Showing papers on "Raffinate published in 1984"

Serial flow continuous separation process

Abstract: A process for separating an extract component from a raffinate component contained in a feed mixture. A unidirectional fluid flow system is maintained through a series of separating units through which the components travel at different rates. The units are interconnected in series so as to form a single closed loop. A component concentration distribution is established within the system of units so as to comprise a series of zones. Feed and displacement fluid are each mixed with a different intercolumn stream prior to being passed into the inlets of two of the units and extract and raffinate are taken only as portions of streams from outlets of two or more of the units at appropriate points on the component concentration distribution. At the appropriate times the inlets and outlets are shifted so as to simulate movement of the units in a direction downstream with respect to the direction of fluid flow and thereby enable the inlets and outlets to continually lie in the appropriate zones.

Process for the manufacture of lubricating oils

Abstract: The present invention provides for a process for reducing the pour point of a hydrocarbon feedstock containing nitrogen- and sulfur-containing compounds. Specifically, the hydrocarbon feedstock is passed to an extraction zone wherein N-Methyl-2-pyrrolidone is used to extract a portion of the aromatic compounds. A portion of the extraction zone raffinate is then passed to a hydrotreating zone wherein a portion of the nitrogen and sulfur containing compounds are converted to hydrogen sulfide and ammonia. Subsequently, a portion of the hydrotreating zone effluent is then passed to a dewaxing zone and contacted with a shape selective molecular sieve containing dewaxing catalyst.

Selective extraction solvent recovery using regenerated cellulose under reverse osmosis conditions

Abstract: Selective extraction solvents such as NMP, phenol or furfural employed for the extraction of specialty oils, i.e. lubricating, transformer and insulating oils, to remove undesirable aromatic components therefrom, is itself recovered from the extract stream and/or raffinate streams by preferential ultrafiltration through selective membranes of regenerated cellulose. The extract stream, because of its higher solvent content, is the preferred stream for solvent recovery treatment by the reverse osmosis membrane permeation technique. Solvent recovery employing membrane permeation exhibits the advantage of not being energy intensive as is distillation or stripping. The solvent is recovered at a high enough flux rate and at a high enough level of purity to be introduced back into the solvent extraction process optionally at some point in the process wherein the composition of the recovered solvent approximately matches the composition of the solvent present in the process at the point of introduction.

Process for the preparation of liquid 2-hydroxy-methylthiobutyric acid

Abstract: PROCESS FOR THE PREPARATION OF Abstract of the Disclosure A process for the preparation of 2-hydroxy-4-methylthiobutyric acid is disclosed. 2-Hydroxy-4-methylthiobutyronitrile is hydrolyzed with mineral acid to produce an aqueous hydrolyzate containing 2-hydroxy-4-methylthiobutyric acid and substantially free of unreacted 2-hydroxy-4-methylthiobutyronitrile and 2-hydroxy-4-methylthiobutyramide. 2-Hydroxy-4-methylthiobutyric acid is recovered from the hydrolyzate by extraction. Extraction may be carried out without prior separation from the hydrolyzate solution of any substantial fraction of solids present therein, and 2-hydroxy-4-methylthiobutyric acid may be recovered from the extract by steam distillation. The extraction solvent has a boiling point of between about 60°C and about 200°C, and the distribution coefficients for 2-hydroxy-4-methylthiobutyric acid between extract and raffinate, and between extract specimen and wash water, favor transfer to and retention of the acid product in the organic phase.

Adhesive system for use in preparing membrane elements for extraction solvent recovery processes

Abstract: In fabricating membrane elements, and especially spiral wound membrane elements, for the separation of extraction solvents, especially N-methyl-2-pyrrolidone (NMP) from extracted oil fractions (e.g., extract of raffinate), adhesive systems consisting of specific silicone elastomers in combination with specific primers have been identified which are useful in forming the bonds necessary to produce an element, as for example, in forming the edge-seal bonds of the membrane that is used to effect the separation, in bonding the membrane leaves to the metal or plastic components of the element, and in forming a protective outer-wrap for the element.

Some characteristics of liquid membrane with tri-n-octylamine.

Abstract: The characteristics of the liquid membrane with tri-w-octylamine were elucidated. This liquid membrane spontaneously concentrates metals without controlling the concentrations of the agent which provides the driving force to the uphill transport of metals. The rate of iron permeation through the liquid membrane is dependent on the diffusional resistances in two aqueous phases, the diffusional resistance in the membrane phase, and the interfacial resistances. When the acid concentration in the aqueous raffinate phase is large, the interfacial resistances are negligibly small, and the diffusional resistance in the membrane phase is also negligibly small at high amine concentration in the membrane phase. In this case, the permeation rate is controlled only by the diffusional resistance in the raffinate phase.

SEPARATION OF METALS BY LIQUID MEMBRANE WITH TRI-n-OCTYLAMINE

Abstract: The separation of iron and zinc was studied with the use of liquid membrane containing tri-n-octylamine in benzene. The selective separation of zinc and iron can be performed with the help of the strong difference in permeation rates between the two metals. Simultaneous enrichment of zinc and iron can be realized if a proper condition is selected, i.e., the condition that fluxes of both zinc and iron are controlled by the diffusional resistance in the raffinate aqueous phase.

Process for separating zirconium isotopes

Abstract: A solvent extraction-exchange process for the enrichment of either the zirconium 90 isotope component or the zirconium 91-96 isotope component of an aqueous feed stream containing both components is described. An aqueous feed stream of zirconium complexes such as that from a thiocyanate separation process is contacted with an organic solvent to preferentially extract one of the isotope components, resulting in an aqueous raffinate enriched in the other isotope component. The organic phase is further contacted with an aqueous phase enriched in said one isotope component to exchange the other isotope component from the organic phase with the one isotope component in the aqueous phase and produce a further enriched organic phase. The one isotope component in the further enriched organic phase is then stripped with an aqueous acidic strip medium, and zirconium enriched in said one isotope component separated therefrom.

Process for obtaining laxative compounds from senna drugs

Abstract: The present invention provides a process for obtaining laxative compounds from senna drug, wherein (a) the senna drug is extracted with aqueous methanol by countercurrent percolation and the extract concentrated at a temperature of ≦50° C. until the methanol has been completely removed from the extract; (b) the extract obtained is purified by continuous liquid-liquid extraction with an organic solvent; (c) the refined material (raffinate) obtained is transferred to a crystallization apparatus, acidified, while stirring, to a pH of 1.5 to 2.0, seeded with sennoside crystals, left to crystallize while stirring and the crystalline crude sennoside obtained separated off; (d) whereafter, the crude sennoside are, if desired, recrystallized and optionally converted with a pharmacologically compatible base into a pharmacologically compatible salt.

Process for producing aromatic amine

Abstract: A process for producing an aromatic amine from an aromatic halide and ammonia, characterized by comprising the following steps (1), (2) and (3): step (1): reacting the aromatic halide with ammonia in the presence of water by using a catalyst comprising a copper compound as the main constituent, step (2): extracting the aromatic amine from the reaction mixture obtained in step (1) without depositing or separating the copper component contained in the reaction mixture, and step (3): adding an alkali metal hydroxide and/or an alkaline earth metal hydroxide to the raffinate aqueous solution obtained by the extraction procedure in step (2) to deposit copper compounds and separating the same. This process is good in reaction efficiency and permits easy recovery of the catalyst. In the process described above, the extraction of the desired product can be made more effective by incorporating, before step (2), a step of adding to the reaction mixture obtained in step (1) an alkali metal hydroxide and/or an alkaline earth metal hydroxide in an amount of 0.05 to 1 gram equivalent per gram ion of halogen ions contained in said mixture.

Refining of palm oils

Abstract: A palm oil or palm oil fraction is purified by a process involving the solvent extraction of the oil with an alcohol, optionally in admixture with up to 25% water, and a subsequent alkali wash and/or bleaching of the raffinate or an oil derived therefrom. The preferred solvents are azeotropic mixtures of ethanol or isopropanol with water. The refining of difficultly refinable fractions, such as palm oil stearins, is significantly facilitated by the alkali wash of the raffinate.

Process for recovering copper and molybdenum from low grade copper concentrates

Abstract: Low grade copper concentrates containing molybdenum are roasted under conditions to form copper and molybdenum compounds which are soluble in dilute sulfuric acid solutions. Molybdenum is then recovered by solvent extraction from these solutions and further precipitated as ammonium molybdate, while copper can be electrowinned or precipitated from the raffinate. Overall recovery efficiencies are 96% for copper and 84% for molybdenum.

Removal of phenols from water

Abstract: In a process for purification of wastewater streams containing phenolic impurities wherein the wastewater stream is contacted with an ether extraction solvent for the extractive removal of the phenolic impurities, to form an ether extract phase containing at least a portion of the phenolic impurities and an aqueous raffinate phase depleted in the phenolic impurities, the improvement which comprises effecting the separation of the phases in the presence of a phase separation promoting amount of at least one polyhydric alcohol.

Method of extraction of form labile fluid masses

Abstract: 1. Process for the extraction of form-labile, flowable masses by means of high pressure extraction with a liquefied or supercritical gas, characterised in that one conveys the flowable mass and the extraction gas to a mixing chamber , the length of which is a multiple of its breadth or of its diameter and which does not have stirring means, at one end with thorough mixing up and removes from the opposite end, separates the extract-containing gas in a separation step by lowering the density and removes extract and raffinate.

Chromatographic separation of dextrose from starch hydrolysate

Abstract: A process for chromatographic separation of dextrose from starch hydrolysate wherein the aqueous raffinate produced by contacting the starch hydrolysate with a chromatographic column or bed is treated with glucoamylase and recycled, at least in part, for use as an eluant for dextrose. An immobilized glucoamylase is used in the treatment to produce an aqueous dextrose-containing solution. It is this solution that is recycled and used, at least in part, as the eluant in the chromatographic column or bed used in the process.

Process for separating fatty and rosin acids from unsaponifiables

Abstract: A process for separating a fatty and/or rosin acid from an unsaponifiable compound. A feedstream comprising the acids and unsaponifiable compound is contacted with an aqueous alcohol solvent which is selective for and absorbs the fatty and/or rosin acid. An extract stream comprising the solvent and acids, and a raffinate stream comprising the unsaponifiable compound may then be recovered. The feedstock is best used in a diluent which is preferably a hydrocarbon.

Separation and recovery of 3,5-xylenol

Abstract: PURPOSE:To adsorb and separate the titled compound useful as an intermediate of agricultural chemicals, from a mixture containing xylenol isomers, in high purity, an using an adsorbent comprising a faujasite-type zeolite containing silver and/or copper as a cation component. CONSTITUTION:A faujasite-type zeolite containing silver and/or copper as the cation component is used as the adsorbent for the adsorptive separation and recovery of 3,5-xylenol from a mixture containing xylenols. The objective compound can be recovered in high purity as a raffinate component without contamination, even if the starting mixture contains ethylphenol having little boiling point difference between the objective compound. The faujasite-type zeolite is a crystalline aluminosilicate of formula (M is cation, usually Na; n is atomic valence of M; x is 2.5+ or -0.5 for X-type zeolite and 3-6 for Y-type zeolite; y depends upon the degree of hydration).

Preparation of membrane elements for extraction solvent recovery processes

Abstract: In fabricating membrane elements, and especially spiral wound membrane elements, for the separation of extraction solvents, especially N-methyl-2-pyrrolidone (NMP) from extracted oil fractions (e.g., extract of raffinate), adhesive systems consisting of specific silicone elastomers in combination with specific primers have been identified which are useful in forming the bonds necessary to produce an element, as for example, in forming the edge-seal bonds of the membrane that is used to effect the separation, in bonding the membrane leaves to the metal or plastic components of the element, and in forming a protective outer-wrap for the element.

Control of an aromatic extraction

Abstract: In an aromatic extraction process, the flow rate of aromatics to the extraction column is utilized to control the downstream stripping column so as to maintain a desired purity of the aromatic extract stream withdrawn from the stripping column. Also, the flow rate of solvent to the extraction column is manipulated so as to maintain a desired aromatic concentration in the raffinate stream withdrawn from the extraction column. This control, together with other interactive control functions, results in a control of the aromatic extraction process which substantially maximizes the profitability of the extraction process.

Separation of solvent in raffinate and/or back extraction liquid in solvent extraction method

Abstract: PURPOSE:To recover easily solvent in a high yield by washing the raffinate after extraction of the solvent with carbon tetrachloride. CONSTITUTION:The raffinate obtd. by subjecting an aq. soln. to be treated to an extraction treatment using TBP, etc. as a solvent is washed by CCl4. The solvent-contg. CCl4 is then separated from the raffinate and is distilled under an atmospheric pressure or reduced pressure whereby the solvent and the CCl4 are fractionated. The distillation residue obtd. after removal of CCl4 is further fed to a refining stage according to need where the residue is fractionated to pure CCl4 and a pure solvent. The solvent is thus quickly and efficiently recovered.

Separation of picoline isomers

Abstract: A process for separating alpha or gamma-picoline from a feed mixture comprising alpha-picoline or gamma-picoline and at least one other picoline isomer from which the alpha or gamma isomer is to be separated. The feed mixture is contacted at adsorption conditions with an adsorbent comprising a type Y zeolite having alkaline earth or iron group cations at exchangeable cationic sites, which exclude the alpha isomer, or with a potassium exchanged type X zeolite or calcium exchanged type Y zeolite which are selective for the gamma isomer. The high purity alpha or gamma isomer is recovered as a raffinate or extract product, respectively. Pyridine is a preferred desorbent material.