Methanol total

FIGURE 1.6 Effect of organic modifier (methanol) percentage in the elnent on the retention factors (a) and observed enantioselectivities (b) of Af-(2,4-dinitrophenyl)-a-(2-chlorobenzyl)-proline employing an 0-9-[(2,6-diisopropylphenyl)carbamoyl]quinine-based CSP. Experimental conditions Elnent, ammonium acetate buffer-methanol (total ionic strength = 25 mM pHj, = 6.5), methanol content varied between 60 and 90%, while ionic strength and apparent pH were kept constant temperature, 40 C flow rate, 0.8 mLmin . (Reproduced from A. Peter et al., J. Sep. ScL, 26 1125 (2003). With permission.)... 

SUBS-TI Dissolve 28 mg linoleic acid in 1.97 ml methanol (total volume 2 ml). Seal in a 2-ml vial with a screw cap equipped with a Teflon-lined septum, and store up to a few months under argon at -20°C. 

Collect the ACN in a PP tube. Add another 15 ml of ACN to sample residue and shake, centrifuge and elute through the above florisil/carbon column. Combine the 2 ACN eluates. Then elute with 5 ml methanol through the column. Combine ACN and methanol (total 50 ml) and blow it down to dryness under a gentle stream of nitrogen. Reconstitute the solvent with 1ml methanol and filter it through the nylon filter, prior to instrumental analysis. 

Energy crop 20% Methanol in water 60% Methanol in water 100% Methanol Total phenolics valueb... 

Trioleine Methanol Total Methyl ester Glycerol Total... 

Topsoe supplies a complete range of catalysts for methanol production. The total energy consumption for this process scheme is about 7.1 Gcal/ton methanol. Total energy consumption for production of fuel grade methanol is approximately 6.8 Gcal/ton methanol. 

Economics Energy consumption for a stand-alone plant, including utilities and oxygen plant, is about 30 GJ/metric ton of methanol. Total installed cost for a 5,000-mtpd plant including utilities and oxygen plant is about US 350 million, depending on location. 

Recently we completed an evaluation of the effectiveness of the Aflatest (Vicam) immunoaffinity column for analysis of corn, peanuts and peanut butter for aflatoxin (11). In this procedure the sample is extracted with Me0H/H20, filtered, and the extract diluted to <30% MeOH with water. An aliquot is then applied to the immunoaffinity column. The column is then washed with water and the aflatoxins eluted with methanol. Total aflatoxins are then determined by solution fluorometry with bromine (SFB), or individual toxins by reverse phase high performance liquid chromatography with post column I2 derivatization (PCD). In the collaborative study corn samples naturally contaminated with aflatoxins and samples of corn, peanuts and peanut butter spiked at 30, 20 and 10 ng/g, were analyzed by 24 collaborators. The results of this study are tabulated in Table V. 

Homologation experiments were conducted in a 300 ml pressure reactor ( M/s Parr Inst., Co. U.S.A ). In a typical run, known amount of catalyst is mixed with known volumes of aqueous HI and methanol (total volume 50 ml) and placed in the reaction vessel. The reactor was pressurized to 30 atm CO and was maintained at 150 C. After 11 h contact time, the reactor was cooled to room temperature and analyzed for the products. Dimethyl ether formation was confirmed by passing the gaseous product through iodine in CS2 solution which gave tany colour. It was quantitatively analyzed by gas chromatography using molecular sieve 13X packed s.s column and TCD detector. Acetic acid and dimethylacetate were analyzed by GC ( Shimadzu, Japan ) and confirmed by their standards. 

Under the best reported conditions (concerning activity) for the aforementioned catalytic systems (use of Rh(acac)(CO)2, molar ratios Rh/Phen = 1, PhNOa/Rh = 250, PhNH2/Rh = 125, 160 °C, 68 atm in methanol, total volume 75 ml) a total conversion was reached in 2 h (plus 1.5 h required to reach the final temperature), with a 80 % selectivity in methyl phenylcarbamate, 15 % in aniline, 6 % in N-methyleneaniline, and 1 % in N-methylaniline. Use of [Rh(CO)2Cl]2 as catalyst under the same conditions gave a slower, but more selective reaction (3 h at 160 °C to reach complete conversion, with a 89 % selectivity in carbamate) [164], An even higher selectivity (96 %) was reported for the pyridine-promoted reaction (Py = 25 ml), although a lower catalytic ratio (166.7) was used in a reaction run for 5.5 h at 130 °C [165] with [Rh(CO)2Cl]2 as catalyst. Unfortunately, the examples were chosen is such a way to prevent a complete comparison of the different catalyst-cocatalyst combinations imder exactly the same experimental conditions, so that it is impossible to say which is the best. 

General Procedure for the Pd-Catalyzed Deprotection of the Benzylidene Protecting Group. To a round-bottom flask charged with the first generation protected carborane polymer, [G-l]-(Bn), was added a 1 1 mixture of CH2Cl2 methanol (total of 20 mL). Subsequently, Pd(OH)2/C (20%) was added and the flask was evacuated and back-filled with H2 three times (H2 pressure 1... 

The observation that bulk metal vanadates posses a high selectivity toward formaldehyde strongly suggests that the surface of bulk metal vanadates is composed of vanadium oxide sites with redox properties that cover the counter-cation sites (Mg, Ni, Mn, Cr, Co, Zn, Al, Nb, Fe, Cu, and Ag) thus, inhibit methanol total oxidation. The TOF values of the bulk metal vanadates are similar indicating that there is no significant influence of the specific nature of the metal oxide counter-cation on the catalytic behavior. Moreover, there are significant differences between the TOF values of bulk metal vanadates and pure metal oxides. 

Moderate errors in the total pressure calculations occur for the systems chloroform-ethanol-n-heptane and chloroform-acetone-methanol. Here strong hydrogen bonding between chloroform and alcohol creates unusual deviations from ideality for both alcohol-chloroform systems, the activity coefficients show... 

In a conventional gasoline containing hydrocarbons or even ethers, the presence of water is not a problem in fact, water is totally soluble up to about 50 ppm at ambient temperature. Beyond this value water separates without affecting the hydrocarbon phase and the water leg can be withdrawn if necessary. On the other hand, in the presence of alcohols (ethanol and especially methanol), trace amounts of water can cause a separation of two phases one is a mixture of water and alcohol, the other of hydrocarbons (Cox, 1979). 

The tendency to separate is expressed most often by the cloud point, the temperature at which the fuei-alcohol mixture loses its clarity, the first symptom of insolubility. Figure 5.17 gives an example of how the cloud-point temperature changes with the water content for different mixtures of gasoline and methanol. It appears that for a total water content of 500 ppm, that which can be easily observed considering the hydroscopic character of methanol, instability arrives when the temperature approaches 0°C. This situation is unacceptable and is the reason that incorporating methanol in a fuel implies that it be accompanied by a cosolvent. One of the most effective in this domain is tertiary butyl alcohol, TBA. Thus a mixture of 3% methanol and 2% TBA has been used for several years in Germany without noticeable incident. 

All of this careful addition is to keep the reaction from starting before the bomb is sealed. It is also important to note that the chemist must scale up or scale down the amount of reactants so that the total amount of all the ingredients consumes no less than 90 of the volume space of her particular pipe bomb. Too much head space with its atmospheric air will lower the yield. The bomb is heated in an oil bath or oven at 105-115°C for 18-24 hours and the contents are then distilled with the 1,3 benzodioxole coming over at about 170-175°C with no vacuum, Alternatively, the chemist can only distill off the methanol, wash with dilute NaOH solution and extract with ether, etc. 

Analytical Procedures. Standard methods for analysis of food-grade adipic acid are described ia the Food Chemicals Codex (see Refs, ia Table 8). Classical methods are used for assay (titration), trace metals (As, heavy metals as Pb), and total ash. Water is determined by Kad-Fisher titration of a methanol solution of the acid. Determination of color ia methanol solution (APHA, Hazen equivalent, max. 10), as well as iron and other metals, are also described elsewhere (175). Other analyses frequendy are required for resia-grade acid. For example, hydrolyzable nitrogen (NH, amides, nitriles, etc) is determined by distillation of ammonia from an alkaline solution. Reducible nitrogen (nitrates and nitroorganics) may then be determined by adding DeVarda s alloy and continuing the distillation. Hydrocarbon oil contaminants may be determined by ir analysis of halocarbon extracts of alkaline solutions of the acid. 

Coa.1 Reserves. As indicated in Table 2, coal is more abundant than oil and gas worldwide. Moreover, the U.S. has more coal than other nations U.S. reserves amount to about 270 biUion metric tons, equivalent to about 11 x 10 MJ (1 x 10 ° BTU = 6600 quads), a large number compared to the total transportation energy use of about 3.5 x lO " MJ (21 quads) per year (11). Methanol produced from U.S. coal would obviously provide better energy security benefits than methanol produced from imported natural gas. At present however, the costs of producing methanol from coal are far higher than the costs of producing methanol from natural gas. 

Fig. 5. Emissions from a GM Corsica VFV for gasoline and gasoline—methanol mixtures where represents total organic material, including hydrocarbons, methanol, and formaldehyde U represents NO formaldehyde and Hcarbon monoxide.

The nameplate capacity of worldwide methanol plants is given by country in Table 2 (27). A significant portion of this capacity is based on natural gas feedstock. Percent utilization is expected to remain in the low 90s through the mid-1990s. A principal portion of this added capacity is expected to continue to come from offshore sources where natural gas, often associated with cmde oil production, is valued inexpensively. This has resulted in the emergence of a substantial international trade in methanol. In these cases, the cost of transportation is a relatively larger portion of the total cost of production than it is for domestic plants. 

---