Syn-gas Production

Although many problems still remain to be overcome to make the process practical (not the least of which is the question of the corrosive nature of aqueous HBr and the minimization of formation of any higher brominated methanes), the selective conversion of methane to methyl alcohol without going through syn-gas has promise. Furthermore, the process could be operated in relatively low-capital-demand-ing plants (in contrast to syn-gas production) and in practically any location, making transportation of natural gas from less accessible locations in the form of convenient liquid methyl alcohol possible. 

SYNTHESIS OF OLIVINE (LiFeP04> and Ni/OLIVINE (LiFeP04) CATALYSTS FOR UPGRADING SYN-GAS PRODUCTION... 

Rapagna, S., Provendier, H., Petit, C. et al. (2002) Development of catalysts suitable for hydrogen or syn-gas production from biomass gasification. Biomass and Bioenergy, 22, 377-388. 

There is not space to discuss the details of syn. gas production here. The first reaction (steam reforming) is highly endothermic and involves an increase in entropy. It is carried out at high temperatures and moderate pressures (700-830°C/l5-40 atm) over a nickel catalyst supported on a-alumina or calcium aluminate and promoted by alkali metal oxides, which help to prevent the deposition of carbon. 

Formaldehyde reacts with syn gas (CO,H2) to produce added value products. Ethylene glycol (EG) may be produced in a two-stage process or the intermediate, glycolaldehyde, isolated from the first stage (65) ... 

Prior to 1975, reaction of mixed butenes with syn gas required high temperatures (160—180°C) and high pressures 20—40 MPa (3000—6000 psi), in the presence of a cobalt catalyst system, to produce / -valeraldehyde and 2-methylbutyraldehyde. Even after commercialization of the low pressure 0x0 process in 1975, a practical process was not available for amyl alcohols because of low hydroformylation rates of internal bonds of isomeric butenes (91,94). More recent developments in catalysts have made low pressure 0x0 process technology commercially viable for production of low cost / -valeraldehyde, 2-methylbutyraldehyde, and isovaleraldehyde, and the corresponding alcohols in pure form. The producers are Union Carbide Chemicals and Plastic Company Inc., BASF, Hoechst AG, and BP Chemicals. 

The purified syn gas next flows to the final production stage, which is anunonia synthesis and recovery. The first step is compression of tlie syn gas. Synthesis pressures range from 2000 to 10,000 psi depending on the quality of tlie syn gas and certain otlicr conditions, such as production requirements per converter," ... 

Here we shall have a closer look at the steam reforming process, which is used in large-scale industrial production of syn-gas and hydrogen. 

Velazquez-Vargas, L.G. et al., Hydrogen Production from Coal derived Syn Gas Using Novel Metal Oxide Particles, Proceedings of the 23th Annual International Pittsburgh Coal Conference, Pittsburgh, PA, September 2006. 

An alkene which will give a polar aldehyde product and syn gas are introduced into the reactor containing a non-polar ligand modified rhodium catalyst. Catalyst solution exiting the reactor enters a Flash stage where CO/H2 are purged. The catalyst solution then enters an extractor where it is contacted with a polar solvent. The product aldehyde is captured in the polar solvent in the extractor, then concentrated in the Solvent Removal Column. Polar Solvent is recycled to the Extractor. The Non-Polar catalyst solution is recycled to the reactor (see Figure 2.5). 

Fischer-Tropsch. Oct-l-ene is produced as one of the many products in the conversion of syn-gas and isolated by careful distillations and extractions of the mixture by Sasol. 

Ethanal is only used as an intermediate to acetic acid and its derivatives and in the near future production of ethanal will be replaced by other routes based on methanol and syn-gas to give acetic acid and acetic anhydride. Vinyl acetate can also be made via syn-gas routes, but the major producer in Europe employs a direct Wacker route with a heterogeneous palladium catalyst (former Hoechst ethene, acetic acid -from syn-gas-, and oxygen). 

Iridium(I) siloxide complexes-that is [ Ir( 4-OSiMe3)(cod) 2] and [Ir(cod)(PCy3)-(OSiMe3)]-have also been studied in the transformation of various vinylsilanes under pressure of syn-gas, giving mixtures of silylaldehydes accompanied by the hydrogenation product (Scheme 14.9) [57]. 

This report has described the development of a new process in which vinyl acetate is produced exclusively from methanol and syn gas with essentially no by-products. At best conditions, high conversions and selectivities are typical of the chemistry involved. Various process possibilities were described, thus permitting much flexibility for eventual development. 

Industrial development of homologation processes for dimethyl ether, methyl formate, methyl acetate and acetic acid is likely only if they are integrated into a comprehensive plant for the production of C2 derivatives from syn-gas (Scheme 5). 

Derivatives of the steroids androstene and pregnene have been transformed directly into A-acyl amino acids by an orthogonal catalysis procedure, utilizing [RhCl(nbd)]2 and Co2(CO)8 (Scheme 11). The rhodium phosphine catalyst (generated in situ in the presence of syn-gas and phosphine) affects hydroformylation of the internal olefin to generate aldehyde. In the presence of Co2(CO)8, A-acyl amino acids are obtained as the major products. An unstable amido alcohol intermediate, formed by reaction of the amide with aldehyde, is proposed to undergo cobalt-catalyzed GO insertion to yield the desired A-acyl amino acid. 

Hydrogen from syn gas reacts with nitrogen to produce ammonia N2 + 3H2 —> 2NH3. Carbon monoxide and hydrogen from syn gas can be combined to produce methanol CO + 2H2 —> CH3OH. Methanol is primarily used for the production of formaldehyde through... 

Butanal (butyraldehyde, CH3CH2CH2CHO) is made via hydroformy-lation (the OXO reaction). Although this is a general reaction of syn gas with alkenes to produce aldehydes, the largest poundage reaction of this type (in industry, generating the greatest volume of product) is the reaction of propylene with syn gas to yield butanal. 

We have our work divided into process engineering, process chemistry, catalysis, and support technology. As an example, one of the indirect liquefaction projects, tube wall reactor, deals with the design and operation of high thermal efficiency catalytic reactors for syn-gas conversion. Other activities are coal liquefaction properties of coal minerals, the role of catalysts, coal liquid product stability, and environmental impact—to name a few. 

In other applications where hydrogen is not the ultimate product, substantially all the hot syn gas from the gasifier may be directed through a heat recovery system where the sensible heat of the gas is used to generate steam for other process needs. 

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