The invention relates to a method for regenerating the extractive potential of an organic hydroxyoxime-based extraction solution used in the recovery of metals by liquid-liquid extraction. The method is two-stage, in which a solid hydroxylamine is used in the reaction stage, and the removal of the undesirable compounds generated in the reaction occurs in the second stage by adsorption purification. The method of the invention is suitable for treatment of degraded oxime metal extractants in various process organic solutions both in aldehyde and ketoxime extractant solutions. The method can also be used to treat a mixture of degraded oxime extractants.

A method for synthesizing a ketoxime is provided. In a system of an aqueous carbonate solution, a reaction is performed on a ketone, ammonia and hydrogen peroxide by using a titanium-silicon molecular sieve as a catalyst to obtain the ketoxime. Moreover, a reaction progress is judged and an optimal reaction ratio is determined by a real-time monitoring of a pH value in a reaction system during the reaction. In the present invention, by monitoring the pH value in the reaction system, the progress of the reaction is judged, thereby determining the optimal reaction ratio. The pH of the system is further adjusted by an aqueous carbonate solution to increase the reaction velocity and conversion rate of the ammonia.

A method for synthesizing a ketoxime is provided. In a system of an aqueous carbonate solution, a reaction is performed on a ketone, ammonia and hydrogen peroxide by using a titanium-silicon molecular sieve as a catalyst to obtain the ketoxime. Moreover, a reaction progress is judged and an optimal reaction ratio is determined by a real-time monitoring of a pH value in a reaction system during the reaction. In the present invention, by monitoring the pH value in the reaction system, the progress of the reaction is judged, thereby determining the optimal reaction ratio. The pH of the system is further adjusted by an aqueous carbonate solution to increase the reaction velocity and conversion rate of the ammonia.

A method for synthesizing a ketoxime is provided. In a system of an aqueous carbonate solution, a reaction is performed on a ketone, ammonia and hydrogen peroxide by using a titanium-silicon molecular sieve as a catalyst to obtain the ketoxime. Moreover, a reaction progress is judged and an optimal reaction ratio is determined by a real-time monitoring of a pH value in a reaction system during the reaction. In the present invention, by monitoring the pH value in the reaction system, the progress of the reaction is judged, thereby determining the optimal reaction ratio. The pH of the system is further adjusted by an aqueous carbonate solution to increase the reaction velocity and conversion rate of the ammonia.

A method for synthesizing a ketoxime is provided. In a system of an aqueous carbonate solution, a reaction is performed on a ketone, ammonia and hydrogen peroxide by using a titanium-silicon molecular sieve as a catalyst to obtain the ketoxime. Moreover, a reaction progress is judged and an optimal reaction ratio is determined by a real-time monitoring of a pH value in a reaction system during the reaction. In the present invention, by monitoring the pH value in the reaction system, the progress of the reaction is judged, thereby determining the optimal reaction ratio. The pH of the system is further adjusted by an aqueous carbonate solution to increase the reaction velocity and conversion rate of the ammonia.

Provided are: a method for producing a mycrosporine-like amino acid (MAA) that includes a step in which microbes are cultivated that produce MAA on the outside of bacterial cells, a step in which the bacterial cells and extracellular culture fluid are separated, and a step in which the MAA is recovered from the extracellular culture fluid; an MAA indicated by formula (1), an MAA produced using this method, or an ultraviolet-absorbing composition including the MAA indicated by formula (1); and a composition including the MAA produced using this method or the MAA indicated by formula (1), for preventing at least one symptom or disease selected from a group comprising acute skin reactions, aging of the skin, and skin cancer. ##STR00001##

Provided are: a method for producing a mycrosporine-like amino acid (MAA) that includes a step in which microbes are cultivated that produce MAA on the outside of bacterial cells, a step in which the bacterial cells and extracellular culture fluid are separated, and a step in which the MAA is recovered from the extracellular culture fluid; an MAA indicated by formula (1), an MAA produced using this method, or an ultraviolet-absorbing composition including the MAA indicated by formula (1); and a composition including the MAA produced using this method or the MAA indicated by formula (1), for preventing at least one symptom or disease selected from a group comprising acute skin reactions, aging of the skin, and skin cancer. ##STR00001##

The present invention provides an improved process for the preparation of exametazime, which is used as ligand in preparation of technetium-99m complex. ##STR00001##

The present invention provides an improved process for the preparation of exametazime, which is used as ligand in preparation of technetium-99m complex. ##STR00001##

The present invention provides an improved process for the preparation of exametazime, which is used as ligand in preparation of technetium-99m complex. ##STR00001##