Enhanced Olefin Production from Renewable Aliphatic Feedstocks and Co-Fed Lignin Derivatives Using Experimental Surrogates by Millisecond Catalytic Partial Oxidation

To investigate the effect of co-fed lignin derivatives on olefin production in the catalytic partial oxidation of aliphatic feedstocks, benzene was selected as a lignin surrogate and n-hexane was selected as a renewable oil surrogate. Aromatic benzene and aliphatic n-hexane, along with the corresponding 80:20 and 50:50 molar n-hexane/benzene mixtures, were partially oxidized in millisecond contact time reactors, varying the fuel to oxygen ratio (0.8 < C/O < 2.0), the catalyst (5 wt % Pt or Rh), the support (45 or 80 pores per linear inch α-Al2O3) while maintaining constant space time (GHSV=105 h−1). The experiments indicate that the addition of benzene likely results in competitive catalytic adsorption which reduces the catalytic oxidation of n-hexane and increases production of olefins by homogeneous cracking. Under optimal conditions, selectivity to ethylene and propylene from n-hexane was increased from ∼35% using pure n-hexane to ∼65% when using a 50:50 molar mixture of benzene and n-hexane. Results indicate that the addition of lignin-derived aromatic species should increase production of olefins from catalytically reformed renewable oils.