In situ time-resolved X-ray diffraction of iron sulfides during hydrothermal pyrite growth

被引:36
作者
Cahill, CL
Benning, LG
Barnes, HL
Parise, JB
机构
[1] SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA
[2] Penn State Univ, Dept Geosci, University Pk, PA 16802 USA
[3] SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA
关键词
in situ; X-ray; pyrite; hydrothermal; mackinawite;
D O I
10.1016/S0009-2541(99)00199-0
中图分类号
P3 [地球物理学]; P59 [地球化学];
学科分类号
0708 ; 070902 ;
摘要
Pyrite formation under hydrothermal conditions has been studied using in situ time-resolved X-ray diffraction (XRD). This study employed two different synchrotron X-ray sources (National Synchrotron Light Source (NSLS), Advanced Photon Source (APS); Brookhaven and Argonne National Laboratories, USA, respectively) and two types of reaction cells (capillary and hydrothermal autoclave type) to examine reactions in the Fe-S system under both anoxic and controlled oxic conditions. Starting materials were mackinawite slurries equilibrated in reduced, H2S(aq) solutions and heated to a maximum of 190 degrees C. The results show that under fully anoxic conditions, mackinawite persists to at least 120 degrees C, while aerated (oxic) slurries transform rapidly to greigite, pyrite, magnetite and goethite. Possible reaction mechanisms are discussed in light of these results. These experiments are the first application of previously described in situ reaction cells to anoxic and oxic reactions in the Fe-S system. Finally, the capabilities of each cell type and their applicability to other systems are discussed. (C) 2000 Elsevier Science B.V. All rights reserved.
引用
收藏
页码:53 / 63
页数:11
相关论文
共 43 条
[1]  
[Anonymous], [No title captured]
[2]  
BENNING LG, UNPUB
[3]  
BENNING LG, 1999, P 9 V M GOLDSCHM C L, V971, P24
[5]   THERMODYNAMIC STABILITY OF SEDIMENTARY IRON SULFIDES [J].
BERNER, RA .
AMERICAN JOURNAL OF SCIENCE, 1967, 265 (09) :773-&
[6]   SEDIMENTARY PYRITE FORMATION [J].
BERNER, RA .
AMERICAN JOURNAL OF SCIENCE, 1970, 268 (01) :1-&
[7]   Structure of microporous QUI-MnGS-1 and in situ studies of its formation using time-resolved synchrotron x-ray powder diffraction [J].
Cahill, CL ;
Ko, YH ;
Hanson, JC ;
Tan, KM ;
Parise, JB .
CHEMISTRY OF MATERIALS, 1998, 10 (05) :1453-1458
[8]   In situ studies of the sol-gel synthesis of materials [J].
Cheetham, AK ;
Mellot, CF .
CHEMISTRY OF MATERIALS, 1997, 9 (11) :2269-2279
[9]   In situ synchrotron x-ray powder diffraction studies of crystallization of microporous aluminophosphates and Me2+-substituted aluminophosphates [J].
Christensen, AN ;
Jensen, TR ;
Norby, P ;
Hanson, JC .
CHEMISTRY OF MATERIALS, 1998, 10 (06) :1688-1693
[10]  
Cruciani G, 1997, AM MINERAL, V82, P729