Rubber Lining for ALF3 Reactor

I have a query for suitable rubber material for our ALF3 Reactor lining as the existing rubber lining is not giving sufficient life. In this regard , I am sending the available details for your reference.

Description of Process-

The process consists of reacting Hydrofluosilicic acid,H2SiF6 of 17 to 20% concentration with dry Aluminium Hydroxide, Al(OH)3, to produce AluminiumFluoride according to the following reaction:

H2SiF6 + 2Al(OH)3 = 2AlF3 + SiO2 + 4H2O.

This reaction is exothermic and max. temp is 110 deg C . This reaction takes place inside the Reactor which is a MS Rubberlined vessel with an agitator running at 100 rpm. Presently the vessel is lined with Butyl Rubber 5 mm, shore hardness 65D .

Tank Dimension

a) Tank Dia. - 1850 mm

b) Tank length - 3000 mm

Kindly suggest suitable rubber material , which can give a better life.