Hydration of light Olefins : Isopropyl alcohol, s-butyl alcohol

Hydration of Light Olefins

Isopropyl alcohol, s-butyl alcohol

Isopropyl alcohol is produced through three different routes, two of which are using propylene as the starting material. One is using indirect hydration and sulphuric acid as the catalyst, the second is using direct hydration with an heterogeneous polymeric acid catalyst. The third route is using acetone as the starting material. The annual growth rate of IPA is 4-5%.

Light branched alcohols are produced by the addition of olefin and water under an acid catalyst. Isopropyl alcohol is consumed as a direct solvent for half of its production in the world, and the rest is used in various applications including surface coatings, inks, pesticides formulation, electronics applications, chemical intermediates and pharmaceutical solvents.

Secondary Butyl alcohol is mainly converted to methyl ethyl ketone (MEK or 2-butanone) which is used as a solvent in several applications such as in surface coatings, adhesives, lubricant oil dewaxing, magnetic tape and printing inks.

Hydration of propylene to IPA

Hydration of butylene-1 to SBA

Indirect hydration with sulfuric acid is the most common route to produce IPA. Olefins are hydrated to alcohols by a two stage process. Olefins are first esterified with concentrated sulfuric acid to alkyl sulfates which are then subsequently hydrolyzed. The reaction takes place at low temperature, usually below 70°C. This process is corrosive and is energy demanding for acid reconcentration and aqueous waste treatment.
The direct hydration process using a thermally stable polymeric catalyst is the preferred technology because of its product quality improvement (higher selectivity, low sulphur), lower capital spending (less acid resistant equipment needed) and less enivironmentally sensitive.
High thermal stability is required for the solid catalyst in direct hydration. Rohm and Haas has dedicated extensive research effort to developing suitable hydration catalysts for olefin hydration processes.

Recommended Catalysts

Amberlyst™ 15Wet

Conventional hydration catalyst suitable for reactive olefins such as isobutylene.

Amberlyst™ 70

Patented catalyst with the highest thermal stability on the market.

Ideal for SBA and IPA production.

The catalyst choice depends very much on the process conditions. For pricing, availability or more information please contact your Rohm and Haas representative.