1) Describe the manufacture of Sulfuric Acid by the Contact process
Sources of 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.
- 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