Phosphourus Pentasulfide 

*Short tons per year of phosphorus pentasulfide, P₂S₅ basis. Commercial production is by measured addition of molten phosphorus to a reactor containing molten sulfur.

Monsanto spun-off its industrial chemicals operations as Solutia, in 1997.

Zeneca Inc. discontinued its Mt. Pleasant, Tenn. phosphorus pentasulfide operation, rated at 20,000 tons per year, in 1998.

Rhodia Inc. closed its phosphorus pentasulfide production, 20,000 short tons of capacity, at Morrisville, Pa., in 2000. Also in 2000, Peak Chemicals, a private equity-backed company, took over the former FMC phosphorus pentasulfide operation at Lawrence, Kan. The Federal Trade Commission required that FMC sell the plant when the company merged its phosphates business with Solutia to form Astaris.

Profile last published 1/27/97; this revisions, 9/02/02.

DEMAND
2000: 53,900 short tons; 2001: 54,100 short tons; 2005: 55,000 short tons, projected. Demand equals production plus imports (2000: 0 short tons; 2001: 100 short tons) less exports (2000: 6,000 short tons; 2001: 5,100 short tons).

GROWTH
Historical (1996 - 2001): -2.4 (negative) percent per year; future: 0.4 percent per year through 2005.

PRICE
Historical (1996 - 2001): High, $0.71 per pound, seller's tote bins, works; low, $0.67, same basis. Current: $0.71, same basis.

USES
Lubricating oil and grease additives (mainly zinc dialkyldithiophosphates (ZDDP)) 68 percent; organophosphorus insecticides (such as acephate, chloropyrifos and terbuphos), 24 percent; ore flotation, 2 percent; miscellaneous, 6 percent.

STRENGTH
The most widely used phosphorus containing oil additives are ZDDPs. These additives are used as antioxidants, as antiwear and extreme-pressure agents and to a lesser extent as corrosion inhibitors. ZDDP compounds protect metal surfaces by forming a phosphorus based coating that prevents direct metal-to-metal contact. Finished motor oils currently contain an average of about 1 percent ZDDP by weight. The consumption of phosphorus pentasulfide for ZDDP produced for U.S. consumption appears to have stabilized and little change is expected during the forecast period to 2005, as U.S. demand for lubricants is expected to show only flat to modest growth during this period.

WEAKNESS
The phosphorus pentasulfide market has been shrinking since the late 1970s as a result of decline in its two major application segments - zinc dialkyldithiophosphate (ZDDP) for motor lubricating oils, and insecticides. Automakers, concerned about possible contamination of catalytic converters by phosphorus, pushed for motor oils with lower phosphorus content. In addition, there has been a decrease in U.S. ZDDP exports due to displacement by local ZDDP production overseas. And, ending production of the of the pesticides malathion and parathion severely curtailed phosphorus pentasulfide consumption in this sector. In 1979 43,600 tons of phosphorus pentasulfide were consumed for pesticides. Last year, that consumption was down to 13,000 tons. Significant-volume pesticide products, derived from phosphorus pentasulfide, are still manufactured and include chlorpyrifos, diazinon, acephate and terbufos. This market segment, however, is anticipated to be flat through the forecast period.

OUTLOOK
No significant new applications for phosphorus pentasulfide appear to be developing and well-established markets are either flat or in decline. Aggregate demand growth is forecast at 0.4 percent, through 2005.