Johnson Matthey has provided catalysts to reduce VOC emissions from industrial manufacturing processes since the 1960s. VOCs, NVOCs, halogenated VOCs, as well as CO, NOx and other malodorous substances can be vented or discharged from a wide range of processes and the type and concentration can vary significantly depending on the process conditions and application.
Most VOCs are emitted from solvent-based processes, but also can come from unreacted feedstock or decomposition products. Many process streams also contain inorganic material such as dust and carbonaceous PM that can influence the applicability of abatement technology.
NOx/CO Control Technology
|PM Control Technology
|Surface coating, printing, chemical and petrochemical industries, industrial and commercial processes, manufacturing processes using organic solvents, etc.
||2-way VOC Oxidation Catalyst
2-way HVOC Oxidation Catalyst & Housing
|3-way NSCR Catalyst
SCR deNOx Catalyst & Housing
|PM Trap System
Combined Catalyst & Trap System
Typical examples of VOC emissions include ethanol and acetaldehyde from bakeries, caffeine and other VOCs from coffee roasting from formaldehyde, phenols and phthalates from resin manufacturing. Petrochemical plants emit a variety of aromatic and aliphatic Chemical plants that make Purified Terephthalic Acid (PTA) resins emit methyl bromide and benzene. Printing plants emit alcohol and acetate-based compounds.
Other VOC sources include chlorinated HCs used in the manufacture of pharmaceuticals or as solvents in wooden furniture manufacture and ethylene oxide from hospital sterilization ovens.
PTA (Purified Terephthalic Acid)
Oxidation catalysts used to reduce VOC emissions from PTA (purified terephthalic acid) plants contained high amounts of precious metals such as platinum and palladium, making the catalysts fairly expensive.
So, a Johnson Matthey R&D team went to work and created a new catalyst -- SC29 PTA -- that contains no precious metals, but maintains the same performance. And at a significantly reduced cost.
Nearly all PTA is consumed in making polyester, including polyester fiber, polyethylene terephthalate (PET) bottle resin and polyester film.
PTA plants emit CO and a variety of VOCs - methyl bromide, methyl acetate, xylene, acetic acid and methanol. Together they cause smog; methyl bromide also is a stratospheric ozone depleter. Until recently, oxidation catalysts using precious metals were the only way to control these emissions.
One of the first applications for Johnson Matthey's SC29 PTA catalyst produced some incredible benefits:
- Reduced the operating temperature from 375 to 280ºC, which cut operating costs
- Replaced the existing precious metals catalyst, making the catalyst replacement cost very effective, especially since the price of precious metals has escalated
- Lowered the cost of ownership since the original catalyst containing platinum and palladium was reclaimed for $322,000, and the same volume of SC29 PTA with its sale price plus site costs for removal of the old catalyst and installation cost only about $300,000
The bottom line? The new catalyst has performed better than expected and has proven to be a real breakthrough for the PTA industry.