Abstract: A method allowing production of high-purity perrhenic acid from rhenium sulfide by applying pyrometallurgical process is provided.

Abstract: A method for allowing production of high-purity perrhenic acid from crude rhenium sulfide by applying a dry process is provided. A method for producing an aqueous solution of perrhenic acid includes 1) a step for roasting rhenium sulfide under an oxygen-containing gas to collect gasified rhenium oxide; 2) a step for cooling and solidifying the gasified rhenium oxide while keeping sulfur oxide entrained in the gasified rhenium oxide a gaseous state, and subsequently performing solid-gas separation, thereby improving purity of rhenium oxide; and 3) a step for dissolving the solidified rhenium oxide into water, or heating and gasifying the solidified rhenium oxide and then dissolving the gasified rhenium oxide into water, to obtain the aqueous solution of perrhenic acid.

Abstract: A method for allowing production of high-purity perrhenic acid from crude rhenium sulfide by applying a dry process is provided. A method for producing an aqueous solution of perrhenic acid includes 1) a step for roasting rhenium sulfide under an oxygen-containing gas to collect gasified rhenium oxide; 2) a step for cooling and solidifying the gasified rhenium oxide while keeping sulfur oxide entrained in the gasified rhenium oxide a gaseous state, and subsequently performing solid-gas separation, thereby improving purity of rhenium oxide; and 3) a step for dissolving the solidified rhenium oxide into water, or heating and gasifying the solidified rhenium oxide and then dissolving the gasified rhenium oxide into water, to obtain the aqueous solution of perrhenic acid.

Abstract: A method allowing production of high-purity perrhenic acid from rhenium sulfide by applying pyrometallurgical process is provided.

Abstract: The purpose of the present invention is to provide a method to more easily analyze the concentration of glue in an electrolyte solution, while suppressing the degradation of glue during the analysis. There is provided a method for analyzing the concentration of glue contained in an electrolyte solution containing the electrolyte components by using high performance liquid chromatography, where said method comprises a step wherein an electrolyte solution is added into the eluent pH of which has been adjusted equal to or less than 5 by adding acid to an aqueous solution of phosphate of alkaline metal or alkaline earth metal, a step wherein the eluent into which the electrolyte solution has been added is passed through a separation column the exclusion limit molecular weight of which is 4000-6000 for separating the glue and electrolyte components, and a step wherein the separated glue is detected by a detector.

Abstract: The purpose of the present invention is to provide a method which makes it possible to analyze more easily the concentration of glue in an electrolyte solution, while surpressing the degradation of glue during the analysis. There is provided a method for analyzing the concentration of glue contained in an electrolyte solution containing the electrolyte components by using high performance liquid chromatography, characterized in that said method comprises a step wherein an electrolyte solution is added into the eluent pH of which has been adjusted equal to or less than 5 by adding acid to an aqueous solution of phosphate of alkaline metal or alkaline earth metal, a step wherein the eluent into which the electrolyte solution has been added is passed through a separation column the exclusion limit molecular weight of which is 4000-6000 for separating the glue and electrolyte components, and a step wherein the separated glue is detected by a detector.