Abstract: Monosaccharides such as glucose solution are catalytically hydrogenated in fixed bed reaction process using a high activity nickel catalyst to produce at least about 98 W % conversion to sorbitol solution. The feedstream pH is controlled to between 7 and 13 by adding a basic solution such as sodium hydroxide. Reaction zone conditions are 500-2000 psig hydrogen partial pressure, 130.degree.-180.degree. C. temperature, and use a ratio of hydrogen gas/feed liquid within the range of 1000-5000. Feedstream liquid space velocity is within range of 0.5-3.5 Vf/Hr/Vc.
Abstract: This invention relates to an improved process for the preparation of a mixture of various low molecular weight hydroxyaldehydes, hydroxyketones and polyhydric alcohols by the condensation of formaldehyde with itself. The essential feature of the improvement is that unpurified synthesis gases of the kind obtained from the large scale industrial production of formaldehyde can be used directly as the source of formaldehyde.
Abstract: Sugar mixtures comprising glucose and either mannose, or both, are catalytically hydrogenated in aqueous solution containing 0.2-1.5% by weight (based on sugar) of sodium carbonate or other basic reacting alkali metal salt, yielding mannitol-rich solutions of sorbitol and mannitol. Hydrogenation is preferably carried out in two stages, the first at temperature of about 60.degree.-100.degree. C., the second at temperatures of about 110.degree.-160.degree. C.
Type:
Grant
Filed:
July 13, 1979
Date of Patent:
September 29, 1981
Assignee:
ICI Americas Inc.
Inventors:
Albert J. deBerardinis, Walter M. Kruse
Abstract: A modified nickel catalyst used for stereo-differentiating reduction of carbonyl compounds is provided. The modified nickel catalyst is prepared by soaking a nickel catalyst in an aqueous modifying medium having dissolved therein at least one inorganic salt, such as sodium bromide or sodium chloride, and at least one optically active substance, such as optically active hydroxy acid. The modified nickel catalyst exhibits enhanced activity for stereo-differentiating reduction and causes little or no side reactions, and thus, brings about an extremely high yield of the reaction product.
Abstract: The instant invention is directed to a process for the production of low molecular weight polyhydric alcohols by hydrogenating formose solutions in the presence of metal catalysts comprising(a) introducing an at least 20% solution of formose, of which the pH-value was adjusted before hydrogenation to a value of from 7.5 to 12.5, in batches into a first reactor in a manner such that the content of reducible groups, determined as carbonyl groups, in the reactor does not exceed a level of 2% by weight;(b) hydrogenating the solution in batches in the presence of a total quantity of a first catalyst of from 10.sup.-4 to 5.10.sup.
Type:
Grant
Filed:
July 6, 1979
Date of Patent:
March 24, 1981
Assignee:
Bayer Aktiengesellschaft
Inventors:
Edgar Mohring, Hanns P. Muller, Kuno Wagner
Abstract: This invention relates to an improved process for the preparation of formose by the condensation of aqueous formaldehyde. In the process according to this invention, tertiary amines which contain an electrophilic hetero atom in the .beta.-position to the tertiary nitrogen atom are used for controlling the pH instead of the inorganic bases which have previously been used for this purpose.
Type:
Grant
Filed:
May 14, 1979
Date of Patent:
March 10, 1981
Assignee:
Bayer Aktiengesellschaft
Inventors:
Edgar Mohring, Hanns P. Muller, Kuno Wagner
Abstract: A process is disclosed for preparing mixtures of low molecular weight polyhydroxyl compounds and hydroxyaldehydes and hydroxyketones by condensing formaldehyde hydrate with itself in the presence of (I) as catalyst a soluble or insoluble compound of a metal of the first to eighth sub-group or second to fourth main group of the Periodic System of Elements, optionally bound to a high molecular weight carrier, and (II) more than 10% by weight, based on formaldehyde, of one or more dihydric or higher hydric low molecular weight alcohols and/or higher molecular weight polyhydroxyl compounds. The pH of the reaction mixture is held at 5.5 to 9.0 until 5-40% conversion has occurred and is then lowered to between 4.5 and 8.0 (0.5-2.0 pH units lower). The reaction is then stopped by inactivating the catalyst.
Abstract: A process for extracting xylitol from the end syrups of the xylitol crystallization by subjecting the end syrup to chromatographic separation, whereby it will be decomposed into two or more fractions, the first fraction containing mainly the polysaccharides and polysaccharide alcohols and the subsequent fractions containing essentially the pentitols and hexitols.
Abstract: A process for producing polyalcohols such as xylite from deciduous wood wherein the wood is hydrolyzed with dilute mineral acid to produce a sugar solution which is deionized and decolorized in an ion exchanger and hydrogenated to produce a polyalcohol solution which is also decolorized and deionized by ion exchange and from which pure polyalcohol is thereafter separated by crystallization, further comprising dispensing with neutralization of the acid in the sugar solution after hydrolysis, deionizing and decolorizing both the sugar solution and the polyalcohol solution in the same ion exchanger, eluting acetic acid taken up by the ion exchanger from the polyalcohol solution and displacing polyalcohol solution from the exchanger with the acid containing sugar solution, washing the ion exchanger with water only after ion exchange of the sugar solution, removing the bulk of the acetic acid from the sugar solution by evaporating the sugar solution to a higher concentration than the concentration customarily util
Type:
Grant
Filed:
June 13, 1979
Date of Patent:
December 16, 1980
Assignee:
Benckiser-Knapsack GmbH
Inventors:
Theodor Riehm, Theodor Auel, Wilhelm Spatz
Abstract: This invention relates to an improved process for the preparation of a mixture of various low molecular weight hydroxyaldehydes, hydroxyketones and polyhydric alcohols by the condensation of formaldehyde with itself. The essential feature of the improvement is that unpurified synthesis gases of the kind obtained from the large scale industrial production of formaldehyde can be used directly as the source of formaldehyde.
Abstract: A reaction in a catalyst suspension system is carried out by using a reactor equipped with a filter for separating the catalyst in the reactor.
Abstract: A process for the production of xylan and fibrinous material from vegetable raw material by treating the raw material with saturated steam at a temperature of from 160.degree. to 230.degree. C. for a period from 2 minutes to 4 hours.
Type:
Grant
Filed:
July 18, 1977
Date of Patent:
January 1, 1980
Assignee:
Projektierung Chemische Verfahrenstechnik Gesellschaft mit beschrankter Haftung
Inventors:
Hans-Hermann Dietrichs, Michael Sinner, Fritz Opderbeck, Karl-Heinz Brachthauser
Abstract: Low molecular weight polyhydroxyl compounds are made from formaldehyde hydrate by an improved process comprising adjusting the pH of an aqueous solution of formaldehyde and co-catalyst to 9-12 with calcium hydroxide at 80.degree.-110.degree. C. to begin condensation and then adding to this reaction mixture aqueous formalin and/or paraformaldehyde and calcium hydroxide to maintain a pH of 7.5-9.5 and temperature of 80.degree.-110.degree. C.
Abstract: The invention relates to a process for the conversion of lactose into useful monocarbohydrates, comprising the steps of oxidatively hydrolyzing a lactose solution to form galactose and gluconic acid, and separating these two constituents.
Abstract: An improvement in a process for the production of xylose or xylitol wherein a vegetable material is contacted with a basic substance and the solid residue is thereafter treated with an acid, the improvement resides in the use of stone nut shells, in employing a two-stage digestion initially with a 1.5-6 molar alkali metal hydroxide solution at 10.degree.-50.degree. C. and thereafter diluting the digestion mass to 0.75 molar or less and digesting at a temperature of at least 60.degree. C.
Type:
Grant
Filed:
October 4, 1976
Date of Patent:
August 8, 1978
Assignee:
Sud-Chemie Aktiengesellschaft
Inventors:
Hans Buckl, Bernd Brenner, Wolfgang Eisenschmid