A radioactive sodium destruction facility includes a tank for storing liquid metallic sodium, located at a first level; a reaction vessel containing an aqueous solution; a sodium feed circuit comprising a sodium circulation member located at a second level higher than the first level, the circulation member having a suction in fluid communication with the tank and a discharge in fluid communication with the reaction vessel; an inert gas supply unit configured to supply the tank; a controller driving the sodium circulation member; and an inert gas supply unit configured to supply the tank; and a controller driving the supply unit to control a gas pressure in the tank, such that a pressure at the suction of the sodium circulation member is maintained within a predetermined range.

The present invention provides a method of preparing oxalic acid (H.sub.2C.sub.2O.sub.4), the method at least comprising the steps of: (a) providing a metal formate (HCO.sub.2M) containing stream, wherein the metal (M) of the metal formate (HCO.sub.2M) is a monovalent metal selected from the group consisting of Li, Na, K, Cs, Rb and a mixture thereof; (b) heating the metal formate (HCO.sub.2M) containing stream thereby obtaining a metal oxalate (M.sub.2C.sub.2O.sub.4) containing stream; (c) subjecting the metal oxalate (M.sub.2C.sub.2O.sub.4) containing stream to electrodialysis, thereby obtaining at least oxalic acid (M.sub.2C.sub.2O.sub.4) and a metal hydroxide (MOH).

The present invention provides a method for recycling 3-carbamoymethyl-5-methylhexanoic acid from 3-carbamoymethyl-5-methylhexanoic acid chiral resolving mother liquor. The method comprises the following steps: (a) distilling 3-carbamoymethyl-5-methylhexanoic acid chiral resolving mother liquor, adding aromatic hydrocarbon, heating to dissolve, keeping the temperature and stirring; (b) after completing the reaction in step (a), cooling the reaction solution to 30-60° C., then adding alkali liquor dropwise, keeping the temperature and reacting; and (c) after completing the reaction in step (b), cooling the reactant to 20-30° C., layering, adjusting the pH of the separated water layer to 1 to 2, performing extraction by using an organic solvent, distilling an organic phase under a reduced pressure, and crystallizing at 0±5° C. to obtain 3-carbamoymethyl-5-methylhexanoic acid. The method provided in the present invention is convenient to operate, and the recycled product is high in purity (≧99.8%) and yield.

The present invention relates to a preparation method of 4-(4-amino-3-fluorophenoxy)-N-methylpyridine-2-formamide capable of enabling 4-chlorine-N-methylpyridine-2-formamide to react with 4-amino-3-fluorophenol in the presence of an inorganic base. The present invention employs the inorganic base to replace potassium t-butoxide in the prior art, thus effectively solving the problem of a potential safety hazard of the potassium t-butoxide in industrial production. In addition, after the reaction is completed, the present invention employs a crystallization method for separation to obtain a reaction product; thus compared with the methods of extraction, concentration and column isolation and purification employed in the prior art, the present invention has a simpler operation and a lower cost, results in less environment pollution and a higher yield, and is very suitable for industrial production.

The present invention relates to a preparation method of 4-(4-amino-3-fluorophenoxy)-N-methylpyridine-2-formamide capable of enabling 4-chlorine-N-methylpyridine-2-formamide to react with 4-amino-3-fluorophenol in the presence of an inorganic base. The present invention employs the inorganic base to replace potassium t-butoxide in the prior art, thus effectively solving the problem of a potential safety hazard of the potassium t-butoxide in industrial production. In addition, after the reaction is completed, the present invention employs a crystallization method for separation to obtain a reaction product; thus compared with the methods of extraction, concentration and column isolation and purification employed in the prior art, the present invention has a simpler operation and a lower cost, results in less environment pollution and a higher yield, and is very suitable for industrial production.

A method of reducing color in an alkanolamine, the method comprising: contacting the alkanolamine with an amount of an aqueous solution effective to provide 5 to 1000 parts per million by weight of an alkali metal borohydride, based on parts by weight of the alkanolamine; and 0.5 to 10,000 parts per million by weight of an alkali metal hydroxide, based on parts by weight of the alkanolamine; preferably wherein the color-reduced alkanolamine is not distilled after the contacting.

A method of reducing color in an alkanolamine, the method comprising: contacting the alkanolamine with an amount of an aqueous solution effective to provide 5 to 1000 parts per million by weight of an alkali metal borohydride, based on parts by weight of the alkanolamine; and 0.5 to 10,000 parts per million by weight of an alkali metal hydroxide, based on parts by weight of the alkanolamine; preferably wherein the color-reduced alkanolamine is not distilled after the contacting.

A method for removing alkali metal from a hydrocarbon feedstock comprising alkali metal, non-alkali metal and sulfur. The method includes separating out at least a portion of any alkali metal sulfide and a portion of any non-alkali metal from the hydrocarbon feedstock. Hydrogen sulfide can be added to the remaining hydrocarbon feedstock to form alkali hydrosulfide from any alkali metal remaining in the hydrocarbon feedstock. The alkali hydrosulfide is then separated from the hydrocarbon feedstock. Alkali metal may be removed from the alkali metal sulfide separated out from the hydrocarbon feedstock. Alkali hydrosulfide may be treated to form alkali metal sulfide, and alkali metal may also be removed from the formed alkali metal sulfide.

A method for removing alkali metal from a hydrocarbon feedstock comprising alkali metal, non-alkali metal and sulfur. The method includes separating out at least a portion of any alkali metal sulfide and a portion of any non-alkali metal from the hydrocarbon feedstock. Hydrogen sulfide can be added to the remaining hydrocarbon feedstock to form alkali hydrosulfide from any alkali metal remaining in the hydrocarbon feedstock. The alkali hydrosulfide is then separated from the hydrocarbon feedstock. Alkali metal may be removed from the alkali metal sulfide separated out from the hydrocarbon feedstock. Alkali hydrosulfide may be treated to form alkali metal sulfide, and alkali metal may also be removed from the formed alkali metal sulfide.

A method of reducing color in an alkanolamine, the method comprising: contacting the alkanolamine with an amount of an aqueous solution effective to provide 5 to 1000 parts per million by weight of an alkali metal borohydride, based on parts by weight of the alkanolamine; and 0.5 to 10,000 parts per million by weight of an alkali metal hydroxide, based on parts by weight of the alkanolamine; preferably wherein the color-reduced alkanolamine is not distilled after the contacting.