Thermodynamics and Kinetics of Sulfide Oxidation by Oxygen: A Look at Inorganically Controlled Reactions and Biologically Mediated Processes in the Environment

نویسندگان

  • George W. Luther
  • Alyssa J. Findlay
  • Daniel J. MacDonald
  • Shannon M. Owings
  • Thomas E. Hanson
  • Roxanne A. Beinart
  • Peter R. Girguis
چکیده

The thermodynamics for the first electron transfer step for sulfide and oxygen indicates that the reaction is unfavorable as unstable superoxide and bisulfide radical ions would need to be produced. However, a two-electron transfer is favorable as stable S(0) and peroxide would be formed, but the partially filled orbitals in oxygen that accept electrons prevent rapid kinetics. Abiotic sulfide oxidation kinetics improve when reduced iron and/or manganese are oxidized by oxygen to form oxidized metals which in turn oxidize sulfide. Biological sulfur oxidation relies on enzymes that have evolved to overcome these kinetic constraints to affect rapid sulfide oxidation. Here we review the available thermodynamic and kinetic data for H(2)S and HS• as well as O(2), reactive oxygen species, nitrate, nitrite, and NO(x) species. We also present new kinetic data for abiotic sulfide oxidation with oxygen in trace metal clean solutions that constrain abiotic rates of sulfide oxidation in metal free solution and agree with the kinetic and thermodynamic calculations. Moreover, we present experimental data that give insight on rates of chemolithotrophic and photolithotrophic sulfide oxidation in the environment. We demonstrate that both anaerobic photolithotrophic and aerobic chemolithotrophic sulfide oxidation rates are three or more orders of magnitude higher than abiotic rates suggesting that in most environments biotic sulfide oxidation rates will far exceed abiotic rates due to the thermodynamic and kinetic constraints discussed in the first section of the paper. Such data reshape our thinking about the biotic and abiotic contributions to sulfide oxidation in the environment.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Comparison of thermodynamics and kinetics of reaction of the ozone with mercury, silver and gold

In this work, we report results of calculations based on the density functional theory of different species metal-ozone, containing mercury, silver and gold. The chosen species range from small molecules and large transition-metal containing ozone with mercury, silver and gold complexes. A comparative analysis of the description of the metal-oxygen bond obtained by different methodologies is pr...

متن کامل

Thermodynamics and Kinetics of Vaporization of Pbs From Complex Cu-Fe Mattes

Thermodynamics and kinetics of vaporization of lead sulfide from typical copper-smelting mattes of commercial interest are investigated in the temperature range 1388 K to 1573 K by vapor transport technique and plasma arc spectroscopy. The total mass of the dominant vaporizing species PbS that leaves the matte is described by the Newman's numerical solution to the second Fick's law combined wit...

متن کامل

Hydrolysis of semi mustard (S.M) by MnCo2O4 (MnO-Co2O3) nanocomposite as a binary oxide catalyst: kinetics reactions study

MnCo2O4 (MnO-Co2O3) nanocomposite as a binary oxide has been successfully prepared by precipitation method using cobalt nitrate and manganese nitrate as the precursors and then characterized by scanning electron microscopy-energy dispersive micro-analysis (SEM-EDX) and X-ray diffraction (XRD) techniques. In this work, we report the hydrolysis kinetics reactions of semi mustard (chloroethyl ethy...

متن کامل

Hydrolysis of semi mustard (S.M) by MnCo2O4 (MnO-Co2O3) nanocomposite as a binary oxide catalyst: kinetics reactions study

MnCo2O4 (MnO-Co2O3) nanocomposite as a binary oxide has been successfully prepared by precipitation method using cobalt nitrate and manganese nitrate as the precursors and then characterized by scanning electron microscopy-energy dispersive micro-analysis (SEM-EDX) and X-ray diffraction (XRD) techniques. In this work, we report the hydrolysis kinetics reactions of semi mustard (chloroethyl ethy...

متن کامل

Voltammetric and Potentiometric Behavior of 2-Pyridinethiol, 2-Mercaptoethanol and Sulfide at Iron(II) Phtalocyanine Modified Carbon-Paste Electrode

A carbon-past electrode modified with iron(II) phathalocyanine (FePc) was used as a sensitive potentiometric sensor for determination of 2-pyridinethiol (2PT). 2-mercaptoethanol (2ME) and sulfide ion in aqueous solutions. The modified electrode acts as an electrocatalyst for oxidation of these compounds, and lowers the overpotential for oxidation reactions by more than 400 mV, compared to t...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره 2  شماره 

صفحات  -

تاریخ انتشار 2011