Stretford process

The Stretford process was developed to remove hydrogen sulfide (H₂S) from town gas. It was the first liquid phase, oxidation process for converting H₂S into sulfur to gain widespread commercial acceptance. [cite web |authorlast=Nagl |authorfirst=Gary J |title=The State of Liquid Redox |work=Gas Technology Products |publisher=Merichem Company |date=2005 |url=http://www.gtp-merichem.com/support/technical_papers/liquid_redox.php |accessdate=2007-05-23] Developed by Tom Nicklin of the North-Western Gas Board (NWGB) and the Clayton Aniline Company, in Manchester, England, during the 1940s, the name of the process was derived from the location of the NWGB's laboratories, in Stretford.

The process uses reduction-oxidation (redox) chemistry to oxidise the H₂S into elemental sulfur, in an alkaline solution containing vanadium as an oxygen carrier. [cite web |title= Process Screening Analysis of Alternative Gas Treating and Sulfur Removal for Gasification |publisher=SFA Pacific |date=2002 |url=http://www.netl.doe.gov/technologies/coalpower/gasification/pubs/pdf/SFA%20Pacific_Process%20Screening%20Analysis_Dec%202002.pdf | format= PDF | accessdate= 2007-05-23]

The process was licensed by NWGB, which later became part of British Gas plc. Many Stretford plants were built worldwide. The first USA plant, in Long Beach, California is commemorated by a plaque outside the refinery, near to the Queen Mary.

ee also

*Sour gas
*Hydrodesulfurization

References