Abstract: In a fractional distillation process in which a heating fluid and waste heat stream are utilized to supply heat to a fractional distillation column and in which the heat supplied from the waste heat stream is not controllable, control of the liquid level in the fractional distillation column is accomplished by manipulating the flow rate of the heating fluid so as to maintain a desired liquid level until such time as the flow rate of the heating fluid becomes zero at which time the flow rate of the external reflux to the fractional distillation column is manipulated to maintain a desired liquid level in the fractional distillation column. A switching of control of the liquid level provides a means by which an uncontrollable heat input may be provided to the fractional distillation column without losing control of the liquid level in the fractional distillation column.
Abstract: Disclosed is a method of distilling readily polymerizable vinyl aromatic compounds such as styrene, .alpha.-methyl styrene, vinyl toluenes and divinylbenzenes wherein 2,2-bis(3,5-dinitro-4-hydroxy-phenyl)propane is used as a polymerization inhibitor. The invention is particularly useful for the distillation of divinylbenzene.
Abstract: Process and apparatus for extracting an organic liquid from an organic liquid solute/solvent mixture. The mixture is contacted with a fluid extractant which is at a temperature and pressure to render the extractant a solvent for the solute but not for the solvent. The resulting fluid extract of the solute is then depressurized to give a still feed which is distilled to form still overhead vapors and liquid still bottoms. The enthalpy required to effect this distillation is provided by compressing the still overhead vapors to heat them and indirectly to heat the still feed. The process is particularly suitable for separating mixtures which form azeotropes, e.g., oxygenated hydrocarbon/water mixtures. The energy required in this process is much less than that required to separate such mixtures by conventional distillation techniques.
Abstract: A process permitting hazard free purification by distillation of compounds which are distillable per se but which present the risk of explosive decomposition under the effect of elevated temperatures. A desensitizing substance is added to the compounds to be distilled.Aliphatic alcohols for instance are suitable additives for alkinols.Examples are provided for the distillation of butinediol-1,4 together with the additive glycerin.
Abstract: An apparatus for producing fresh water from sea water in which a vertical accumulator utilizes the sensible heat of sea water so as to evaporate said sea water to a temperature above 100.degree. C. under pressure, a heat-exchanger connecting between the upper and lower portions of said accumulator causes a high temperature liquid to effect heat-exchange with sea water to be evaporated, a fresh sea water feed line connected to the lower portion of said accumulator adjusts the pressure within the accumulator and an evaporator receives higher temperature sea water. The accumulator accumulates heat in such a manner that the upper portion of said accumulator holds higher temperature sea water and the lower portion of the accumulator holds lower temperature sea water so that when heat is accumulated, the amount of said higher temperature sea water increases and when heat is radiated, the amount of higher temperature decreases whereby sea water evaporates at all times.
Abstract: An apparatus unit for the fractional distillation and rectification of liquid mixtures includes a plurality of horizontal superimposed tubular main sections interconnected in series by a plurality of tubular connecting sections, e.g. U-shaped, to define an elongated space along which liquids and vapors flow. Intimate contact between liquids and vapors and efficient heat and mass transfer are provided by a stirrer rotating within the main section about horizontal axes and magnetically driven from the outside. Suitable inlet and outlet ports and heating and cooling devices are provided. An arrangement for joining the adjacent sections without the use of flanges or threaded portions is provided. A number of such units are preferably associated to form a modular apparatus, the individual units being operatively connected as desired to provide series, parallel or mixed flow of the fluids.
Abstract: In a fractional distillation column in which at least a first component and a second component are at least partially separated with the first component being removed principally as an overhead product and the second component being removed principally as a bottoms product and in which the heat supplied to the fractional distillation column is used as the primary control for the overhead product composition with the flow rate of external reflux to the fractional distillation column being used to control the bottoms product composition, a comparison of the actual concentration of the second component in the overhead product to the desired concentration is utilized to bias the control signal which is utilized to manipulate the flow rate of the external reflux to the fractional distillation column.
Abstract: Butenes are added to the methanol-containing methyl-tertiary-butyl ether (MTBE) reactor effluent fractionation to effect recovery of substantially methanol-free MTBE bottoms product. Methanol analysis taken below the fractionator feed locus manipulates control of butenes addition. In an embodiment, the methanol-butenes-containing overhead stream from the fractionation is treated over activated alumina to adsorb methanol, yielding a methanol-free butenes feed for HF alkylation of isobutane. The used adsorbent can be regenerated using hot butenes product and/or MTBE reactor feed vapor with the recovered methanol being recycled to the MTBE reaction.
Abstract: Apparatus for preparation and distillation of low-alcohol-content, fermentation products into high-alcohol-content, fuel-grade product using solar energy to carry out the fermentation and distillation. The apparatus includes a solar collector with reflectors, fermenting tanks, a distillation column, and temperature controls. The working fluid for the solar collector is isolated from the fluid being distilled.
Abstract: A process for the preparation of acetic acid esters CH.sub.3 --CO--O--R.sup.1 (I, R.sup.1 =an organic radical other than methyl and ethyl) by alkali-catalyzed trans-esterification of an acetic acid ester CH.sub.3 --CO--O--R.sup.2 (II, R.sup.2 =methyl or ethyl) with an alcohol R.sup.1 --OH (III), accompanied by elimination of the alcohol R.sup.2 --OH (IV), wherein(a) the trans-esterification reaction is carried out in the middle section K.sub.M of a distillation column K, the alcohol III being fed as liquid into the upper zone and the ester II into the lower zone of K.sub.M,(b) the alkaline catalyst is introduced into the upper part K.sub.U of K,(c) the alcohol IV, or a mixture of IV and the ester II, is taken off the top of the column,(d) the mixture obtained from (c) (unless the alcohol IV alone is obtained) is separated in the column section K.sub.U or in a stripper column K.sub.S into IV and the azeotrope of II and IV, and the latter is recycled to the lower zone of K.sub.
Abstract: A process is disclosed for the recovery of a phenol-free cumene fraction from a mixture thereof with phenol and water. Said mixture is introduced into a first fractionation column at conditions to separate a bottom fraction comprising a major portion of said phenol and an overhead fraction comprising said cumene and water and a residual portion of said phenol. The overhead fraction is condensed to form an aqueous phase containing a minor portion of the residual phenol and a water-saturated organic phase comprising cumene and the balance of said residual phenol. The water-saturated organic phase is then further treated in a second fractionation column whereby cumene is recovered as an overhead fraction substantially free of phenol.
Abstract: A method and apparatus for distilling readily polymerizable liquid such as readily polymerizable monomers without causing the formation of an undesirable polymerization product is disclosed. This distillation is effected by(a) vaporizing the polymerizable liquid from a liquid phase containing the same in an evaporator by externally heating the liquid phase;(b) converting the vapor of the polymerizable liquid to a superheated state by externally heating, and introducing the vapor of the polymerizable liquid to the inlet of a condenser, while the vapor is maintained at the superheated state; and, then,(c) condensing the vapor in the condenser, while a portion of the condensed fraction is circulated to the inlet of the condenser, whereby the condensation surface thereof is wetted.
Abstract: Process for dehydrating aliphatic alcohols admixed with water wherein the alcohols-water mixture is subjected to a first fractionation in the presence of a selective solvent, giving a vapor effluent containing dehydrated light alcohols and a liquid phase containing heavy alcohols, water and the selective solvent, said liquid phase being subjected to a second fractionation giving as vapor effluent an hetero-azeotropic mixture of water and heavy alcohols and, as liquid effluent, the selective solvent, which is fed back, said hetero-azeotropic mixture being condensed and separated into:(a) a light phase of high alcohol content which is subjected to a third fractionation giving a vapor effluent which is fed back and dehydrated heavy alcohols as liquid effluent, and(b) a heavy phase which is subjected to a fourth fractionation giving a vapor effluent which is fed back and water as liquid effluent.
Abstract: In a process for producing a 2-hydroxyalkyl acrylate or methacrylate which comprises esterifying acrylic or methacrylic acid with an alkylene oxide having 2 to 4 carbon atoms in the presence of an esterification catalyst and distilling the resulting reaction mixture in a distillation column, the improvement wherein the vapor of the ester monomer from the distillation column, while being maintained in the superheated state, is introduced into a condenser of the gas-liquid direct contact type whose inner wall corresponding to its gas inlet portion is kept at a temperature below the boiling point of the ester at the operating pressure, to contact it directly with a concurrently flowing spray liquid of the ester-precooled to a temperature below the boiling point of the ester at the operating pressure, whereby said vapor is condensed to a liquid at said temperature below the boiling point of the ester at the operating pressure.
Abstract: A process for the production of alkyl esters of saturated aliphatic carboxylic acids by reacting in an alkoxycarbonylation stage olefins with carbon monoxide and alkanol in the presence of a catalyst consisting of a cobalt compound and a promoter from the group of pyridine, non-ortho-substituted alkylpyridine or mixtures thereof at elevated pressure and elevated temperature. The reaction mixture produced is reprocessed and the pyridine, non-ortho-substituted alkylpyridine, or mixture used as the promoter is rectified prior to its feedback into the alkoxycarbonylation stage in the presence of a given carboxylic acid which is thermally stable under the conditions of reprocessing and which forms a maximum azeotrope with the promoter under the conditions of rectification.
Abstract: A solar energy desalination process utilizing solar radiation directly for the evaporation of salt water is described. Ambient air takes on water vapor as the air passes through an evaporative medium. It is then directed between a saline water-covered, solar absorbing surface and a solar collecting housing. The resulting heated and moisture-saturated air is cooled in a heat exchange means where condensation of fresh water occurs. Simultaneously, cool salt water is utilized as the cooling water in the heat exchange means, and takes on the heat of condensation given up by the condensing vapor. The heated salt water from the heat exchange means is partially directed over the solar absorbing surface, and at least a portion of it is also directed to wet the evaporative medium. Several optional sub-processes are described for operation of the system during periods of reduced insolation, and an alternative process is described for operation of the process on a floating platform.
November 6, 1980
Date of Patent:
December 14, 1982
Institute of Gas Technology
Ahmed A. ElDifrawi, Christopher F. Blazek, Bernard D. Yudow
Abstract: The distillative separation of a mixture of glycerine and glycerine-based acetal or ketal transesterification products is aided by addition of a borate ester-forming compound to the mixture prior to distillation.
Abstract: A method of purification of crude .beta.-phenylethyl alcohol to give a highly pure .beta.-phenylethyl alcohol suitable as a perfume, which comprises subjecting the crude .beta.-phenylethyl alcohol to azeotropic distillation in the presence of an azeotropic solvent selected from water, an alkylene glycol, an alkylene glycol monoalkyl ether and a mixture of two or more kinds of these solvents, or extractive distillation in the presence of an extractive solvent selected from glycerine, an alkylene glycol, a polyalkylene glycol, an alkylene glycol monoalkyl ether, a polyalkylene glycol monoalkyl ether and a mixture of two or more kinds of these solvents.
Abstract: Halogenated hydrocarbon and uncontaminated water is recovered from a stream of process water contaminated with halogenated hydrocarbon and hydrogen halide. The process water is neutralized and then distilled to obtain a first fraction containing halogenated hydrocarbon and water and a second fraction containing uncontaminated water. The first fraction is allowed to settle into layers of halogenated hydrocarbon and water which are then removed.The contaminated stream may be obtained from a process for the solvent dewaxing of a petroleum fraction.
Abstract: The separation of mixtures of hexafluoropropylene oxide and hexafluoropropylene is effected by extractive distillation in the presence of methylene chloride, whereby an excellent separating effect is achieved at a low energy consumption.