Ammonium Sulfide may be used in the copper processing circuit to separate copper from other ores such as molybdenum. Ammonium Sulfide may be used by itself or in conjunction with NaHS (sodium hydrosulfide) in this process.
Ammonium Sulfide is a slightly alkaline liquid with a typical pH of approximately 9.5. The liquid form is typically green to reddish-yellow in color and has a strong hydrogen sulfide (rotten egg) odor. Ammonium sulfide is considered stable in normal transportation. Ammonium Sulfide are typically 45% concentration by weight and weigh approximately 8.33 pounds per U.S. gallon (1.0 gm/cc).
Ammonium Polysulfide provides a needed tool for the refinery. As refineries are being driven to lower quality crudes, problems associated with nitrogen are on the increase. A major problem is the generation of cyanide in the various thermal cracking units, primarily the catalytic cracking and coking processes.
Ammonium Polysulfide is used to chemically scavenge free cyanide which is generated in thermal cracking processes (fluidized catalytic cracking units, hydrocrackers, delayed cokers, fluidized cokers, etc.) in refineries, converting it to thiocyanide, which is easily handled in the refineries' water treatment facility. If the free cyanides are not scavenged, they can contribute to corrosion within the units , downstream units, and/or send the free cyanide to the refinery's waste water plant.
Ammonium Bisulfite is a very versatile product and is used in many process applications in a wide range of industries for continuous cyanide removal from industrial waste effluents. Successfully used by mines as a liquid alternative to SO 2 gas in Inco's SO 2 /Air process, providing similar performance with the safety of a water-based material. Ammonium Bisulfite used in a wide range of applications, including:
• Oxygen scavenging
• Sugar beet processing
• Caramel coloring
• Cyanide reduction in precious-metals mining process
• Oxidation inhibitor