Abstract: Ethylene glycol esters or propylene glycol esters are recovered from their mixtures with high- and low-boiling organo-halogens by (1) distilling the mixture in a first distillation zone to form a first bottoms stream comprising the high-boiling organo-halogen impurities and a first overhead stream comprising the ethylene glycol esters or propylene glycol esters together with the low-boiling organo-halogen impurities, and (2) distilling at least a portion of the first overhead stream in a second distillation zone to form a second overhead stream containing the low-boiling organo-halogen impurities and a second bottoms stream comprising the desired ethylene glycol esters or propylene glycol esters having a substantially reduced concentration of the organo-halogen impurities.

Abstract: Impurities such as hydrogen sulfide and carbon dioxide are removed from fluids such as natural gas, synthesis gas or liquid or gaseous hydrocarbons by contact with an aqueous alkanolamine solution which absorbs said impurities from the fluid. The resultant spent impurity-enriched absorbent amine stream containing the absorbed impurities is split into two streams; one stream being routed directly to the top of an amine regenerator column and the second stream being routed to a heat exchanger where it is heated en route to an intermediate point of the regenerator column by heat exchange with the hot regenerated solution coming from the bottom of the regenerator column. The spent amine stream which is passed without prior heating directly to the top of the regenerator column is heated by condensing steam in the column which would normally escape therefrom, thereby reducing the amount of "saturation" steam which is lost from the system.

Abstract: The double effect floating solar still uses a partly immersed corrugated metal plate to heat the upper layer of a body of water in order to establish a temperature difference between the upper and lower sections of the still. The difference in temperature creates a difference in vapor pressures, forcing the vapor produced in the hot section of the still to flow into a submerged condenser, giving up the heat of condensation to the surrounding water, preheating it before it reaches the stage of evaporation.

Abstract: Ethylene glycol or 1,2-propylene glycol contained in mixtures with lower carboxylate esters of glycol, e.g. as produced by hydrolysis of the esters, is recovered by distillation of the mixtures with a hydrocarbon forming a minimum boiling azeotrope with the ethylene dlycol or 1,2-propylene glycol, the hydrocarbon being maintained in an inert atmosphere in the system.

Abstract: A methanol production process including synthesis gas generation, methanol synthesis and methanol distillation includes an autonomous system in which low pressure steam is raised by heat exchange with a fluid stream at 120.degree.-300.degree. C. in the process, the low pressure steam is used as live steam to heat at least distillation column in the distillation section and bottoms water from a distillation column in that section is used as feed to the autonomous steam system.

Abstract: Methyl t-butyl ether may be recovered from etherification reaction effluent by extractive distillation in the presence of n-butanol.

Abstract: The invention provides unusally efficient distillation apparatus configured into a compact structure which conserves material in its construction and power consumption in its operation. The present structure particularly provides horizontally disposed flash effect distillation chambers coupled "back-to-back" across a common wall, the chambers being operable as a distillation system for water purification and/or solute concentration or as a sub-system in multi-effect distillation systems.

Abstract: In an oxidation process for converting methacrolein to methacrylic acid, methacrylic acid is recovered by cooling and condensing the effluent from the oxidation, followed by azeotropic distillation of the condensate with a suitable solvent, such as methyl n-propyl ketone. The condensed effluent contains methacrylic acid and water as the major components along with by-product acetic acid, a minor amount of unreacted methacrolein and impurities. Substantially dry crude methacrylic acid is separated as a bottom product from the azeotropic distillation and an azeotrope of water and the solvent is taken overhead and condensed. After condensation, solvent-rich and water-rich phases form and are separated. The solvent-rich phase is returned to the distillation column as a reflux, while the water-rich phase is sent to a stripping column for recovery of residual solvent. Water is withdrawn from the bottom of the stripping column and recycled or discarded, as desired.

Abstract: Methyl tertiary butyl ether may be recovered from etherification reaction effluent by azeotropic distillation to recover methanol-ether azeotrope overhead which is water-washed to give pure ether raffinate plus ether-methanol bottoms, the latter being azeotropically distilled to yield ether-methanol overhead which is recycled to water-washing.

Abstract: A lower carboxylic acid such as acetic acid is separated and recovered from an aqueous medium by the steps which include contacting, in an extraction zone, the aqueous medium with an extracting agent such as trioctyl phosphine oxide dissolved in an organic solvent such as a mixture of paraffins having a boiling range of about 160.degree. C. to 175.degree. C.

Abstract: A method for separating and purifying methacrylic acid is disclosed in which an aqueous solution (A) of methacrylic acid containing acetic acid is brought into contact under counter-current flow with a mixed solvent (B) of methyl methacrylate and toluene in a ratio of from 3 : 2 to 1 : 9 by weight, to extract substantially the whole amount of methacrylic acid in solution (A) into mixed solvent (B); after which the methacrylic acid is separated and purified by distillation.

Abstract: A solar still includes a pair of parallel dikes separated by a ditch, a first sheet overlying the ditch and pair of parallel dikes, the sheet having a pair of edges arranged substantially parallel to, and outside, the dikes, and a second sheet overlying the first sheet, the second sheet having a pair of edges bonded together with the edges of the first sheet to form a water vapor-impervious seal.A plurality of vertical columnar supports are periodically positioned in spaced relation between the first and second sheets in the center of the ditch to maintain the second sheet in spaced relation above the first sheet. The second sheet has a ridge coincident with the supports and filamentary members which connect the tops of the supports, and angularly slopes on either side thereof toward the outer edges of the dike.

Abstract: Propylene oxide is separated from contaminating quantities of methanol and acetone by extractive distillation with water.

Abstract: The thermal efficiency of an ammonia still is significantly increased by the use, in conjunction with the usual countercurrent steam stripping medium, of an auxiliary inert gas stripping medium initially heated and humidified by heat exchange with hot still bottoms derived from the still.

Abstract: Treatment of liquid waste contaminated with volatile radioactive substances under both acid and alkaline conditions in a single unit consisting of a still with connecting superposed column of spaced bubble-cap type plates. The pH of the liquid in the still is different from the pH of liquid reflux in an intermediate group of plates in the column facilitating scrubbing out of the volatile radioactive substances. An intermediate loop for circulating liquid from the bottom plate of the intermediate group to the top plate of the intermediate group at controlled pH is provided for this purpose.

Abstract: Desalination apparatus utilizing solar heating of metal member(s) such as balls, rollers, or metal endless belt(s) in a heating chamber and vaporizing saline water with the latent heat in said metal member(s) by spraying saline water thereon in a vaporizing chamber, a water-cooled condenser to condense the vapors, a trough to collect the condensate, a rinse tank to remove salt deposits and/or saline water from the metal member(s), and means for returning the rinsed metal member(s) for solar reheating.

Abstract: The process of separating water and wash oil from a gaseous feed stream of water vapor, wash oil and light oil involving (a) directing the gaseous feed stream in an upward direction and in contact with a cooling solid surface such that a temperature gradient of the gaseous stream is produced such that the temperature of the gaseous stream is highest at the bottom of the cooling solid surface such that gaseous components of the gaseous stream having the highest boiling temperature condense onto the lower portions of the cooling solid surface and wherein the lower boiling components of the gaseous stream condense onto the solid surface at higher portions on the solid surface to thereby form a liquid film on the solid surface, which film then runs downward onto the lower portions of the solid surface to thereby inhibit deposits from adhering to these lower portions of the solid surface; (b) withdrawing a gaseous stream containing a major portion of light oil; and (c) withdrawing a liquid condensate which contain

Abstract: A process for separating two close-boiling chemical compounds by fractionation wherein the bottoms liquid stream removed from the fractionation column is flashed to produce cool liquid which is then used to condense overhead vapors of the column. The column is reboiled by vapor derived from the flashed bottoms liquid stream and which has been heated by compression in a heat pump.

Abstract: Desalination apparatus using solar energy comprises a main insulated container with a subsidiary preheating container next to it; the main container is covered with a transparent cover serving as a selective filter to provide "the greenhouse effect" and also as a condensation surface for water vapor, and this transparent cover incorporates a hollow space, for example by making the cover double skinned. The hollow space forms part of a syphon which automatically regulates the water levels, transferring salt water from a preheating container to the main container as the level in the main container falls due to loss by evaporation leading to condensation and withdrawal of the desalinated water. The hollow part of the transparent cover thus serves also to preheat the incoming salt water with the heat lost upon condensation by the vapor within the main container.

Abstract: A process for a separation of hexafluoropropylene oxide from hexafluoropropylene by an extractive distillation in the presence of a normally liquid inert compound such as 1,2-dichloroethane, monochlorobenzene, di-isopropyl ether and 1,1,2-trichloroethane.