H₂S_(g) removal using a modified, low-pH liquid redox sulfur recovery (LRSR) process with electrochemical regeneration of the Fe catalyst couple

TY - JOUR

T1 - H2S(g) removal using a modified, low-pH liquid redox sulfur recovery (LRSR) process with electrochemical regeneration of the Fe catalyst couple

AU - Gendel, Youri

AU - Levi, No'omi

AU - Lahav, Ori

PY - 2009/11/1

Y1 - 2009/11/1

N2 - A modified pH 1.0 liquid redox sulfur recovery (LRSR) process, based on reactive absorption of H2S(g) in an acidic (pH 1.0) iron solution ([Fe(III)] = 9-8 g L-1, [Fe(II)] = 1-2 g L-1) and electrochemical regeneration of the Fe(III)/Fe(II) catalyst couple, is introduced. Fe(II) was oxidized in a flow-through electrolytic cell by Cl 2(aq) formed on a Ti/RuO2 anode. pH 1.0 was applied to retard the potential precipitation of predominantly jarosite group Fe(III) species. At pH 1.0, the presence of chloride ions at [Cl-] = 30 g L-1 allows for both efficient (indirect) electrochemical oxidation of Fe(II) and efficient H2S(g) reactive absorption. The latter observation was hypothesized to be associated with higher concentrations of Fe(III)-Cl complexes that are more highly reactive toward H2S (aq) than are free Fe(III) ions and Fe-SO4 complexes that otherwise dominate pH 1.0 Fe(III) solutions in the absence of a significant Cl-concentration. At the described operational conditions the rate of Fe(II) oxidation in the experimental system was 0.793 kg Fe h-1 per m2 anode surface area, at a current efficiency of 58%. Electricity cost within the electrochemical step was approximated at $0.9 per kg H2S(g) removed.

AB - A modified pH 1.0 liquid redox sulfur recovery (LRSR) process, based on reactive absorption of H2S(g) in an acidic (pH 1.0) iron solution ([Fe(III)] = 9-8 g L-1, [Fe(II)] = 1-2 g L-1) and electrochemical regeneration of the Fe(III)/Fe(II) catalyst couple, is introduced. Fe(II) was oxidized in a flow-through electrolytic cell by Cl 2(aq) formed on a Ti/RuO2 anode. pH 1.0 was applied to retard the potential precipitation of predominantly jarosite group Fe(III) species. At pH 1.0, the presence of chloride ions at [Cl-] = 30 g L-1 allows for both efficient (indirect) electrochemical oxidation of Fe(II) and efficient H2S(g) reactive absorption. The latter observation was hypothesized to be associated with higher concentrations of Fe(III)-Cl complexes that are more highly reactive toward H2S (aq) than are free Fe(III) ions and Fe-SO4 complexes that otherwise dominate pH 1.0 Fe(III) solutions in the absence of a significant Cl-concentration. At the described operational conditions the rate of Fe(II) oxidation in the experimental system was 0.793 kg Fe h-1 per m2 anode surface area, at a current efficiency of 58%. Electricity cost within the electrochemical step was approximated at $0.9 per kg H2S(g) removed.

UR - http://www.scopus.com/inward/record.url?scp=70350747585&partnerID=8YFLogxK

U2 - 10.1021/es901594j

DO - 10.1021/es901594j

M3 - 文章

C2 - 19924962

AN - SCOPUS:70350747585

VL - 43

SP - 8315

EP - 8319

JO - Environmental Science & Technology

JF - Environmental Science & Technology

SN - 0013-936X

IS - 21

ER -