2013 Fiscal Year Final Research Report
Immobilization of arsenic using acidophilic, iron-oxidizing archaeon
| Project/Area Number |
24760689
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Multi-year Fund |
|---|
| Research Field |
Earth system and resources enginnering
|
|---|
| Research Institution | Kyushu University |
|---|
Principal Investigator |
OKIBE Naoko 九州大学, 工学(系)研究科(研究院), 准教授 (30604821)
|
|---|
| Project Period (FY) |
2012-04-01 – 2014-03-31
|
| Keywords | ヒ素 / スコロダイト / バイオミネラリゼーション / 環境修復 / 製錬廃液 |
|---|
| Research Abstract |
Scorodite (FeAsO4•2H2O) is a thermodynamically stable mineral with advantages as an arsenic disposal compound. With an aim to immobilize highly toxic As(III) contained in the copper refinery process solution, eventually in the form of crystalline scorodite, the use of thermo-acidophilic iron-oxidizing archaeon, Acidianus brierleyi, was investigated. Microbial growth on yeast extract was implied to facilitate As(III) oxidation by Fe(III) on cell surface. When the initial Fe(II)/As(III) ratio was set at 1.4 in the presence of yeast extract, both ions were readily oxidized and 86-100% of As was precipitated as crystalline scorodite. The molar ratio of microbially-oxidized Fe(II) and As(III) was an important factor to determine the type of the secondary mineral formed. This study demonstrates the applicability of an one-step bioprocess which enables treatment of As(III)-bearing copper refinery process solution by producing biogenic crystalline scorodite.
|
