydrogen atoms and hydroxyl radicals, produced by the action of a radio frequency field on hydrogen, carbon dioxide, and water vapour respectively. The chars were prepared at different temperatures and contained different amounts of oxygen. The experimental results showed that the gases must be present in the atomic form before reaction with the carbon can take place and that such species react on the carbon-surface independently of active sites. In normal gasification processes the atomic species appear to be produced at active centres, which for the chars used could be correlated with specific oxygen groups remaining in the carbon. It is suggested that these groupings may have a pyran structure. An explanation has been put forward for the retardation of the carbon-water vapour reaction by hydrogen, and of the carbon-carbon dioxide reaction by carbon monoxide. These are considered as due to reverse mechanisms which decrease the concentration of the atomic species and not to the blocking of active sites by adsorption of the retardant.

Study on the gasification of wastepaper/carbon dioxide catalyzed by molten carbonate salts

Energy ◽  
2005 ◽  
Vol 30 (7) ◽  
pp. 1192-1203 ◽  
Author(s):  
Gong Jin ◽  
Hiroyuki Iwaki ◽  
Norio Arai ◽  
Kuniyuki Kitagawa
Keyword(s):  
Carbon Dioxide ◽  
Molten Carbonate ◽  
Carbonate Salts

scholarly journals Carbon electrodeposition in molten salts: electrode reactions and applications

RSC Advances ◽  
2014 ◽  
Vol 4 (67) ◽  
pp. 35808-35817 ◽  
Author(s):  
Happiness V. Ijije ◽  
Richard C. Lawrence ◽  
George Z. Chen
Keyword(s):  
Carbon Dioxide ◽  
Molten Salts ◽  
Molten Carbonate ◽  
Energy Materials ◽  
Electrode Reactions ◽  
Carbonate Salts

Carbon dioxide can be electrochemically reduced to carbon in molten carbonate salts, promising affordable energy, materials and environmental explorations.

scholarly journals Co-pyrolysis of rubberwood sawdust (RWS) and polypropylene (PP) in a fixed bed pyrolyzer

2019 ◽  
Vol 13 (1) ◽  
pp. 4636-4647 ◽  
Author(s):  
N. I. Izzatie ◽  
M. H. Basha ◽  
Y. Uemura ◽  
M. S. M. Hashim ◽  
M. Afendi ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Water Content ◽  
Fixed Bed ◽  
Oil Yield ◽  
Pyrolysis Oil ◽  
Pyrolysis Process ◽  
Increasing Trend ◽  
Different Temperatures

Co-pyrolysis of rubberwood sawdust (RWS) waste and polypropylene (PP) was carried out at different temperatures (450,500,550, and 600°C) with biomass to plastics ratio 1:1 by using fixed bed drop-type pyrolyzer. The yield of pyrolysis oil has an increasing trend as the temperature increased from 450°C to 550°C. However, the pyrolysis oil yield dropped at a temperature of 600°C. Co-pyrolysis of RWS and PP generated maximum pyrolysis oil with 36.47 wt.% at 550°C. The result is compared with the pyrolysis of RWS only without plastics, with the same feedstock, and the maximum pyrolysis oil yield obtained was 33.3 wt.%. The water content in pyrolysis oil of co-pyrolysis RWS with PP is lower than RWS only with 54.2 wt.% and 62 wt.% respectively. Hydrocarbons, acyclic olefin, alkyl, and aromatic groups are the major compound in the pyrolysis oil from the co-pyrolysis process. Carbon monoxide (52.2 vol.%) and carbon dioxide (38.2 vol.%) are the major gas components.

The Reaction of Carbon with Carbon Dioxide at High Pressure

1960 ◽  
Vol 13 (2) ◽  
pp. 194 ◽  
Author(s):  
JD Blackwood ◽  
AJ Ingeme
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Active Sites ◽  
High Pressures ◽  
Carbon Dioxide Molecule ◽  
Partial Pressures ◽  
Different Temperatures ◽  
Adsorbed Carbon ◽  
Forward Process ◽  
High Carbon Dioxide

A study has been made of the reactions of purified carbon with carbon dioxide at pressures up to 40 atm and in the temperature range 790-870 �C. The effect of carbon monoxide has been examined by adding varying proportions of this gas to the carbon dioxide supplied to the reactor bed. At high carbon dioxide and carbon monoxide partial pressures, the rate of formation of carbon monoxide is greater than would be expected from the mechanism proposed by Gadsby et al. (1948). A mechanism has been proposed whereby the increased rate may be explained by additional steps involving the interaction of a carbon dioxide molecule with an adsorbed carbon monoxide to produce adsorbed oxygen, thus : ������������������ CO2 + (CO) → 2CO +(O) A general rate equation has been derived which includes this step and satisfies the experimental results. The reverse mechanism by which carbon monoxide can disappear is not the simple reverse of the forward process and at high pressures equilibrium cannot be expressed by the usual expression derived for the simple single-stage reversible process. The possible nature of active sites has been examined by studying the reactivity of a series of chars prepared at different temperatures. The reactivity appears to be related to the oxygen content of the chars and the type of active centres involved may be different from those which control the carbon-steam mechanism.

Utilisation of Carbon Dioxide for Electro-Carburisation of Mild Steel in Molten Carbonate Salts

2011 ◽  
Vol 158 (11) ◽  
pp. H1117 ◽  
Author(s):  
Nancy J. Siambun ◽  
Harimi Mohamed ◽  
Di Hu ◽  
Daniel Jewell ◽  
Yeo K. Beng ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Mild Steel ◽  
Molten Carbonate ◽  
Carbonate Salts
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