Question

Explain the use of the following in the manufacture of sulphuric acid by the Contact Process:
(a) Steam in the dusting tower
(b) Ferric hydroxide
(c) Coke filter
(d) Testing box
[4 MARKS]

Answer 1

Each option: 1 Mark

(a) Steam condenses on the dust particles. Hence, dust particles become heave and settle down at the bottom of the tower.
(b) Ferric hydroxide absorbs arsenic oxide which is present as an impurity and, thus, purifies the $S{O}_2$.
(c) Coke filter removes the acid mist formed in the presence of water vapour.
(d) Testing box helps to detect any impurity present in the gas. A strong beam of light is passed through the testing box. Dust particles, if present are seen in the light due to scattering of light by them.