To produce methanol

E. Supp, How to Produce Methanol from Coal, Spriager-Vedag, Berlin, 1990. 

When the selectivity of a reaction is controlled by differences in the way molecules are activated on different sites, the probability of the presence of different sites becomes important. An example again can be taken from the activation of CO. For methanation, activation of the CO bond is essential. This will proceed with low barriers at step-edge-type sites. If one is interested in the production of methanol, catalytic surfaces are preferred, which do not allow for easy CO dissociation. This will typically be the case for terrace sites. The selectivity of the reaction to produce methanol will then be given by an expression as in Eq. (1.29a) ... 

Investigation of direct conversion of methane to transportation fiiels has been an ongoing effort at PETC for over 10 years. One of our current areas of research is the conversion of methane to methanol, under mild conditions, using li t, water, and a semiconductor photocatalyst. Research in our laboratory is directed toward ad ting the chemistry developed for photolysis of water to that of methane conversion. The reaction sequence of interest uses visible light, a doped tungsten oxide photocatalyst and an electron transfer molecule to produce a hydroxyl i cal. Hydroxyl t cal can then react with a methane molecule to produce a methyl radical. In the preferred reaction pathway, the methyl radical then reacts with an additional wata- molecule to produce methanol and hydrogen. 

Previous research by our groiqD [6] has confirmed literature reports [1,2] that it is possible to photolyze methane, saturated with water vapcff, to produce methanol and hydrogen. In a modification of the above ejq)eriment, we were also able to photolyze methane sparged throu a photochemical reactor filled with water. Recently, we began investigating the photocatalytic conversion of methane in water. 

Various attempts have been made to produce methanol by photoreduction of CO2 at semiconductor electrodes and particles (see e.g.) . In principle there is a good chance to produce methanol at a semiconductor because the conduction band can be... 

Direct partial oxidation of methane to produce methanol and other oxygenates... 

Oxidative coupling of methane to yield C2 and higher hydrocarbons 358 Direct partial oxidation of methane to produce methanol and other oxygenates 360... 

The process was further elaborated in the 1990s by Dong and Steinberg109 with the aim to produce methanol see, for example, Dong and Borgwardt.110... 

In addition to being a reducing agent in the production of metals, CO is used to produce methanol by the reaction... 

Colorless, oily liquid with a faint odor like onions. Vapors rapidly react with moisture in the air to produce methanol and sulfuric acid. 

Two configurations of stirred-tank reactors are to be considered for carrying out the reversible hydrolysis of methyl acetate (A) to produce methanol (B) and acetic acid (C) at a particular temperature. Determine which of the following configurations results in the greater steady-state rate of production of methanol ... 

When methanol is made from natural gas, the gas reacts with steam to produce synthesis gas, a mixture of hydrogen and carbon monoxide. This then reacts with a catalytic substance at high temperatures and pressures to produce methanol. The process is similar when methanol is produced by the gasification of biomass. The production of methanol from biomass or coal can cost almost twice as much as production from natural gas. 

The destructive distillation of wood to produce methanol results in some by-product acetic acid, and that was the most popular but now defunct commercial source. Fermentation, the oldest, indeed the ancient method, is still used to produce vinegar for the food industry. Vinegar is a 3—5% solution of acetic acid in water. 

CO and Hj react at high temperatures in the presence of a catalyst to produce methanol ... 

This enzyme [EC 1.14.13.25] catalyzes the reaction of methane with NAD(P)H and dioxygen to produce methanol, NAD(P), and water. This enzyme is reported to exhibit a broad specificity. Many alkanes can be hydrox-ylated and alkenes are converted into the corresponding epoxides. Carbon monoxide is oxidized to carbon dioxide, ammonia is oxidized to hydroxylamine, and some aromatic compounds and cyclic alkanes can also be hy-droxylated, albeit not as efficiently. 

Methanol. If one takes as an illustration the many propo-sals (16,1y) to use forest biomass to produce methanol as a motor fuel the R D priorities and the barriers can be identified. The production route is ... 

Catalyst solutions generated by the reaction of Ru(acac)3 or Ru3(CO)12 with H2/CO have been reported by Bradley to produce methanol and methyl formate as the major products (164, 165). Methyl formate is produced at a constant rate, suggesting that it is a primary product and not derived from... 

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... 

An industrial process to produce methanol from carbon monoxide and hydrogen was developed by BASF in 1923 using a zinc oxide-chromia catalyst.361 362 Since this catalyst exhibited relatively low specific activity, high temperature was required. The low equilibrium methanol concentration at this high temperature was compensated by using high pressures. This so-called high-pressure process was operated typically at 200 atm and 350°C. The development of the process and early results on methanol synthesis were reviewed by Natta 363... 

A mercury-catalyzed, high-yield system oxidizes methane by cone. H2SO4 to produce methanol 66... 

Methanol from biomass can also be costly because only relatively small amounts of it are produced through distillation. For this reason, most methanol today is produced from natural gas. The coal industry is even gearing up to produce methanol from its vast coal reserves. However, creating methanol from coal produces more pollution than is saved by burning the cleaner methanol. 

Methanol as Source ofSNG. Methanol can be produced from a large range of feedstocks by a variety of processes. Natural gas. liquefied petroleum gas (LPG), naphthas, residua] oils, asphalt, oil shale, and coal are in the forefront as feedstocks to produce methanol, with wood and waste products from farms and municipalities possible additional feedstock sources, hi order to synthesize methanol, the main feedstocks are converted to a mixture of hydrogen and carbon oxides (synthesis gas) by steam reforming, partial oxidation, or gasification. The hydrogen and carbon oxides are then converted to methanol over a catalyst. 

Another method of making economical use of remote natural gas reserves is to produce methanol from them. Methanol can easily be transported via ocean tanker without losses, unlike LNG. 

Eliasson et al. [1, 73-77] reported a silent discharge C02 hydrogenation in the presence or absence of a catalyst to produce methanol. A radical reaction mechanism [75] has been presented to explain the observed phenomena, and can be expressed as ... 

Similarly, when Bockris and Wass used various organic mediators in a DMF solution with 5% water and p-CdTe as the photocathode [120], the bare p-CdTe produced a faradaic efficiency for CO of 92%. Subsequently, by using their best catalysts, namely 15-crown-5 ether and 18-crown-6 ether, these authors were able also to produce methanol with faradaic efficiencies of 14% and 13%, respectively, with the remaining current going to CO production. Although the potential at which these electrolyses were carried out was not reported, the onset potential for C02 reduction was shifted some 400 mV anodically in the presence of the organic mediators. 

Whilst many studies of metal-coated Ti02 powders and colloids for the reduction of C02 have been reported [135], Ti02 alone seems ineffective for C02 reduction. Adachi et al. was able to reduce C02 to methane, ethane, and ethylene in aqueous solution using Cu-loaded Ti02 powders [136]. Likewise, others were able to produce methanol almost selectively with both Rh- and W03-doped Ti02 powders. The... 

The wild card that ethylene producers must watch for is the emergence of new technologies that could tap other low-cost feeds, particularly if crude oil-linked feedstock prices stay high. Foremost is conversion of methanol into olefins (MTO), using low-cost methanol sourced from the world s abundant supplies of stranded natural gas. While this technology is as yet unproven on a large scale, in theory the world s huge volumes of untapped stranded gas could be used to produce methanol which could be converted to olefins and polymers in situ, or shipped to end markets such as China and converted to olefins and polymers there. 

Power plants using fuel cells can now take the place of the present polluting coal or oil-based (indirect) electricity-producing plants. However, in a further development, it would be possible to extract COz from the atmosphere, and H2 from solar-driven electrolysis, to produce methanol with zero net injection of C02 into the atmosphere. These plants would at first ran on hydrogen from these fossil fuels, the attraction being the reduction of pollution and the increase in the conversion efficiency. To what extent the latter two commodities would be supplied from remote sites, or collected onsite at... 

Methanol. As is the case with ethanol, the concept of producing methanol from wood is not new. Methanol obtained from the destructive distillation of wood represented the only commercial source until the 1920s. The yield of methanol from wood by this method is low, only about 1-2 percent or 20 L/metric ton (6 gal/ton) for hardwoods and about one-half that for softwoods. With the introduction of natural gas technology, the industry gradually switched to a synthetic methanol formed from a synthesis gas (syngas) produced from reformed natural gas. Two volumes of H2 and one volume of CO are reacted in a catalytic converter at pressures of 1500-4000 psi to produce methanol. Presently, 99 percent of the methanol produced in the United States is derived from natural gas or petroleum. 

It was shown (Ovanesyan et al., 2000) that iron complexes formed during the thermal treatment of FeZSM-5 zeolite perform single-turnover cycles of methane oxidation to methanol at ambient conditions when nitrous oxide is used as a source of oxygen. The long-living active intermediate is capable of transferring an accepted O atom into a C-H bond of methane to produce methanol at 100% selectivity. On the basis of joint Mossbauer and catalytic data, the structure and composition of iron active centers are suggested. 

Application To produce methanol from natural or associated gas feedstocks using advanced tubular reforming followed by boiling water reactor synthesis. This technology is an option for capacities up to approximately 3,000 mtpd methanol for cases where carbon dioxide (C02) is available. Topsoe also offers technology for larger-scale methanol facilities up to 10,000 mtpd per production train and technology to modify ammonia capacity into methanol production. 

---