Selective catalytic degradation of a lignin model compound into phenol over transition metal sulfates

Abstract

Transition metal salts were employed as the catalysts to improve the selective degradation of the a-O-4 lignin model compound (benzyl phenyl ether (BPE)) in the solvothermal system. The results concluded that most of the transition metal salts could enhance BPE degradation. Among which, NiSO 4 $6H 2 O exhibited the highest performance on BPE degradation (90.8%) for 5 h and phenol selectivity (53%) for 4 h at 200 C. In addition, the GC-MS analysis indicated that the intermediates during BPE degradation included a series of aromatic compounds, such as phenol, benzyl methyl ether and benzyl alcohol. Furthermore, the mechanisms for BPE degradation and phenol selectivity in the NiSO 4 $6H 2 O system involved the synergetic effects between the acid catalysis and coordination catalysis, which caused the effective and selective cleavage of the C-O bonds.Fig. 3 (a) Effect of reaction time on BPE degradation; (b) the hydrogen ion concentration during the process. (c) X-ray diffraction pattern for recovered catalysts. Condition: 300 mg BPE, 1.4 mmol NiSO 4 $6H 2 O, 20 mL methanol, 200 C. 3016 | RSC Adv., 2020, 10, 3013-3019 This journal is

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