A water condenser is attached to the soxhlet extractor and secured with clamps. All joints are lightly greased. Water outlet is checked periodically in case of pressure drop. After about 16 hours, the mantle is switched off and allowed to cool. The soxhlet is detached and dried overnight in the oven at 110oC. 8.
Filter paper is conditioned by adding de-ionised water while using vacuum pump.
The sample is removed from the soxhlet into a filter funnel. The quartz wool from the soxhlet is removed. The sample is filtered and washed with plenty of de-ionised water. The filtrate is discarded. The sample is placed in 2 litres of de-ionized water.12 mls of HCL and 30 g sodium chlorite are added.