The Propane-Methanol System

Parameter Value Standard Deviation Objective Function 

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Table 14.4 Parameter Estimates for the Propane-Methanol System...

Figure 14.4 Vapor-liquid equilibrium data and calculated values for the propane-methanol system [reprinted from the Canadian Journal of Chemical Engineering with permission].

Galivel - Solastiuk F., S. Laugier and D. Richon, "Vapor-Liquid Equilibrium Data for the Propane-Methanol-C02 System", Fluid Phase Equilibria, 28, 73-85... 

Schwartzentruber J., F. Galivel-Solastiuk and H. Renon, "Representation of the Vapor-Liquid Equilibrium of the Ternary System Carbon Dioxide-Propane-Methanol and its Binaries with a Cubic Equation of State. A new Mixing Rule", Fluid Phase Equilibria, 38,217-226 (1987). 

At the end of six hours, the ethane/propane is vented and a 3 1 chloroform/methanol solution is injected to the system, dissolving the surfactant, water, and unreacted monomer. The polymer, which is insoluble in the chloroform/methanol mixture, is collected by filtration, washed with additional chloroform/ methanol and acetone, dried under vacuum, and weighed. The average molecular weight of the polymer (M ) is measured using static light scattering (see for example (12)] of dilute solutions of the polymer in water. 

Figure 3,4.4. VLE correlation of the propane and methanol binary system at 313 K with the IPVDW mixing rule and the PRSV equation of state symbols are the experimental data. A binary interaction parameter k i = 0.0451 was used. (Points are the data of Galivel-Solastiotik et al. 1986 the data file for this system on the accompanying disk is PM313.DAT.)...

Vegetable oils (such as rapeseed, soybean and palm oils) or animal fats (beef tallow) are used for the production of so-called biodiesel, which is typically made by alcoholysis of oils and fats with methanol, ethanol or propan-l-ol. With the growth in the hydrocarbon chain length of the alcohol, the lipophilicity increases so that the two-phase system does not form in the reaction with propan-l-ol, and glycerol does not separate. Therefore, the industrially important esters, such as propyl or butyl esters as well as esters of secondary alcohols, can be only prepared by direct esterification of fatty acids with the appropriate alcohol. Methyl and especially ethyl esters can also be obtained by enzyme-catalysed alcoholysis using non-specific lipases. 

Historically, formaldehyde has been and continues to be manufactured from methanol. EoUowing World War II, however, as much as 20% of the formaldehyde produced in the United States was made by the vapor-phase, noncatalytic oxidation of propane and butanes (72). This nonselective oxidation process produces a broad spectmm of coproducts (73) which requites a complex cosdy separation system (74). Hence, the methanol process is preferred. The methanol raw material is normally produced from synthesis gas that is produced from methane. 

Commercial VPO of propane—butane mixtures was in operation at Celanese Chemical Co. plants in Texas and/or Canada from the 1940s to the 1970s. The principal primary products were acetaldehyde, formaldehyde, methanol, and acetone. The process was mn at low hydrocarbon conversion (3—10%) and a pressure in excess of 790 kPa (7.8 atm). These operations were discontinued because of various economic factors, mainly the energy-intensive purification system required to separate the complex product streams. 

B. Polymeric Urea [Benzene, diethenyl-, polymer with ethenylbenzene, [[[[(1 methylethyl)amino]carbonyt]amino]methyl] deriv.] A 10.0-g. portion of benzylamine polymer beads prepared as in Part A and 125 ml. of tetrahydrofuran (Note 6) are combined in a 300-ml., three-necked, round-bottomed flask equipped with a magnetic stirrer, a dropping funnel, and a condenser fitted with a gas-inlet tube A nitrogen atmosphere is established in the system, and the slurry is stirred while 1.35 g. (0.0159 mole) of isopropyl isocyanate [Propane, 2-isocyanato-] is added. This causes an exothermic reaction, which subsides after about 20 minutes. The mixture is then stirred at room temperature for 22 hours and at reflux for an additional 4 hours. The beads are collected by filtration, washed with 150-ml. portions of tetrahydrofuran (Note 6) and methanol, and dried under reduced pressure over calcium chloride to yield 9.09 g, of the isopropyl urea polymer. 

Methylene chloride is probably the most generally used solvent for decaffeination processes, but others, some of which are already found in small amounts in coffee beans, are coming into use. For example, ethyl acetate,8 formaldehyde-dimethylacetal, ethanol, methanol, acetone,9 propane,10 benzyl alcohol,11 carbon dioxide,12 and supercritical carbon dioxide with an acid13 are used. Generally the pressure and temperature of the system are adjusted to keep the solvent in the liquid state. Coffee oil itself is even described for this use in one patent.14... 

Two types of addition to pyrimidine bases appear to exist. The first, the formation of pyrimidine photohydrates, has been the subject of a detailed review.251 Results suggest that two reactive species may be involved in the photohydration of 1,3-dimethyluracil.252 A recent example of this type of addition is to be found in 6-azacytosine (308) which forms a photohydration product (309) analogous to that found in cytosine.253 The second type of addition proceeds via radical intermediates and is illustrated by the addition of propan-2-ol to the trimethylcytosine 310 to give the alcohol 311 and the dihydro derivative 312.254 The same adduct is formed by a di-tert-butyl peroxide-initiated free radical reaction. Numerous other photoreactions involving the formation by hydrogen abstraction of hydroxyalkyl radicals and their subsequent addition to heterocycles have been reported. Systems studied include 3-aminopyrido[4,3-c]us-triazine,255 02,2 -anhydrouri-dine,256 and sym-triazolo[4,3-fe]pyridazine.257 The photoaddition of alcohols to purines is also a well-documented transformation. The stereospecific addition of methanol to the purine 313, for example, is an important step in the synthesis of coformycin.258 These reactions are frequently more... 

Ng, H.-J. Robinson, D.B. (1985). Hydrate Formation in Systems Containing Methane, Ethane, Propane, Carbon Dioxide or Hydrogen Sulfide in the Presence of Methanol. Fluid Phase Equilibria, 21, 145-155. 

The present chapter will primarily focus on oxidation reactions over supported vanadia catalysts because of the widespread applications of these interesting catalytic materials.5 6,22 24 Although this article is limited to well-defined supported vanadia catalysts, the supported vanadia catalysts are model catalyst systems that are also representative of other supported metal oxide catalysts employed in oxidation reactions (e.g., Mo, Cr, Re, etc.).25 26 The key chemical probe reaction to be employed in this chapter will be methanol oxidation to formaldehyde, but other oxidation reactions will also be discussed (methane oxidation to formaldehyde, propane oxidation to propylene, butane oxidation to maleic anhydride, CO oxidation to C02, S02 oxidation to S03 and the selective catalytic reduction of NOx with NH3 to N2 and H20). This chapter will combine the molecular structural and reactivity information of well-defined supported vanadia catalysts in order to develop the molecular structure-reactivity relationships for these oxidation catalysts. The molecular structure-reactivity relationships represent the molecular ingredients required for the molecular engineering of supported metal oxide catalysts. 

With perfluorobenzoic acid, the attempted replacement of one fluorine by methanethiol in the ethylene glycol/pyridine system resulted in a 60% yield of a 4-methylsulfanyl-substituted product in which the carboxy group is replaced by hydrogen.38 However, in methanol (16 h reflux, with NaOMe). tetrafluoro-4-(mcthylsulfanyl)benzoic acid was obtained in 83% yield,43 and in refluxing propan-2-ol, tetrafluoro-4-(methylsulfanyl)benzenemethanol was obtained in 73% yield.44... 

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