Abstract:
Disclosed is a process for extending the useful life of a hydrogenation catalyst for making diamines in which 2-methylglutaronitrile and adiponitrile are charged separately to the catalyst in sequence with an intervening step of contacting the catalyst with hydrogen and ammonia at elevated temperature.
Abstract:
The invention provides an oxygen Andrussow process for production of hydrogen cyanide from a methane-containing feedstock such as natural gas in the presence of oxygen and ammonia over a platinum catalyst, wherein the production of byproduct organonitrile impurities, such as acrylonitrile, is reduced. Limiting the content of C 2 + hydrocarbons in the methane feedstock in the oxygen Andrussow process, in contrast to the air Andrussow process, has been found to reduce formation of organonitriles, such as acrylonitrile. The organonitrile impurities can require additional processing for removal, cause fouling of equipment, and can also contribute to hydrogen cyanide polymerization. Reduction of C 2 + hydrocarbon levels to less than 2 wt%, or 1 wt%, or less than 0.1 wt%, in the methane can provide an improved yield of higher purity HCN. Reduction of C 2 + hydrocarbon levels also solves the problem of polymer buildup in process equipment, reducing downtime required for cleaning when higher C 2 + hydrocarbon levels are present in the reaction feed.
Abstract:
The system and methods described herein solve problems of inaccurate flow control, loss of optimum reactant gas feed ratios, and the associated inefficiencies brought on by variable humidity in reactant feedstream gases during production of hydrogen cyanide by an Andrussow process.
Abstract:
Claimed is a process for producing a phosphorus-containing ligand, preferably a diphosphite ligand structure (DLS) such as structure I. The method includes contacting a phosphorochloridite (structure II) with a compound having the structure X-OH (which can be a bisaryl compound), and a tertiary organic amine to provide structure I' and as prefered embodiment structure I.
Abstract:
The invention provides an oxygen Andrussow process for production of hydrogen cyanide from a methane-containing feedstock such as natural gas in the presence of oxygen and ammonia over a platinum catalyst, wherein the production of byproduct organonitrile impurities, such as acrylonitrile, is reduced. Limiting the content of C 2 + hydrocarbons in the methane feedstock in the oxygen Andrussow process, in contrast to the air Andrussow process, has been found to reduce formation of organonitriles, such as acrylonitrile. The organonitrile impurities can require additional processing for removal, cause fouling of equipment, and can also contribute to hydrogen cyanide polymerization. Reduction of C 2 + hydrocarbon levels to less than 2 wt%, or 1 wt%, or less than 0.1 wt%, in the methane can provide an improved yield of higher purity HCN. Reduction of C 2 + hydrocarbon levels also solves the problem of polymer buildup in process equipment, reducing downtime required for cleaning when higher C 2 + hydrocarbon levels are present in the reaction feed.
Abstract:
An improved process for the hydrolysis of nylon polymer is herein disclosed using ionic liquids and optionally one equivalent of sulfuric acid per amide residue of the polymer. The process provides for a simplified means for separation of the hydrolyzed polyamide constituent monomers.
Abstract:
Processes and systems for the production of hydrogen cyanide via the Andrussow process are described. A reaction zone, wherein oxygen, ammonia, and methane can be allowed to react in the presence of a catalyst comprising platinum to provide hydrogen cyanide. A desulfurization zone, wherein a feed stream comprising sulfur and at least one of the oxygen, the ammonia, and the methane can be contacted with a desulfurization material to produce a sulfur- reduced feed stream that is provided to the reaction zone. In an example, the desulfurization material includes zinc oxide.