Dimethyl disulfide (DMDS) is an organic chemical compound with the molecular formula CH3SSCH3
which is the simplest disulfide. It is a flammable liquid with an unpleasant, garlic-like odor. Dimethyl
disulfide is a widespread natural odoriferous compound emitted from many sources such as
bacteria, fungi, plants and animals. It is an oxidation product of methanthiol in air and is Used as a
solvent and a pesticide intermediate.
Food use: DMDS is used as a food additive in onion, garlic, cheese, meats, soups, savory flavors, and
fruit flavors. Industrially, DMDS is used in oil refineries as a sulfiding agent. DMDS is also an effective
soil fumigant in agriculture, registered in many states in the U.S. as well as globally. In this capacity,
DMDS is an important alternative in replacing methyl bromide, which is being phased out, however
less effective than the former. This pesticide is marketed as "Paladin" by Arkema. DMDS is used to
alpha substitute 2-methylfuran-acrolein to produce a food stuff used in concentrations from 0.02
ppm up to 50 ppm.
Industrial use: DMDS is a stable pale-yellow liquid which works as an effective product for sulfiding
hydroprocessing catalysts because of its high sulfur content and low decomposition temperature.
Most refineries utilize DMDS instead of other sulfur spiking agents for catalyst sulfiding because it
has more sulfur per pound than dimethyl sulfide (DMS) or di-tertiary-butyl polysulfide (TBPS). Once
injected to a hydrotreater or hydrocracker, DMDS decomposes to form H2S. The H2S reacts with the
metal oxides on the catalyst, converting them to the active metal sulfide form.
DMDS also works as an effective product for operators in the petrochemicals industry who must
protect their steam-cracking coils against the formation of coke and carbon monoxide.
DMDS is utilized in the preparation of 4-(methylthio)phenol which is used in the production of
various pesticides. DMDS and chlorine are reacted with borontriflouride phenolate to produce 4-
(methylthio)phenol. Thiophene and DMDS are blended with combustible hydrocarbon fuel gas to
impart a gassy odor to the fuel gas.