Bio-Oil Hydrotreatment for Enhancing Solubility in Biodiesel and the Oxydation Stability of Resulting Blends

Abstract

The major challenge for the pyrolytic conversion of lignocellulosic materials into crude bio-oil is the poor quality of the final product. Several strategies (addition of solvents, production of emulsions, and extraction with biodiesel) have been studied to improve its fuel properties. The extraction with biodiesel is an interesting solution because it allows direct utilization of some bio-oil fractions as fuels. However, fraction extracted with biodiesel is typically between 10 and 18 wt. %. In this paper we studied mild hydrotreatment of pyrolysis oil to enhance its solubility in biodiesel. The study was conducted with BTG and Amaron oils hydrotreated at temperatures between 200 and 325°C in the presence of Ru/C catalyst. Hydrotreated oils generated three phases: top oil (light hydrocarbons), middle aqueous phase and bottom heavy oil phase. Each of the phases was characterized and the content of acetic acid, phenols, aromatic compounds, and linear alkane hydrocarbons quantified. The upgraded bio-oils were more soluble in biodiesel than the crude bio-oils, obtaining blends with up to 48 and 38 wt. % for the BTG and Amaron bio-oil, respectively. Some of the fuel properties of the resulting blends are also reported here.

Hydrothermal Liquefaction Biocrude Stabilization via Hydrotreatment

“…At first, the effect of reaction temperature was investigated via conditions 1 and 2, while the effect of H 2 -to-oil ratio was assessed via condition 3. The choice of the tested operating window was made after a detailed screening of the literature relating to HTL biocrude hydrotreatment [30][31][32][33][34][35][36][37][38]. According to the literature [30][31][32][33][34][35][36][37][38], the hydroprocessing of HTL biocrude is typically performed at elevated temperatures (603−673 K) and pressures (6−9 MPa), with promising heteroatom removal.…”

“…The choice of the tested operating window was made after a detailed screening of the literature relating to HTL biocrude hydrotreatment [30][31][32][33][34][35][36][37][38]. According to the literature [30][31][32][33][34][35][36][37][38], the hydroprocessing of HTL biocrude is typically performed at elevated temperatures (603−673 K) and pressures (6−9 MPa), with promising heteroatom removal. Furthermore, due to the highly reactive oxygen-containing functional groups, at high temperatures, biocrude is susceptible to polymerization/condensation or cracking reactions, leading to fast DP build-up [39].…”

Biomass pyrolysis oil/diesel blends for a small agricultural engine

“…Pyrolysis bio-oil consisting of several hundreds of organic compounds is a very complicated mixture, and the amount of energy density is greater than the primary feedstock ranging from 5 to 20 times. The liquid properties are highly viscous and corrosive and have lower calorific value than conventional fuels (Lyu et al, 2015;Botella et al, 2018). Rajamohan et al (2022) employed bio-oil from cotton seed pyrolysis with diesel in a 4-stroke, single-cylinder diesel engine.…”

Antioxidant Additives Produced from Argan Shell Lignin Depolymerization

“…During the last years, the Thermochemical Processes Research Group (University of Zaragoza, Spain) has been focused on using different lignocellulosic feedstocks ,− for the production of natural antioxidant additives for biodiesel. The incorporation of bio-based antioxidant additives, such as bio-oil fractions, has led to excellent biodiesel oxidation stability improvements .…”