Influence of CeO2 Addition to Ni–Cu/HZSM-5 Catalysts on Hydrodeoxygenation of Bio-Oil

Abstract

Hydrodeoxygenation (HDO) of bio-oil is a method of bio-oil upgrading. In this paper, x%CeO2–Ni–Cu/HZSM-5 (x = 5, 15, and 20) was synthesized as an HDO catalyst by the co-impregnation method. The HDO performances of x%CeO2–Ni–Cu/HZSM-5 (x = 5, 15, and 20) in the reaction process was evaluated and compared with Ni–Cu/HZSM-5 by the property and the yield of upgrading oil. The difference of the chemical composition between bio-oil and upgrading oil was evaluated by GC-MS. The results showed that the addition of CeO2 decreased the water and oxygen contents of upgrading oil, increased the high heating value, reduced acid content, and increased hydrocarbon content. When the CeO2 addition was 15%, the yield of upgrading reached the maximum, from 33.9 wt% (Ni–Cu/HZSM-5) to 47.6 wt% (15%CeO2–Ni–Cu/HZSM-5). The catalytic activities of x%CeO2–Ni–Cu/HZSM-5 (x = 5, 15, and 20) and Ni–Cu/HZSM-5 were characterized by XRD, N2 adsorption–desorption, NH3-Temperature-Programmed Desorption, H2-Temperature-Programmed Reaction, TEM, and XPS. The results showed that the addition of CeO2 increased the dispersion of active metal Ni, reduced the bond between the active metal and the catalyst support, increased the ratio of Bronsted acid to total acids, and decreased the reduction temperature of NiO. When the CeO2 addition was 15%, the activity of catalyst reached the best. Finally, the carbon deposition resistance of deactivated catalysts was investigated by a Thermogravimetric (TG) analysis, and the results showed that the addition of CeO2 could improve the carbon deposition resistance of catalysts. When the CeO2 addition was 15%, the coke deposition decreased from 41 wt% (Ni–Cu/HZSM-5) to 14 wt% (15%CeO2–Ni–Cu/HZSM-5).

Dual-Oriented Selectivity Switching for Highly Efficient Biomass Upgrading via Selective C–O Bond Activation

“…Peaks at 44.6, 52.0, and 76.6° assigned to the Ni metal phase (JCPDS no. 88–2326) were observed in the spent 10Ni/HZ5 (150) sample, which were consistent with the results of X-ray photoelectron spectroscopy (XPS) analysis of Ni species before and after reactions (Figure S4) that showed the existence of metallic Ni 0 active sites . The textural properties of such spent catalysts could be largely recovered after regeneration (calcined in air at 500 °C for 2 h), suggesting a good nature of the structural stability (Table S12).…”

“…88−2326) were observed in the spent 10Ni/HZ5 (150) sample, which were consistent with the results of X-ray photoelectron spectroscopy (XPS) analysis of Ni species before and after reactions (Figure S4) that showed the existence of metallic Ni 0 active sites. 31 The textural properties of such spent catalysts could be largely recovered after regeneration (calcined in air at 500 °C for 2 h), suggesting a good nature of the structural stability (Table S12). For the reducibility of the samples, as expected, H 2temperature-programmed reduction (H 2 -TPR) excluded the presence of reducible species in pure HZ5 (150) zeolite (Figure 3b).…”

Prediction of Higher Heating Values in Bio-Oil from Solvothermal Biomass Conversion and Bio-Oil Upgrading Given Discontinuous Experimental Conditions

“…This resulted in initial numbers of 172 and 2,392 documents, respectively, that were then screened to make sure they reported as many of the process variables noted in Table . After the screening process, a total of 15 and 29 papers were selected that fit the criteria, resulting in a total of 175 and 211 data points, respectively. − Studies that were not selected were deemed unfit due to noncompatible methodologies or underreporting of results and process conditions. This search for data and processing centers exclusively on changes to HHV or resulting HHV in BO from experiments but not directly on the chemical species found in the BO, which is beyond the scope of this work.…”