Sulfur

Found as an element, in large underground beds Found around the rims of volcanoes. It occurs in metal ores e.g. lead sulphide Sulphur compounds also occur naturally in the fossil fuels e.g. coal

In car batteries as electrolyte In manufacture of sulphuric acid (through Contact process)

Manufacture of sulphuric acid As a food preserver; kills bacteria As a bleach in the manufacture of wood pulp for paper

Sulphur is first burned in air producing sulphur dioxide It is then mixed with more air and passed over four separate beds of catalyst, Vanadium (V) oxide, at 450°C to form sulphur trioxide It is then dissolved in concentrated sulphuric acid forming a thick fuming liquid called oleum It is then mixed carefully with water to form concentrated sulphuric acid

Catalyst: Vanadium (V) oxide Temperature: 450°C Pressure: 2atm

for making detergents as a catalyst as a dehydrating agent

For making fertilizers. To treat metals to remove oxidisation before painting. For anodising aluminium. As an acid in car batteries. For manufacturing paints, dyes and fibres. As a common laboratory reagent

powerful dehydrating agent: take water from many substances Used to dry gases (except ammonia) Powerful oxidising agent

typical strong dibasic acid: two replaceable hydrogen atoms may produce 2 series of salts – normal and acid salts

Vanadium (V) oxide

450°C

2atm

When sulfur trioxide reacts with water, a fine mist of sulfuric acid forms which does not condense easily.

Reaction is exothermic => yield of sulfur trioxide decreases with increasing temp. Too low temp, rate of reaction low => compromise

Nothing - catalyst works equally

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