大学院工学研究院

吉村 彰大

ヨシムラ アキヒロ  (Akihiro Yoshimura)

基本情報

所属
千葉大学 大学院工学研究院 融合理工学府 助教

J-GLOBAL ID
201901013636777170
researchmap会員ID
B000349357

受賞

 1

主要な論文

 15
  • Akihiro Yoshimura, Koyo Suemasu, Marcello M. Veiga
    Journal of Sustainable Metallurgy 2021年7月7日  査読有り
    <sec> <title>Abstract</title> Artisanal and small-scale gold mining (ASGM) utilizes mercury (Hg) for the extraction of gold (Au) and is responsible for the largest anthropogenic source of emissions and releases of Hg to the environment. Previous estimates of Hg use in ASGM have varied widely. In this effort, Hg losses in ASGM were derived from the difference between estimates of total Au production and the production reported by conventional gold mining. On the basis of this result, the average ratio of Hg lost to Au produced in ASGM was estimated to be 1.96 in Africa, 4.63 in Latin America, and 1.23 in Asia. The difference among regions can be attributed to the amalgamation procedure used by the miners, in which whole-ore amalgamation is predominant in Latin America and Asia. The obtained estimated ratio of Hglost:Auproduced suggested the possibility to detect either Au or Hg smuggling from one country to another. On the other hand, the importance of considering cyanidation in ASGM was also suggested. </sec><sec> <title>Graphical Abstract</title> </sec>
  • Akihiro Yoshimura, Shunta Tochigi, Yasunari Matsuno
    JOURNAL OF SUSTAINABLE METALLURGY 7(1) 266-276 2021年3月  
    In this research, a recycling process for palladium using "dry aqua regia," which consists of iron(III) chloride-potassium chloride, was proposed. Palladium was dissolved in "dry aqua regia," and the dissolved palladium was recovered by leaching with potassium chloride solution with added ammonium chloride and nitric acid. Palladium was almost completely dissolved in 3 h at 600 K, and the recovery ratio of dissolved palladium was up to 80%. In addition, the dissolution of palladium in coexistence with platinum and the dissolution of platinum-palladium alloy by "dry aqua regia" were also tested. The dissolved palladium and platinum were separated and recovered by solid-liquid separation technique using the difference in solubility of their compounds in potassium chloride and sodium chloride solutions. As a result, pure compounds of each element were recovered. This result suggested the possibility of using "dry aqua regia" for the separation of platinum-group metals.Graphical Abstract

MISC

 19

共同研究・競争的資金等の研究課題

 5