Hematite-Catalysed Scorodite Formation as a Novel Arsenic Immobilisation Strategy Under Ambient Conditions

Scorodite is an important mineral not only for arsenic (As) removal from industrial wastewaters but also in the mobility and final fate of As in waste rocks, contaminated soils and sediments, and mine tailings. Because of the mineral's high As-loading capacity and stability, numerous studies ha...

Full description

Saved in:
Bibliographic Details
Main Authors: Tabelin, Carlito Baltazar, Corpuz, Ryan D, Igarashi, Toshifumi, Villacorte-Tabelin, Mylah, Ito, Mayumi, Hiroyoshi, Naoki
Format: text
Published: Archīum Ateneo 2019
Subjects:
Online Access:https://archium.ateneo.edu/clean-water-sanitation/1
https://www.sciencedirect.com/science/article/abs/pii/S0045653519312433#!
Tags: Add Tag
No Tags, Be the first to tag this record!
Institution: Ateneo De Manila University
id ph-ateneo-arc.clean-water-sanitation-1000
record_format eprints
spelling ph-ateneo-arc.clean-water-sanitation-10002022-03-08T04:14:21Z Hematite-Catalysed Scorodite Formation as a Novel Arsenic Immobilisation Strategy Under Ambient Conditions Tabelin, Carlito Baltazar Corpuz, Ryan D Igarashi, Toshifumi Villacorte-Tabelin, Mylah Ito, Mayumi Hiroyoshi, Naoki Scorodite is an important mineral not only for arsenic (As) removal from industrial wastewaters but also in the mobility and final fate of As in waste rocks, contaminated soils and sediments, and mine tailings. Because of the mineral's high As-loading capacity and stability, numerous studies have been done to understand its formation. Unfortunately, most of these studies were limited to elevated temperatures (>70 °C), so the processes involved in scorodite formation under ambient conditions remain unclear. This study provides evidence of the catalytic effects of hematite on the formation of scorodite at 25 °C in a pyrite-rich natural geologic material. Scorodite peaks were detected in the XRD patterns of the leaching residues with and without hematite, but those in the former were stronger and more pronounced than the latter. These results suggest that the formation of scorodite was catalysed by hematite, a generalisation that is further supported by strong characteristic IR absorption bands of scorodite at 819 cm–1 (As–O bending vibration), 785 and 725 cm–1 (As–O stretching vibrations), and 2990 cm−1 (OH-vibration) as well as the distinct XPS binding energies of Fe(III)–As (709.7 eV), As(V)–O (44.8, 44.31 and 43.7 eV), O2− (530.5 eV) and coordinated water (531.3 eV) in scorodite. This phenomenon could be attributed to three possible mechanisms: (1) more rapid precipitation promoted by the “seeding” effect of hematite particles, (2) additional supply of Fe3+ from hematite dissolution under acidic conditions, and (3) enhanced oxidations of Fe2+ to Fe3+ and As(III) to As(V) on the surface of hematite. 2019-06-03T07:00:00Z text https://archium.ateneo.edu/clean-water-sanitation/1 https://www.sciencedirect.com/science/article/abs/pii/S0045653519312433#! Goal 6: Clean Water and Sanitation Archīum Ateneo Scorodite Arsenic Wastewaters Waste rock and mine tailings Acid mine drainage Chemistry Physics Water Resource Management
institution Ateneo De Manila University
building Ateneo De Manila University Library
continent Asia
country Philippines
Philippines
content_provider Ateneo De Manila University Library
collection archium.Ateneo Institutional Repository
topic Scorodite
Arsenic
Wastewaters
Waste rock and mine tailings
Acid mine drainage
Chemistry
Physics
Water Resource Management
spellingShingle Scorodite
Arsenic
Wastewaters
Waste rock and mine tailings
Acid mine drainage
Chemistry
Physics
Water Resource Management
Tabelin, Carlito Baltazar
Corpuz, Ryan D
Igarashi, Toshifumi
Villacorte-Tabelin, Mylah
Ito, Mayumi
Hiroyoshi, Naoki
Hematite-Catalysed Scorodite Formation as a Novel Arsenic Immobilisation Strategy Under Ambient Conditions
description Scorodite is an important mineral not only for arsenic (As) removal from industrial wastewaters but also in the mobility and final fate of As in waste rocks, contaminated soils and sediments, and mine tailings. Because of the mineral's high As-loading capacity and stability, numerous studies have been done to understand its formation. Unfortunately, most of these studies were limited to elevated temperatures (>70 °C), so the processes involved in scorodite formation under ambient conditions remain unclear. This study provides evidence of the catalytic effects of hematite on the formation of scorodite at 25 °C in a pyrite-rich natural geologic material. Scorodite peaks were detected in the XRD patterns of the leaching residues with and without hematite, but those in the former were stronger and more pronounced than the latter. These results suggest that the formation of scorodite was catalysed by hematite, a generalisation that is further supported by strong characteristic IR absorption bands of scorodite at 819 cm–1 (As–O bending vibration), 785 and 725 cm–1 (As–O stretching vibrations), and 2990 cm−1 (OH-vibration) as well as the distinct XPS binding energies of Fe(III)–As (709.7 eV), As(V)–O (44.8, 44.31 and 43.7 eV), O2− (530.5 eV) and coordinated water (531.3 eV) in scorodite. This phenomenon could be attributed to three possible mechanisms: (1) more rapid precipitation promoted by the “seeding” effect of hematite particles, (2) additional supply of Fe3+ from hematite dissolution under acidic conditions, and (3) enhanced oxidations of Fe2+ to Fe3+ and As(III) to As(V) on the surface of hematite.
format text
author Tabelin, Carlito Baltazar
Corpuz, Ryan D
Igarashi, Toshifumi
Villacorte-Tabelin, Mylah
Ito, Mayumi
Hiroyoshi, Naoki
author_facet Tabelin, Carlito Baltazar
Corpuz, Ryan D
Igarashi, Toshifumi
Villacorte-Tabelin, Mylah
Ito, Mayumi
Hiroyoshi, Naoki
author_sort Tabelin, Carlito Baltazar
title Hematite-Catalysed Scorodite Formation as a Novel Arsenic Immobilisation Strategy Under Ambient Conditions
title_short Hematite-Catalysed Scorodite Formation as a Novel Arsenic Immobilisation Strategy Under Ambient Conditions
title_full Hematite-Catalysed Scorodite Formation as a Novel Arsenic Immobilisation Strategy Under Ambient Conditions
title_fullStr Hematite-Catalysed Scorodite Formation as a Novel Arsenic Immobilisation Strategy Under Ambient Conditions
title_full_unstemmed Hematite-Catalysed Scorodite Formation as a Novel Arsenic Immobilisation Strategy Under Ambient Conditions
title_sort hematite-catalysed scorodite formation as a novel arsenic immobilisation strategy under ambient conditions
publisher Archīum Ateneo
publishDate 2019
url https://archium.ateneo.edu/clean-water-sanitation/1
https://www.sciencedirect.com/science/article/abs/pii/S0045653519312433#!
_version_ 1728621273633783808