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To realize the resource and high-value utilization, a new approach, named bagasse lignin (BL) used to produce aryl oxygen-containing compounds by catalytic pyrolysis over perovskite, was proposed. LaTi0.2Fe0.8O3(LTF) samples prepared by the sol-gel method (SG) and the solid-state reaction method (SS) were characterized. The catalytic action on BL pyrolysis was performed by the test of TG-DTG and the evaluation of the fixed bed micro-reactor, the components and contents of the products were determined. The results show that LTF samples have cubic perovskite phase, LTF prepared by SG (LTF-SG) is porous with larger specific surface area than LTF prepared by SS (LTF-SS). During the pyrolysis of BL, the addition of LTF lowers the pyrolysis temperature and the activation energy, the contents of CO2and CO in gaseous products reduce by 4.6%–8.0% and 30.7%–34.3%, respectively, the total content of aryl oxygen-containing compounds (including phenolics, guaiacols, syringols and phenylates) in liquid products increases from 62 wt% to more than 72 wt%, and LTF-SG shows better catalytic performance. LTF samples have nice phase and catalytic stabilities for BL pyrolysis after five successive redox cycles.

A series of LaM0.2Fe0.8O3(M = Fe, Cu, Al, Ti) samples synthesized by the sol–gel method were used to catalyze the pyrolysis of bagasse alkali lignin (BAL) to produce aryl oxygen-containing compounds. The effects of doping metal ions in the B-site of LaFeO3were investigated by X-ray diffraction, scanning electron microscopy, Brunauer–Emmett–Teller, and X-ray photoelectron spectrometer. Furthermore, the catalytic pyrolysis performances of the perovskites were evaluated by thermogravimetric analysis and the fixed-bed microreactor, and the gaseous and liquid pyrolysis products were analyzed by GC and gas chromatography/mass spectrometry (GC/MS), respectively. The results indicated that the perovskites have a cubic crystal phase, porous structure, and large specific surface area. After doping Cu, Al, and Ti ions in the B-site of perovskites, the grain sizes were refined, the performance of catalyzing BAL pyrolysis was improved, and the yields of liquid pyrolysis products increased by 24.1–39.1%. The selectivities of CO2and CO in gaseous products decreased by 5.8–16.3 and 26.0–34.8%, respectively, which resulted from the inhibition of decarboxylation and decarbonylation. The total selectivities of target products, i.e., aryl oxygen-containing compounds (including phenolics, guaiacols, syringols, and phenylates) obtained from BAL pyrolysis catalyzed using perovskites were all greater than 74 wt %, which was higher than that obtained from the pyrolysis of pure BAL (62 wt %) in the absence of catalyst. After 5 cycles of redox reaction, the perovskite still showed a well-maintained structural and catalytic stability.

LaTi0.2Fe0.8O3(LTF) was prepared by the sol-gel method, and the effects of calcination temperature on the structure and properties were investigated. A new method of preparing aryl oxygen-containing compounds from bagasse lignin (BL) by the catalytic pyrolysis over LTF was proposed. The results show that LTF has cubic crystal phase and porous structure and its optimal calcination temperature is 800 °C (LTF-800). In the test for catalytic pyrolysis of BL, with the addition of LTF-800, the yield of liquid product reaches the maximum; the contents of phenolics, guaiacols, syringols, phenylates and furans increase obviously, while those of benzenes, esters and carboxylic acid decrease. The total content of aryl oxygen-compounds (including phenolics, guaiacols, syringols and phenylates) in liquid product is more than 74 wt% with the addition of LTF-800, larger than that obtained by single BL pyrolysis (62 wt%). LTF could avoid oxygen-containing functional groups from being excessively destroyed. It has nice regeneration performance by controlled combustion of char even after 5 cycles.