Preparation of Co- or Mn-substituted LTL zeolites and their catalytic properties in cyclohexane oxidation

Co- or Mn-substituted LTL zeolites were hydrothermally synthesized by a novel organic-ligand-assisted method. XRD, UV-Vis DRS, XPS, and EPR techniques verified that the Co and Mn ions were incorporated into the zeolite framework. No organic species were retained in as-synthesized Co or Mn-LTL zeolites, which resulted in porous materials without calcination. In the oxidation of cyclohexane with tert-butyl hydroperoxide (TBHP), the Co-LTL and Mn-LTL gave a 40%-48% KA oil (cyclohexanone and cyclohexanol) yield as well as nearly 100% TBHP conversion under mild reaction conditions. The reactions were confirmed to be heterogeneous and to have proceeded catalytically. No loss of catalytic activity or leaching of metal active sites ions were observed during 4 reuses.