Oxidation of Cyclohexane, Cyclohexanone, and Cyclohexanol to Adipic Acid by a Non-HNO3 Route over Co/Mn Cluster Complexes

Simple and Green Adipic Acid Synthesis from Cyclohexanone and/or Cyclohexanol Oxidation with Efficient (NH4)xHyMzPMo12O40 (M: Fe, Co, Ni) Catalysts

“…The obtained results (Table 4) show that the addition of alcohol to ketone has negative effect on AA formation regardless of the catalyst composition. This observation has already been reported in the presence of methyleyhylcetone as oxidant and Co/Mn based complexes as catalysts [3] and hydrogen peroxyde as oxidant and Keggin phosphomolybdic salts substituted with cobalt or nickel as catalysts [18,19]. The following sequence was observed: YAA (cyclohexanone) > YAA (cyclohexanone / cyclohexanol) > YAA (cyclohexanol).…”

“…So, the development of catalytic oxidation systems with environmentally benign oxidants as air [1], molecular oxygen [2,3], or hydrogen peroxide [4][5][6] that can reduce the use of toxic and hazardous substances is the sought aim. It was noted that with these oxidants, the active oxygen species content is high with 100% for molecular oxygen and 47% for hydrogen peroxide.…”

Zeolite-Y entrapped bivalent transition metal complexes as hybrid nanocatalysts: density functional theory investigation and catalytic aspects

“…The former band (ϕ→ϕ*) undergoes hypsochromic shift in Cu(II) and bathochromic shifts in Mn(II) and Co(II) entrapped complexes, resulting from chelation of the ligand with the transition metal. In the electronic 4 T 1g (F)→ 4 T 1g (P), and MLCT transitions of an octahedral geometry around the metal ion, respectively. The absorption spectrum of [Ni (SFCH)·3H 2 O]-Y exhibits two bands at 680 and 242 nm that may be attributed to 3 A 2g → 3 T 1g (P) (ν 3 ) and 3 A 2g → 3 T 1g (F) (ν 2 ) transitions, respectively (33).…”

“…As a result, heterogenization of homogeneous catalysts has become a significant approach for obtaining supported catalysts that sustain the active catalytic sites of the homogeneous analog (1,2). The encapsulation of the transition metal complexes inside the nanopores of zeolite is one of the heterogenization methods and also is a theme of contemporary research (3)(4)(5)(6)(7). Heterogenization is accomplished either by entrapping the metal complex within the zeolite nanocavities or by anchoring and/or tethering them to inert supports (8).…”

Influence of Organic Additives on Catalysts of Liquid-Phase Cyclohexane Oxidation

“…Increase of selectivity and conversion values of this process by at least 1 % will significantly reduce the expense coefficients for raw materials and energy. Therefore, the creation of efficient catalytic systems for homogeneous catalytic oxidation of cyclohexane remains relevant [2,7,8].…”