Autori: C.F. Petre and F. Larachi

Editorial: Industrial and Engineering Chemistry Research, 44, p.9391-9397, 2005.

Rezumat:

Hydrogen sulfide is the most abundant contaminant among the total reduced sulfur (TRS) quartet in the Kraft mill atmospheric emissions. An advantage of the association of oxygen with TRS in the pulp and paper effluents is exploited in a new bifunctional redox scrubbing process based on iron chemistry for the removal of hydrogen sulfide. As synthesized iron/cerium (hydr)oxide composite materials were tested at ambient and alkaline conditions in an agitated batch reactor for oxidizing dissolved bisulfide (HS-) in both aerobic and anoxic environments. Polysulfides and thiosulfate were the main detected reaction products. The presence of dissolved oxygen contributed to the sustained active surface iron sites regeneration thereby improving significantly HS- removal. Testing the material in three-cycle bisulfide oxidation without reactivation and in presence of oxygen, demonstrated its long-term efficiency.

Cuvinte cheie: Pulp and paper industry, desulfurization, bifunctional process, hydrogen sulfide, iron (hydr)oxides, ceria, polysulfides