Methanol distillation

If reagent-grade methanol from a previously unopened container is not available, it will be necessary to distill methanol for use in Procedure I from 1 g/liter KOH (pellets), discarding the first 10% of the distillate. 

In a lOOmL round-bottomed flask equipped with a magnetic stirrer bar were placed (7/f)-2-chloro-7-isopropyl-6,7-dihydro-5//-l-pyrindine (1.28 g), distilled methanol (16.5 mL), distilled ethyl acetate (16.5 mL) and rhodium on aluminum oxide (64.0 mg). The flask was connected to a hydrogen balloon and flushed with hydrogen. 

A degassed solution of potassium hydroxide (570 mg 9.62 mmol) in freshly distilled methanol (8mL) is prepared under nitrogen in a 50 mL round-bottomed flask equipped with a magnetic stirring bar. Solid Os6(CO)18 (150 mg 0.09 mmol) is added and the mixture is stirred at room temperature for 30 min. After addition of [PPN]C1 (Ventron) (330 mg, 0.57 mmol), the solution is cooled to — 25 °C for l6h. A brown powder is formed that is removed by filtration and washed with ice-cold methanol (10 mL). Yield 190 mg (85%). The compound does not need to be purified further. 

Acid-catalysed ester formation and hydrolysis are the exact reverse of one another the only way we can control the reaction is by altering concentrations of reagents to drive the reaction the way we want it to go. The same principles can be used to convert to convert an ester of one alcohol into an ester of another, a process known as transesterification. It is possible, for example, to force this equilibrium to the right by distilling methanol (which has a lower boiling point than the other components of the reaction) out of the mixture,... 

It can be prepared by introducing methyl alcohol into a nitrating mixture at a low temperature or by distilling methanol with medium-concentrated nitric acid. 

Prepare a solution of ethylenediamine (12 g, 0.2 mol) in distilled water (10 mL) in a ice-cooled conical flask (100 mL), and slowly add aqueous perchloric acid3 (70%, 17.2 mL) with gentle swirling. Remove the water on a rotary evaporator, periodically adding distilled methanol (5 x 10 mL) to aid azeotropic removal of the solvent. Once a white solid forms, carefully transfer the contents of the flask on to a crystallising dish, and place in a vacuum desiccator overnight. 

Add a Dean-Stark trap to the system (between the flask and condenser), distil methanol and methyl acetate until only about one-third ofthe solvent remains. Cool this mixture to 10°C. 

Azeotropic Distillation. Methanol may be used to separate toluene from cracked motor fuel fractions (51), and the use of sulfur dioxide in butane-butene separation has been reported by Matuszak and Frey (54). 

Crude methanol from the methanol synthesis will be distilled in order to remove the water content and hence improve the overall process economy. The distilled methanol is then converted to hydrocarbons in the fluid-bed reaction system. The hydrocarbon products are processed in a gas fractionation unit to produce C5 plus hydrocarbons, alkylation feed (C3/C4 fraction) and olefin recycle. The C3/C4 fraction is processed in the HF alkylation unit to produce alkylate. 

Distillate dewaxing Lube dewaxing Gas to aromatics Gas to Aromatics Light olefins to gasoline and distillate Methanol to gasoline Methanol to light olefins Xylene isomerization Toluene disproportionation Ethylbenzene synthesis 58-59) p-Xylene synthesis p-ethyltoluene synthesis... 

Equilibrium of this reaction is unfavorable and to achieve a high conversion, diphenyl carbonate is recovered by extractive distillation. Methanol can also be removed by molecular sieve adsorption to drive the reaction to higher conversion of DPC [28]. 

Another alternative for catalyst separation is the filtration after the catalyst has been precipitated. An interesting application is given by Fell and co-workers [35] for the hydroformylation of higher olefins by a methanol- and water-soluble rhodium catalyst. As shown in Figure 5, the reaction is carried out in a homogeneous methanol solution. After distillation of the methanol the catalyst is precipitated, filtered off, and again prepared with the distilled methanol. The products leave the process after the filtration step. 

Figure 9.7 TAME process with extractive-distillation methanol recovery.

D9. We are distilling methanol and water in a sieve plate column operating at 75% of flooding... 

Propargyl alcohol (15.1 mol, 848 g, freshly distilled), methanol (59.6 mol, 1908 g), and concentrated sulfuric acid (15 mmol, 1.47 g) were mixed and heated to 55 °C. A solution of Ph3PAuMe (148 pmol, 70.4 mg) in 125 mL of dioxane was then added within 10 h. The mixture was stirred for an additional 10 h, and then most of the remaining methanol was removed by distillation at reduced pressure. The residual solution was neutralized with 30% sodium methanolate in methanol and cooled in an ice bath. Precipitated product was collected by filtration and dried. A second batch of product can be obtained by further concentration of the mother liquor. Total yield of isolated product 1238 g (93%). 

Reaction conditions are very straightforward, consisting of stirring the aminophosphines 8 in freshly distilled methanol in the presence of 1 equivalent of sulfuric acid for several hours at 0 °C or room temperature. Methylpho-sphinite boranes 9 are either clear liquids or crystalline solids, which can be easily purified by column chromatography or recrystallisation and, in contrast to 8, are indefinitely stable in air. Another advantage is that the reaction yields one equivalent of unchanged ephedrine, which can be recycled. The reaction is... 

Acrylamide was purified by recrystallization from distilled methanol. 

Polymerization of pyrrole is performed by putting a 20-mL chloroform solution of pyrrole into 100-mL beakers. The concentrations of pyrrole can vary in the range 2.0 to 0.1 M. Then, 20 mL of a 0.2 M aqueous solution of ammonium persulfate is poured slowly on the chloroform solution within 10 s. The interface between chloroform and water starts to be colored and becomes black due to the formation of PPy at the interface. After 10 min, a film with a thickness of 3-4 pm is formed and removed with a glass or a Teflon plate. Then, a fresh interface appears and a new PPy film starts to be produced. A sufirdent amount of PPy is obtained by repeating the film-removing process described above. As-formed polymer films are rinsed with distilled methanol and dried in vacuum at 80 °C for 12 h. 

Along with walnut hulls and instant coffee, fhe amazing list of frac-furing fluid additives includes coffee grinds, salf, ceramic balls, lead petroleum distillates, methanol, benzene, toluene, xylene, and millions of gallons of diesel. The problem is that, in the absence of a minimum US national baseline for disclosure of fracking fluids combined with a special industry exemption from US. water safety standards, it s nearly impossible to assess any impact the use of these fluids may have on the environment or public health. It s trackin impossible (Nikiforuk, 2011). 

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