Sulfur dichloride

Photo by sciencemadness user len1

Sulfur dichloride (SCl₂) is a foul smelling red liquid created through the reaction of sulfur and chlorine.

Properties

Chemical

Disulfur dichloride reacts with water to form sulfur dioxide and hydrochloric acid, so an open container wiill produce thick white fumes as it reacts with moisture in the air. Sulfur dichloride slowly converts into disulfur dichloride.

Sulfur chlorides can be used to produce thionyl chloride.

Physical

SCl₂ has a highly unpleasant odour, as well as producing HCl and SO₂ which are also highly unpleasant to breathe in.

It is a bright red liquid with viscosity similar to water.

Availability

Due to air instability and pressure build-up from decomposition to the monochloride, disulfur dichloride is generally not avaliable to buy.

Chlorine is produced through TCCA + HCl and dried over CaCl₂ before being passed into the molten sulfur

Preparation

SCl₂ distills over as chlorine is passed over molten sulfur. This reaction may also produce disulfur dichloride.

Both sulfur and chlorine are common chemicals in a home laboratory but the synthesis of sulfur dichloride is complicated as it requires simultaneous distillation while gassing the sulfur with the chlorine which requires moderately complicated glassware such as two necked flasks or a very well improvised setup.

An older method involves the reaction of sulfuryl chloride (which can be made by reacting dry sulfur dioxide and chlorine gas) with anhydrous zinc sulfide, in the presence of aluminium chloride.

Projects

• Make thionyl chloride
• Make sulfur nitride
• Make anhydrous metal chlorides

Handling

Safety

Sulfur dichloride is extremely toxic and corrosive and proper protection must be worn when working with the compound. Work should be performed in a fumehood.

Storage

SCl₂ should be stored in a sealed container, in a dry cold place. As it slowly decomposes over time, it's best to open the bottle from time to time to release the pressure.

Disposal

Reaction with water destroys the compound, and this can be effective if done outside or in an area capable of safely removing the sulfur dioxide. Aqueous sodium hydroxide solutions can also be used. Calcium hydroxide suspension is also a good choice.

See also

• Disulfur dichloride