	exxon xon south african unit uired by zenex zenex oil pty ltd said it uired the interests of esso south africa the local subsidiary of exxon corp xon and will use up to mln rand in profits to finance educational and social programs the profit scheme will begin after zenex has paid exxon an undisclosed purchase price for esso zenex chairman john truscott said in a statement the uisition follows the exxon withdrawal from south africa announced last december reuter 
