Convenient synthesis of methylene bisthiocyanate as microbiocide

Methylene bisthiocyanate (MBT) is used as a biocide in the leather making industry. Commercial biocidal formulations containing a blend of 10% MBT (Methylene bisthiocyanate) and 10% TCMTB (2-Thiocyanomethylthio)-benzothiazole are available. This blend of active ingredients combine the rapid antimicrobial action of MBT with the fungicidal properties of TCMTB. Such biocides are suitable for use over a wide range of tannery applications including the soaking and pickling stages. This paper reports on a simple and cleaner technology of the synthesis of MBT by using non toxic and non hazardous raw materials and belongs to the modern concept of environmentally friendly low wastes or non wastes technology (LWNWT). From the workers health and safety point of view raw materials such as sodium thiocyanate, water, phase transfer catalyst (Benzyl trithylammonium chloride) and halogenating agent (Bromochloromethane, ethylene bromide, methylene chloride) are used which are non hazardous and non toxic. MBT is characterized by conventional methods, IR 1HNMR and mass spectral data.