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| Number | Title | Issue Date |
| 5718810 | Methanol recovery using extractive distillation A method for recovering methanol from sulfur-based wood pulping process vapors, which contain at least methanol and dimethyl disulfide. The method involves three steps. The first step consists of introducing the vapors into a first distillation tower at a... | 02/17/1998 |
| 5662780 | Process for purifying acetic acid A process for purifying acetic acid which comprises: introducing a feedstock aqueous solution of acetic acid having an acetic acid concentration of from 10 to 50% by weight into an extractor; supplying an extracting medium containing isopropyl acetate in ... | 09/02/1997 |
| 5296104 | Process for obtaining purified aqueous hydrogen peroxide solutions Process for obtaining purified hydrogen peroxide solutions, consisting in evaporating the crude aqueous hydrogen peroxide solution containing the impurities and feeding by means of the vapour phase produced the foot of a distillation column provided in it... | 03/22/1994 |
| 5264117 | Distillation of hydrocarbons Where side stream distillate strippers are used in the distillation of hydrocarbons, the required size of the distillation column and the amount of stripping gas or vapor required are reduced by passing components stripped from the distillates through a p... | 11/23/1993 |
| 5244545 | Process for removing acetone from carbonylation processes Disclosed is an improved process for the removal of acetone from a production system wherein acetic anhydride is produced by contacting a mixture comprising methyl iodide and methyl acetate and/or dimethyl ether with carbon monoxide in the presence of a c... | 09/14/1993 |
| 5124004 | Distillation process for ethanol A method of distillation employing a heat pump (which may be driven by a compressor) using a vapor stream from within the distillation system as a heat source and a liquid stream from within the distillation system as a heat sink. The selection of heat-so... | 06/23/1992 |
| 5106458 | Method for the purification of propylene oxide Methyl formate is removed from impure propylene oxide by contacting the impure propylene oxide in a treating zone with a basic ion exchange resin for a period of time sufficient to convert the methyl formate to formic acid and methanol, and by withdrawing... | 04/21/1992 |
| 5064507 | Distillation process for recovery of high purity phenol High purity phenol is obtained from cleavage of cumene hydroperoxide by treating the crude phenol product stream in a first treatment zone with an amine, a coarse distillation to obtain an overhead stream comprising phenol, alpha-methyl styrene, cumene, a... | 11/12/1991 |
| 5057192 | Acetone removal from acetic anhydride production process Disclosed is an improved process for the removal of acetone from a production system wherein acetic anhydride is produced by contacting a mixture containing methyl iodide and methyl acetate and/or dimethyl ether with carbon monoxide in the presence of a c... | 10/15/1991 |
| 5028735 | Purification and preparation processes for methyl methacrylate A purification process for methyl methacrylate (MMA) and a recovery process for methanol are disclosed. A mixture, which contains water, methanol and methyl methacrylate (MMA) as principal components along with at least one of methyl acrylate, methyl prop... | 07/02/1991 |
| 4902385 | Process for the purifying distillation of crude sec-butyl alcohol Practically anhydrous crude sec-butyl alcohol produced by catalytic direct hydration of n-butenes is freed by means of water from the azeotropically boiling and low-boiling by-products by continuous azeotropic distillation in a separation column, the prep... | 02/20/1990 |
| 4898644 | Removal of volatile acids from aqueous solutions A process for removing volatile acids from aqueous solutions which involves steam stripping a volatile acid from an aqueous solution and contacting the vaporized acid with a reactable cation to form a salt of the acid. A preferred embodiment of apparatus ... | 02/06/1990 |
| 4857151 | Phenol purification Crude phenol containing methyl benzofuran and other impurities is distilled in the presence of water to recover a phenol bottoms having a reduced quantity of impurities. The water-phenol overhead is cooled to separate a water phase essentially free of met... | 08/15/1989 |
| 4851086 | Production of high purity phenol by steam distillation Crude phenol, containing AMS by-product, and MBF impurity, is distilled in the presence of water to separate MBF impurity.... | 07/25/1989 |
| 4744869 | Process for purifying methanol A process for purifying methanol which comprises introducing crude synthetic methanol obtained by catalytic reaction of carbon oxide and hydrogen into a rectifying column either as such or after it is first introduced into a topping column and distilled w... | 05/17/1988 |
| 4740273 | Process for the purification of diethoxymethane from a mixture with ethanol and water A process for purifying diethoxymethane from a mixture containing ethanol and, optionally, water. The process involves the addition of an amount of water, DEM, or an appropriate mixture of any two or three of water, DEM and ethanol that is effective in mo... | 04/26/1988 |
| 4566947 | Method of separating a mixed liquid into light and heavy fractions by distillation A two-stage distillation method for separating a mixed liquid such as a dimethylformamide-containing aqueous liquid or a methanol-containing aqueous liquid, into light and heavy fractions. The mixed liquid is first subjected to a distillation treatment in... | 01/28/1986 |
| 4532012 | Production of high purity phenol by distillation with steam and a solvent Phenol containing MBF impurity is distilled in the presence of water and an extraction solvent for MBF (preferably AMS and/or cumene) to recover a phenol bottoms having reduced impurities. The use of solvent permits a reduction in the amount of water used... | 07/30/1985 |
| 4522920 | Production of ethanol A flow of fermenting liquor from a fermentor is separated into a yeast concentrate flow, which is recirculated to the fermentor, and a yeast-free flow which is separated in a simple evaporator unit into a first ethanol-enriched vapor flow and a first liqu... | 06/11/1985 |
| 4511437 | Process for the continuous rectification of alcoholic fermates A process for continuous rectification of a liquid mixture containing alcohols, particularly a liquid fermate, employs a plurality of distillation columns to which the liquid mixture is fed in parallel, and which have successively reduced operating pressu... | 04/16/1985 |
| 4504364 | Phenol purification In the production of high purity phenol, a water-phenol mixture recovered from the top of a distillation column is contacted with a water immiscible solvent to extract methyl benzofuran and other by-products and impurities in phenol production therefrom, ... | 03/12/1985 |
| 4434029 | Process for producing unsaturated nitrile 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 withdr... | 02/28/1984 |
| 4358536 | Production of ethanol A flow of fermenting liquor from a fermentor is separated into a yeast concentrate flow, which is recirculated to the fermentor, and a yeast-free flow which is separated in a simple evaporator unit into a first ethanol-enriched vapor flow and a first liqu... | 11/09/1982 |
| 4342627 | Dehydration of alcohols The present invention relates to a continuous process for producing substantially anhydrous alcohols from aqueous solutions thereof by distilling a mixture of aqueous alcohol and an entrainer to a drying column withdrawing an azeotrope as a distillate and... | 08/03/1982 |
| 4302298 | Process for isolating methyl tert-butyl ether from the reaction products of methanol with a C4 hydrocarbon cut containing isobutene Process for isolating methyl tert-butyl ether contained in the reaction product of methanol with a C4 hydrocarbon cut containing isobutene, comprising fractionating said reaction product by introducing it at an intermediate point of a distillat... | 11/24/1981 |
| 4238295 | Energy efficient recovery of acrylonitrile Substantial operating cost savings are realized in the recovery of acrylonitrile from an aqueous solution containing acrylonitrile by using the recovery column bottoms stream to provide heat to one or more distillation columns in the process.... | 12/09/1980 |
| 4070254 | Process for preparing a purified methacrylic acid ester A process for preparing a purified methacrylic acid ester from a crude methacrylic acid ester containing an isobutyric acid ester as an impurity, comprising the steps of azeotropically distilling the crude methacrylic acid ester in the presence of water t... | 01/24/1978 |
| 4046641 | Process and apparatus for the separation of crude benzol and naphthalene from washing oil A process and apparatus for the regeneration of washing oil which has been spent to recover naphthalene and/or benzol from coke oven gas. The spent washing oil is stripped by steam in a bubble column arranged as an integral part of a single main column th... | 09/06/1977 |
| 4008130 | Method for distilling a ternary azeotrope of fluorosilicic acid, hydrogen fluoride and water Fluorosilicic acid solutions, which normally undergo decomposition when distilled, thereby creating unwanted forms of SiO2, are rendered stable during distillation by providing in the fluorosilicic acid solution an amount of HF which is at leas... | 02/15/1977 |
| 3960672 | Continuous distillation process for purifying alkanols Pure C1 -C3 alkanols are prepared from crude water containing alcohols in a continuous distillation process which includes an extractive distillation zone into which water and crude alcohols are introduced and from which is removed a... | 06/01/1976 |
| 3940450 | Preparation and recovery of ethers Methyl tertiary butyl ether may be recovered from etherification reaction effluent by azeotropic distillation to recover methanol-ether azeotrope overhead which latter is azeotropically distilled in the presence of n-pentane to give pure ether bottoms sub... | 02/24/1976 |
