Aqueous oxidation-reduction kinetics associated with coupled electron-cation transfer from iron-containing silicates at 25°C

Details Aqueous oxidation-reduction kinetics associated with coupled electron-cation transfer from iron-containing silicates at 25°C Aqueous oxidation-reduction kinetics associated with coupled electron-cation transfer from iron-containing silicates at 25°C

May 1985

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1985gecoa..49.1263w&link_type=abstract

Geochimica et Cosmochimica Acta, vol. 49, Issue 5, pp.1263-1275

Physics

14

Scientific paper

Mechanisms and kinetics of aqueous Fe +2 / Fe +3 oxidation-reduction and dissolved O 2 interaction in the presence of augite, biotite and hornblende were studied in oxic and anoxic solutions at pH 1-9 at 25°C. Oxidation of surface iron on the minerals coincided with both surface release of Fe +2 and by reduction of Fe +3 in solution. Reaction with iron silicates consumed dissolved oxygen at a rate that increased with decreasing pH. Both Fe +3 and O 2 consumption were shown to be controlled by coupled electron-cation transfer reactions of the form; [Fe +2 , 1/ zM + z ] silicate + Fe +3 [Fe +3 ] silicate + Fe +2 + 1/ zM + z and where M is a cation of charge +z. The spontaneous reduction of aqueous Fe +3 in the presence of precipitated Fe(OH) 3 bracketed the surface oxidation standard half cell between +0.33 and +0.52 volts. Concurrent hydrolysis reactions involving cation release from the iron silicates were suppressed by the above reactions. Calculated oxidation depths in the minerals varied between 12 and 80Å and were apparently controlled by rates of solid-state cation diffusion.

Affiliated with

Also associated with

No associations

Rating

Aqueous oxidation-reduction kinetics associated with coupled electron-cation transfer from iron-containing silicates at 25°C does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Aqueous oxidation-reduction kinetics associated with coupled electron-cation transfer from iron-containing silicates at 25°C, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Aqueous oxidation-reduction kinetics associated with coupled electron-cation transfer from iron-containing silicates at 25°C will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1631919