Synthesis of water-soluble compounds of platinum group metals in molten glass media

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K05199
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 34030:Green sustainable chemistry and environmental chemistry-related
• Research Institution: University of Fukui
• Principal Investigator: Okada Takashi 福井大学, 学術研究院工学系部門, 准教授 (30641625)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 白金族金属 / 水溶化 / 酸化 / 錯形成 / リサイクル / 溶融媒体

Outline of Final Research Achievements

Synthesis of water-soluble PGM compounds in a molten alkaline borate media was studied for the purpose of extracting PGMs without hazardous aqua regia in PGM recycling processes. Chemical forms of the compounds were investigated by spectroscopic methods, and effects of components of the molten media (cations and anions) and heating duration on the PGM solubilization efficiencies were evaluated. In the molten media, water-soluble and dilute acid-soluble PGM compounds were generated, and PGMs, Al, B, and alkaline metals were present in latter compounds. The solubilities of the compounds depended on the proportion of the elements and their chemical states. Pt and Pd tended to form water-soluble compounds, whereas Rh did dilute acid-soluble compounds. Among Li, Na, K, and Cs, molten media in potassium system produced large quantities of the water-soluble PGM compounds.

Free Research Field

化学

Academic Significance and Societal Importance of the Research Achievements

従来のPGMリサイクルでは、強力な酸化剤を有する酸（王水、塩素ガスと塩酸）を用いてPGMsを溶解する。これらの酸は腐食性が高く有害であり、環境負荷低減の観点から使用を避けることが望ましい。本手法をPGMリサイクルに応用することができれば、クリーンな水によるPGM溶解プロセスを開発することにつながるため、社会的に意義がある。また、PGMsと他成分の複合酸化物を対象とし、水溶性の形態に変換することに着目した点に特色がある。アルカリホウ酸塩媒体における水溶性PGM複合酸化物の生成挙動に関するデータは、水溶化反応の制御方法を確立するうえで有用であり、学術的に意義がある。