On the hydroisomerization activity of nickel-substituted mica montmorillonite

Three-layer sheet aluminosilicates when exchanged into the acidic form are far less active as hydroisomerization catalysts than zeolites having a comparable surface proton density. However, introducing Ni2+ or Co2+ into the octahedral positions of the Al3+ layer in synthetic beidellite results in hydroisomerizations catalysts of an activity similar to that of a zeolite. From pyridine-poisoning experiments and
measurements it can be concluded that this increased activity stems from the increased acidity of the resulting NiSMM (Ni-synthetic mica montmorillonite) clay due to reduction of Ni.