Abstract: A hydrocarbon is removed from an azeotropic mixture of a hydrocarbon and an alcohol by distillation with anhydrous ammonia.

Abstract: Crude 2-methyleneglutaronitrile containing as impurities a metal halide, a trialkylamine, and the trimer or a higher polymer of acrylonitrile can be effectively purified by treating the crude 2-methyleneglutaronitrile with hydrochloric acid, sulfuric acid or nitric acid of a concentration of 1 to 30% by weight and then subjecting the treated methyleneglutaronitrile to vacuum distillation.

Abstract: A process for producing an unsaturated nitrile with saved energy by which the bottom stream from a recovery column is used as the heat source for at least one distillation column in the process and thereafter used to pre-heat a recovery column feed withdrawn from the bottom of an absorption column, characterized in that the bottom stream of the absorption column is previously heated by at least one source of waste heat in the process, the source being selected from (1) the circulating water in the quenching column, (2) the overhead vapor of the absorption column, (3) the overhead vapor of a dehydration column and (4) the overhead vapor of a product column.

Abstract: A method for working up residues of an extractive distilling process for obtaining pure hydrocarbons. The residue from an extractive distilling column is fed to the about middle part of a distilling column. The hydrocarbons are distilled and removed at the head of the distilling column and the solvent is removed at the bottom of the distilling column. A sidestream is removed from the distilling column at a position above the feed plate for the residue from the extractive distilling column via a so-called reflux evaporator plate having an elevated level of liquid. The sidestream is heated by indirect heat exchange with the solvent flowing from the distilling column. The heated-up sidestream is fed back into the distilling column at a level at or above the reflux evaporator plate. The concentration of the solvent at the reflux evaporator plate is controlled by the amount of reflux at the head of the distilling column.

Abstract: A method is disclosed for preventing the condensation of aluminum chloride (AlCl.sub.3) in a fractional distillation column which is operated to separate a fraction which does not include AlCl.sub.3 from a mixture containing AlCl.sub.3 and other metal chlorides and which is operated at temperatures which include the sublimation or melting points of AlCl.sub.3 at the operating pressure of the column. According to this method, titanium tetrachloride (TiCl.sub.4) is maintained in the column in an amount at least as great, by weight, as the amount of AlCl.sub.3 contained in the mixture.

Abstract: A mash column (2) and a rectifying column (4) are used in combination, and impurities contained in mash feed (8) is removed out of the mash column. A salt or salts are added to the top of the rectifying column (4). Alcohol supplied from the mash column (2) is subjected to rectification in the rectifying column (4), and ethyl alcohol is obtained from the top of the rectifying column (4). Bottom products from the rectifying column (4) is concentrated by an evaporator (6) and the concentrated salt or salts solution is recycled to the rectifying column (4). Vapor generated by the evaporator (6) is used as a heat source for the mash column (2).

Abstract: Relatively dry hydrogen iodide can be recovered from a mixture of HI, I.sub.2 and H.sub.2 O. After the composition of the mixture is adjusted so that the amounts of H.sub.2 O and I.sub.2 do not exceed certain maximum limits, subjection of the mixture to superatmospheric pressure in an amount equal to about the vapor pressure of HI at the temperature in question causes distinct liquid phases to appear. One of the liquid phases contains HI and not more than about 1 weight percent water. Often the adjustment in the composition will include the step of vaporization, and the distinct layers appear following the increase in pressure of the vapor mixture. Adjustment in the composition may also include the addition of an extraction agent, such as H.sub.3 PO.sub.4, and even though the adjusted composition mixture contains a significant amount of such an agent, the creation of the distinct liquid phases is not adversely affected.

Abstract: A process for separating acetonitrile from a crude olefinically unsaturated nitrile which comprises passing a reaction gas obtained in the ammoxidation of propylene or isobutylene through a quenching column, an absorption column with water, an extractive distillation column for the olefinically unsaturated nitrile and a stripping column for acetonitrile successively, condensing the acetonitrile-containing vapor from the top of the stripping column, evaporating the condensate acetonitrile-containing liquid into a gas, subjecting the resulting gas mixture to a vapor-liquid separation and subjecting the gas separated to an incineration while withdrawing the liquid separated.

Abstract: A process for isolating 1,3-butadiene by means of a selective solvent from a C.sub.4 -hydrocarbon mixture which contains 1,3-butadiene, propyne, hydrocarbons which are more soluble than 1,3-butadiene in the selective solvent and hydrocarbons which are less soluble than 1,3-butadiene in the selective solvent, wherein the C.sub.4 -hydrocarbon mixture is separated, using one or more extractive distillation zones, into a distillate containing the less soluble hydrocarbons, a stream of 1,3-butadiene and a stream containing the more soluble hydrocarbons, and the propyne is separated off either by distillation of the C.sub.

Abstract: An aqueous solution of acrylic acid and water containing 30 wt. % or less acrylic acid, can be concentrated to 40-60 wt. % acrylic acid in the overhead of a distillation column through the addition of certain salts that reverse the relative volatility between acrylic acid and water. Suitable salts can be ferrous, lithium and calcium chlorides.

Abstract: A process for the production of anhydrous or substantially anhydrous formic acid by hydrolysis of methyl formate which is carried out in a column having an upper fractionating section, a middle hydrolysis section and a lower extraction section and in which(a) the hydrolysis is carried out in the middle section of the columm, with water and methyl formate in countercurrent,(b) the resulting formic acid is extracted, in the lower section of the column, by means of a carboxylic acid amide which is fed into the lower end of the middle section of the column,(c) the extract phase, consisting in the main of formic acid and the carboxylic acid amide, is distillatively dehydrated, or substantially dehydrated, in the lower section of the column,(d) the methanol and uncovered methyl formate are removed by fractional distillation in the upper section of the column and(e) the pure formic acid or concentrated aqueous formic acid is distilled from the anhydrous or substantially anhydrous extract phase in a second column, le

Abstract: A crude olefin oxide containing high-boiling ingredients is distilled at a pH of 4 to 7 in the presence of a nonvolatile neutral or weakly basic alkali metal or alkaline earth metal salt or hydroxide to separate the olefin oxide from the high-boiling ingredients. This permits the prevention of the polymerization of the olefin oxide and its conversion to the corresponding glycol.

Abstract: A method of inhibiting the polymerization of styrene which comprises mixing with the styrene a minor but effective quantity of an inhibitor compound selected from the group consisting of 2-methylbenzoquinone-4-oxime, 2,3,5-trimethylbenzoquinone-4-oxime and mixtures thereof.

Abstract: According to this invention, there is provided a method of suppressing the rise in surface temperature of the heating tubes in a fractionation apparatus for a crude oil, characterized in that an aqueous solution containing ammonia or ammonium ion is injected into the upstream line of the crude heater in an amount of 1 to 20 ppm in terms of ammonia based on the crude oil.

Abstract: An azeotropic distillation is conducted by feeding a part of an entrainer to the lower region of an azeotropic zone in a distillation column.

Abstract: A method for stabilizing acetylene against explosive decomposition comprising mixing together with the acetylene a chemical free radical scavenging agent chosen from the group consisting of nitric oxide, hydrogen chloride, hydrogen bromine, hydrogen iodide and vinyl bromine as well as mixtures thereof.

Abstract: A process for recovering substantially dry methyl chloride from a stream of wet methyl chloride by distilling the wet methyl chloride in the presence of at least 10 molar % hydrogen chloride based on the hydrogen chloride, methyl chloride and water being distilled. The distillation is carried out under super atmospheric pressure and a temperature to produce an aqueous hydrochloric acid of less than 36 wt %, and preferably under such super atmospheric pressure and sufficient temperature to produce an azeotropic hydrochloric acid containing a low concentration of hydrogen chloride. Increasing pressures allows increasing temperatures in the bottoms which form azeotropes of lower concentration hydrochloric acid. The resulting overhead of such a distillation, methyl chloride-hydrogen chloride, will contain less than about 400 molar ppm water. When the distillation is carried out in the presence of about 12 to 25 molar % hydrogen chloride, the overhead will contain between about 100 to 400 molar ppm water.

Abstract: A method of recovering fresh water from underground saline water. The method involves the pumping of water vapor from an underground location immediately above a supply of saline water to a condensor where the fresh water is recovered. The heat of condensation released by the vapor during recovery is returned to the underground saline water to raise its temperature and thereby increase its rate of vaporization. Other alternative processes to increase the rate of vaporization include utilization of an external source of waste thermal energy, injection of refrigerant into the underground saline water, and in those structures where petroleum residues may be simultaneously and profitably recovered with the fresh water, the injection of refrigerants soluble in petroleum into the underground saline water.

Abstract: Phosphate and phosphite mono- and di-esters and thioesters in small amounts function as antifoulant additives in overhead vacuum distilled gas oils employed as feedstocks in hydrodesulfurizing wherein such feedstocks are subjected to elevated temperatures of from about 200.degree. to 700.degree. F and which are prone under such processing to produce material that deposits and accumulates upon the surfaces of hydrodesulfurization catalysts and also equipment, such as heat transfer surfaces and the like. Such additives not only inhibit and suppress fouling but also reduce fouling in previously fouled such systems.

Abstract: Thio-phosphate and -phosphite mono- and di-esters in small amounts function as antifoulant additives in crude oil systems employed as feedstocks in petroleum refining which are subjected to elevated temperatures of from about 100.degree. to 1500.degree. F and which are prone to produce material that deposits and accumulates upon the surfaces of petroleum processing equipment, such as heat transfer equipment and the like. Such additives not only inhibit and suppress fouling but also reduce fouling in previously fouled refining systems.

Abstract: Phosphate and phosphite mono- and di-esters in small amounts function as antifoulant additives in crude oil systems employed as feedstocks in petroleum refining which are subjected to elevated temperatures of from about 100.degree. to 1500.degree. F. and which are prone to produce material that deposits and accumulates upon the surfaces of petroleum processing equipment, such as heat transfer equipment and the like. Such additives not only inhibit and suppress fouling but also reduce fouling in previously fouled refining systems.