The present invention relates to a method of carrying out an organic reaction in aqueous solution in the presence of a hydroxyalkyl(alkyl)cellulose or an alkylcellulose.

A method is disclosed for stripping in a stripper a urea synthesis solution received from a urea forming process wherein ammonia and CO2 are reacted under urea forming conditions. The shell space of the stripper comprises a continuous vertical zone.

This invention provides for synthesis of citrulline from a transition metal complex of ornithine using cyanate to derivatize the terminal amino group of ornithine. The invention also provides improved methods for purification of citrulline produced by reaction of cyanate with ornithine via the steps of reprecipitation of copper complex of citrulline, removal of the complexing metal by sulfide precipitation, activated carbon adsorption and antisolvent crystallization.

This invention provides for synthesis of citrulline from a transition metal complex of ornithine using cyanate to derivatize the terminal amino group of ornithine. The invention also provides improved methods for purification of citrulline produced by reaction of cyanate with ornithine via the steps of reprecipitation of copper complex of citrulline, removal of the complexing metal by sulfide precipitation, activated carbon adsorption and antisolvent crystallization.

A method is disclosed for stripping in a stripper a urea synthesis solution received from a urea forming process wherein ammonia and CO2 are reacted under urea forming conditions. The shell space of the stripper comprises a continuous vertical zone.

The present invention relates to a method of carrying out an organic reaction in aqueous solution in the presence of a hydroxyalkyl(alkyl)cellulose or an alkylcellulose.

A process for the production of biuret from urea wherein: a urea aqueous solution (24) withdrawn from the recovery section of a urea plant is processed to remove water and obtain a concentrated urea melt (25); said urea melt is processed under biuret-forming conditions to decompose urea into biuret and ammonia and obtain a high-biuret urea melt (26); said high-biuret urea melt (26) is diluted with water or with an aqueous stream obtaining a solution (28); the solution (28) is subject to crystallization and precipitation of a solid phase containing biuret which is separated from the aqueous phase.

A process for the production of biuret from urea wherein: a urea aqueous solution (24) withdrawn from the recovery section of a urea plant is processed to remove water and obtain a concentrated urea melt (25); said urea melt is processed under biuret-forming conditions to decompose urea into biuret and ammonia and obtain a high-biuret urea melt (26); said high-biuret urea melt (26) is diluted with water or with an aqueous stream obtaining a solution (28); the solution (28) is subject to crystallization and precipitation of a solid phase containing biuret which is separated from the aqueous phase.

A method for preparing a latent hardener includes, in the order recited, introducing a hardener into a dry mixer that is a high-energy-type mixer; injecting carbon dioxide gas or an inert gas into the dry mixer; and mechanochemically deactivating only a surface of the hardener using the dry mixer. The hardener may be an amine-based adduct, an imidazole-based adduct, dicyandiamide, a dihydride-based compound, a dichlorophenyl dimethylurea compound and combinations thereof. The inert gas may be helium, nitrogen, argon, neon, krypton, and combinations thereof.

A method for preparing a latent hardener includes, in the order recited, introducing a hardener into a dry mixer that is a high-energy-type mixer; injecting carbon dioxide gas or an inert gas into the dry mixer; and mechanochemically deactivating only a surface of the hardener using the dry mixer. The hardener may be an amine-based adduct, an imidazole-based adduct, dicyandiamide, a dihydride-based compound, a dichlorophenyl dimethylurea compound and combinations thereof. The inert gas may be helium, nitrogen, argon, neon, krypton, and combinations thereof.