Separation of Sulfur from Liquid or Vapor

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Potable Water

Sulfur oxides as sulfuric acid, sulfate and sulfite are anions and readily removed with anion exchange resins. For potable water at neutral pH, a high capacity strong base anion exchange resin like AMBERLITE™ PWA15 Resin is recommended.

This resin may be subject to drinking water application restrictions in some countries. Please check the application status before use and sale. For more information see our regulatory information.

Wastewater

When present as acids, sulfate and sulfite can be removed from wastewater with acid absorber such as DOWEX MARATHON™ WBA Resin, or for higher capacity, DOWEX MARATHON WBA 2 Resin.

For pH-neutral wastewater streams, a strong base anion exchanger like DOWEX™ 21K XLT Resin is recommended. Here, the resin will remove all of the anions along with the sulfate and sulfite.

For streams that have a high organic content and are prone to surface fouling, DOWEX MARATHON 11 Resin or AMBERLITE™ IRA458 Cl Resin is recommended.

Selective Sulfate Removal from Brine

Selective removal of sulfate from brine has been described using a metal hydroxide loaded ion exchange resin.1 2 3

This approach is particularly valuable in high salt streams like brines. Dow recommends a catalyst, AMBERLYST™ 15 Catalyst, for this application.

Hydrogen Sulfide Removal

The reduced form of sulfur, H2S, acts as a weak acid so it can be captured from water or air with a weak base anion resin such as DOWEX MARATHON™ WBA Resin, or for higher capacity, DOWEX MARATHON WBA 2 Resin.

Mercaptan Removal

Mercaptans are organo-sulfur compounds that are typically not charged. These compounds can be captured by an adsorption mechanism with DOWEX OPTIPORE™ L493 Polymeric Adsorbent Resin for liquid streams or DOWEX OPTIPORE V493 Polymeric Adsorbent Resin for vapor streams.

Sulfate Removal from Injection Water in Offshore Oil Production

Barium (Ba) and strontium (Sr) minerals, often present in sub-sea reservoirs, will precipitate with sulfate ions introduced via seawater injection and reduce formation permeability and potentially scale piping, so it is critical to remove sulfate prior to injection. FILMTEC™ SR90 Nanofiltration Elements are an excellent choice to selectively separate sulfate ion from seawater to protect valuable hydrocarbon reservoirs. As an additional benefit, this treatment helps prevent souring.

1 US Patent 4,415,677 – "Removal of sulfate ions from brine using composite of polymeric zirconium hydrous oxide in macroporous matrix" Lee, John M.; Bauman, William C. Assignee: The Dow Chemical Company (1983).

2 US Patent 4,415,678 – "Removal of sulfate ions from brine using amorphous polymeric zirconium oxide formed within a macroporous polymer matrix" Lee, John M.; Bauman, William C. Assignee: The Dow Chemical Company (1983).

3 "Method of purification of salt solution for electrolysis" by Oohara, C.; Matsuoka, T.; Kishi, T.; Okuno, T. of Chlorine Engineers Corp., Ltd. European Patent Application EP 0 987 221 A1 (1999).

Sulfur occurs widely in nature in the oxidized and reduced forms.