Specification, methanol

The quantitative analysis procedure involves benz extr of TNT, water extr of AN, and taking of the A1 content as insol residue. Moisture content is detd by the Karl Fischer method described in ASTM Method E203-62, except that 8 to lOg samples are added to methanol. Specific gravity is detd by water displacement, and workmanship by visual examination... 

Figure 19. Battelle s methanol specific reforming catalyst. Reactor conditions atmospheric pressure, reactant feed 50 50 by weight methanol and water mixture, 24 000— 50 000 ii GHSV. The conversion was reported as moles methanol reacted/moles methanol fed. (Reprinted with permission from ref 91. Copyright 2002 Elsevier.)...

After the condensed crude methanol is recovered in the high-pressure separator, it is sent to a methanol purification column. Typically, methanol purification requires two columns, one to remove the light ends (mainly by-products generated in the methanol synthesis reactor such as dimethyl ether and dissolved gases) and another to separate methanol and water and any other by-products with a lower volatility than methanol. Specification-grade methanol (greater than 99.85 wl% methanol) is recovered as the overhead product of the heavy ends column and sent to storage. 

Density of methanol = (Specific gravity)(Density of water)... 

Amines. Benzene solutions o-f Fe3nitro group oi nitroaryls to a primary amine in the presence of functional groups without methanol no amine is obtained [63]. No azo, azoxy, or CO insertion products are formed. 

The structure of chlc2 in liquid methanol, specifically the coordination of the chromophore metallic center to the methanol molecules can be discussed by representing the radial distribution function [RDF(r)] related to Mg-O interactions. A relevant issue concerns the coordination number of the metalic center. BOMD results for the structure indicate that the coordination number for Mg of chlc2 in liquid methanol is five [114] a feature that seems to be related with the displacement of the metallic center from the macrocycle plane. This is in contrast with the results from force field calculations that indicate a coordination number of six (four nitrogen atoms plus two oxygen atoms). Several works discussed the coordination of the central Mg atom of porph3rins and chlorophylls in different solvents and environments [112, 118, 134—138]. 

Compared with chemical methanol, the cost of shipping fuel methanol by sea should be significantly lower for two reasons. The first is that the exceptionally hi purity required of chemical methanol necessitates costfy delays while tankers are cleaned and inspected, and further expenses are associated with provision of dedicated tankers, analyses, and insurance. All these can be largely avoided since the fuel methanol specification allows considerably more latitude in impurity content. Second, because fixel methanol will be delivered in bulk to relatively few customers, supertankers can be used there is no reason that methanol should cost more per gallon to ship than any other liquid shipped in comparable volumes. Thus the ultimate cost of shipping methanol should be the same as crude oil, per gallon. 

The other means of transporting large volumes of liquid is via pipelines, a method that offers very significant benefits over road or rail transport. Despite frequent assertions that methanol pipelining would not be practicable, methanol has been very successfully transferred by pipeline in two demonstrations conducted in Canada in 1986. One demonstration involved a crude oil line running from Edmonton, Alberta to Burnaby, British Columbia, a distance of 716 miles the other used a liquefied petroleum pipeline over a distance of 1819 miles. Figure 5 shows analyses of the two shipments, each of which comprised 4000 t. In both cases, the transfer was effected well within the impurity limits dictated by any proposed fuel methanol specification. Such pipelined distribution of methanol must become standard if a significant fraction of the ciurent transportation fuel market is ined by fuel methanol (see Table 5). 

Table 11 CaHfomia Air Resources Board M85 Fuel Methanol Specification...

The sum of the downstream costs adds roughly 7.9 cents per Hter (300/gal) and the adjustment of the final cost for an amount of methanol fuel equivalent ia distance driven to an equal volume gasoline involves a multiplier ranging from 1.6 to 2.0, depending on fuel specification and the assumed efficiency for methanol light-duty vehicles as compared to gasoline vehicles. The California Advisory Board has undertaken such cost assessment (11). 

In reviewing the fiiU range of health and safety issues associated with all alternative fuels, the California Advisory Board determined that there were no roadblocks that would prevent the near term deployment of either methanol or ethanol, assuming that adequate safety practices were foUowed appropriate to the specific nature of each fuel (14). 

In 1973 the Semiconductor Equipment and Materials Institute (SEMI) held its first standards meeting. SEMI standards are voluntary consensus specifications developed by the producers, users, and general interest groups in the semiconductor (qv) industry. Examples of electronic chemicals are glacial acetic acid [64-19-7] acetone [67-64-17, ammonium fluoride [12125-01 -8] and ammonium hydroxide [1336-21 -6] (see Ammonium compounds), dichloromethane [75-09-2] (see Cm.OROCARBONSANDcm.OROHYDROCARBONs), hydrofluoric acid [7664-39-3] (see Eluorine compounds, inorganic), 30% hydrogen peroxide (qv) [7722-84-1] methanol (qv) [67-56-1] nitric acid (qv) [7697-37-2] 2-propanoI [67-63-0] (see Propyl alcohols), sulfuric acid [7664-93-9] tetrachloroethane [127-18-4] toluene (qv) [108-88-3] and xylenes (qv) (see also Electronic materials). 

Procedures for determining the quaUty of formaldehyde solutions ate outlined by ASTM (120). Analytical methods relevant to Table 5 foUow formaldehyde by the sodium sulfite method (D2194) methanol by specific gravity (D2380) acidity as formic acid by titration with sodium hydroxide (D2379) iron by colorimetry (D2087) and color (APHA) by comparison to platinum—cobalt color standards (D1209). 

Formaldehyde—Alcohol Solutions. These solutions are blends of concentrated aqueous formaldehyde, the alcohol, and the hemiacetal. Methanol decreases the average molecular weight of formaldehyde oligomers by formation of lower molecular weight hemiacetals. These solutions are used to produce urea and melamine resins the alcohol can act as the resin solvent and as a reactant. The low water content can improve reactivity and reduce waste disposal and losses. Typical specifications for commercially available products are shown in Table 7 (117). 

The quahty of formamide suppHed by BASE is certified as having a minimum assay of 99.5%. The principal impurities in the material are ammonium formate, methanol, water, and traces of iron. The quaUty of formamide supphed by BASE is certified to meet the specifications given in Table 3. 

In the early 1920s Badische Arulin- und Soda-Fabrik aimounced the specific catalytic conversion of carbon monoxide and hydrogen at 20—30 MPa (200—300 atm) and 300—400°C to methanol (12,13), a process subsequendy widely industrialized. At the same time Fischer and Tropsch aimounced the Synth in e process (14,15), in which an iron catalyst effects the reaction of carbon monoxide and hydrogen to produce a mixture of alcohols, aldehydes (qv), ketones (qv), and fatty acids at atmospheric pressure. 

Mixtures of products are frequentiy observed. Oxidation by peroxycarboxylic acids usually give similar products (22). Several chemical oxidants give good yields of specific oxidation products. Dimethyl sulfoxide in aqueous acid gives oxindoles (23). In methanol, MoO HMPA (hexamethylphosphoramide) gives 3-hydroxy-2-methoxyindolines (24). 

Solid-Bed Caustic Treatment. SoHd-bed caustic units utilizing methanol [67-56-1] injection into the LPG feed stream can be used for carbonyl sulfide removal. The methanol—caustic solution must be drained periodically from the beds and discarded. When the soHd bed is exhausted, the spent caustic must be discarded and replaced. The LPG from the treater has a low enough water content to meet the propane specification. 

Fumaric acid is sold as resia-grade and food-grade. The general sales specification under which resia-grade fumaric acid is sold ia the United States specifies white, crystalline granules with a minimum assay of 99.6% and maximum ash content of 0.05%. The moisture specification is 0.3% maximum with < 10 ppm heavy metals. The color of a 5% solution ia methanol is to be less than 10 APHA. Food-grade fumaric acid calls for somewhat lower impurity levels. Particle size and particle size distribution are important ia many appHcations. 

The advent of a large international trade in methanol as a chemical feedstock has prompted additional purchase specifications, depending on the end user. Chlorides, which would be potential contaminants from seawater during ocean transport, are common downstream catalyst poisons likely to be excluded. Limitations on iron and sulfur can similarly be expected. Some users are sensitive to specific by-products for a variety of reasons. Eor example, alkaline compounds neutralize MTBE catalysts, and ethanol causes objectionable propionic acid formation in the carbonylation of methanol to acetic acid. Very high purity methanol is available from reagent vendors for small-scale electronic and pharmaceutical appHcations. 

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