Methylene bis(thiocyanate)

Methylene bis(thiocyanate) (CAS 6317-18-6), also known as methylene dithiocyanate or MBT, is a broad-spectrum biocide used to control microbial growth in industrial water systems and process fluids. Proxel MB is a recognized trade form of this active. Its primary commercial value lies in preventing bacterial and algal fouling in recirculating systems and industrial processes.

In water treatment and cooling tower systems, MBT controls slime-forming bacteria and algae that reduce heat exchange efficiency and damage infrastructure. This ensures long-term operational stability. Pulp and paper manufacturers use it to suppress microbial contamination in process water and white water circuits. Unchecked growth in these environments causes sheet defects and equipment fouling.

Oil and gas operations apply MBT to injection water and produced water systems. This inhibits sulfate-reducing bacteria responsible for microbiologically influenced corrosion in pipelines and storage tanks. Personal care formulators have incorporated it as a preservative active in rinse-off and industrial cosmetic formulations. It is selected for applications where broad-spectrum efficacy is required.

Methylene bis(thiocyanate) is supplied as a liquid concentrate, typically in aqueous solution, and as a technical-grade solid. Standard commercial supply is at technical grade for most industrial uses. Solution concentrations vary by supplier and end-use requirement. Buyers should confirm active content and formulation compatibility when evaluating supply options across different grades for their specific needs.