Affordable Access

Publisher Website

Synthesis of isoprene from formaldehyde and isobutene over phosphate catalysts

Applied Catalysis A General
Publication Date
DOI: 10.1016/j.apcata.2012.06.034
  • Prins Condensation
  • Isoprene
  • Phosphates
  • Deactivation


Abstract Vapor phase Prins condensation of isobutene with formaldehyde has been studied over boron (BP), aluminum (AlP), titanium (TiP), zirconium (ZrP) and niobium (NbP) phosphates. The catalysts were characterized by elemental analysis, X-ray diffraction, low-temperature adsorption of nitrogen, TPD of ammonia and FTIR of adsorbed pyridine. The conversion of isobutene and formaldehyde over phosphates was found to increase in the following order: BP≪AlP<TiP<ZrP<NbP, while the selectivity to isoprene showed the reverse tendency. The main side reaction was formaldehyde decomposition into carbon monoxide and dihydrogen. It is proposed that isoprene is formed on the Brønsted acid sites of the catalyst, while Mδ+Oδ− ion pairs are responsible for competitive carbon monoxide formation. The high resistance of ZrP and NbP catalysts to deactivation is accounted for by the in situ restoration of the Brønsted acid sites in the presence of water directly during the time course of the reaction.

There are no comments yet on this publication. Be the first to share your thoughts.


Seen <100 times

More articles like this

Synthesis of isobutene from synthesis gas over nan...

on Applied Catalysis A General Jan 01, 2000

Formaldehyde synthesis from methanol over silver c...

on Applied Catalysis A General Jan 01, 2003

Selective Formation of Isobutane and Isobutene fro...

on Journal of Catalysis Jan 01, 1994

Catalysis by coke deposits: synthesis of isoprene...

on Angewandte Chemie Internationa... Dec 02, 2013
More articles like this..