One litre of crude rubber seed oil requires 200 ml of
methanol for the acid esterification process. The rubber seed
oil is poured into the flask and heated to about 50 8C. The
methanol is added with the preheated rubber seed oil and
stirred for a few minutes. 0.5% of sulphuric acid is also
added with the mixture. Heating and stirring is continued for
20–30 min at atmospheric pressure. On completion of this
reaction, the product is poured into a separating funnel for
separating the excess alcohol. The excess alcohol, with
sulphuric acid and impurities moves to the top surface and is
removed. The lower layer is separated for further processing
(alkaline esterification).