Hydrotreating of Jatropha-derived Bio-oil over Mesoporous Sulfide Catalysts to Produce Drop-in Transportation Fuels

Abstract

The bio-oil was largely produced by thermal pyrolysis of Jatropha-derived biomass wastes (denoted as Jatropha bio-oil) using a pilot plant with a capacity of 20 kg h-1 at Thailand Institute of Scientific and Technological Research (TISTR), Thailand. Jatropha bio-oil is an unconventional type of bio-oil, which is mostly composed of fatty acids, fatty acid methyl esters, fatty acid amides, and derivatives, and consequently, it contains large amounts of heteroatoms (oxygen ~20 wt.%, nitrogen ~ 5 wt.%, sulfur ~ 1000 ppm.). The heteroatoms, especially nitrogen, are highly poisonous to the metal or sulfide catalysts for upgrading of Jatropha bio-oil. To overcome this technical problem, we reported a stepwise strategy for hydrotreating of 100 wt.% Jatropha bio-oil over mesoporous sulfide catalysts (CoMo/γ-Al2O3 and NiMo/γ-Al2O3) to produce drop-in transport fuels, such as gasoline- and diesel-like fuels. This study is very different from our recent work on co-processing of Jatropha bio-oil (ca. 10 wt.%) with petroleum distillates to produce a hydrotreated oil as a diesel-like fuel. Jatropha bio-oil was pre-treated through a slurry-type high-pressure reactor under severe conditions, resulting in a pre-treated Jatropha bio-oil with relatively low amounts of heteroatoms (oxygen < 20 wt.%, nitrogen < 2 wt.%, sulfur < 500 ppm.). The light and middle distillates of pre-hydrotreated Jatropha bio-oil were then separated by distillation at a temperature below 240 °C, and a temperature of 240–360 °C. Deep hydrotreating of light distillates over sulfide CoMo/γ-Al2O3 catalyst was performed on a batch-type high-pressure reactor at 350 °C and 7 MPa of H2 gas for 5 h. The hydrotreated oil was a gasoline-like fuel, which contained 29.5 vol.% of n-paraffins, 14.4 vol.% of iso-paraffins, 4.5 vol.% of olefins, 21.4 vol.% of naphthene compounds and 29.6 wt.% of aromatic compounds, and little amounts of heteroatoms (nearly no oxygen and sulfur, and less than 50 ppm of nitrogen), corresponding to an octane number of 44, and it would be suitable for blending with petro-gasoline. The hydrotreating of middle distillates over sulfide NiMo/γ-Al2O3 catalyst using the same reaction condition produced a hydrotreating oil with diesel-like composition, low amounts of heteroatoms (no oxygen and less than 50 ppm of sulfur and nitrogen), and a cetane number of 60, which would be suitable for use in drop-in diesel fuel.

Impact of Coprocessing Biocrude with Petroleum Stream on Hydrotreating Catalyst Stability

“…Xing et al reported the deactivation of catalyst in its HDS and HDN activity and selectivity during coprocessing a woody biomass-derived HTL biocrude and without further explanation of the deactivation mechanism. As for the coprocessing of fast pyrolysis oils from woody biomass, it is known that the instability of regular fast pyrolysis bio-oil could lead to carbonaceous species formation and reactor plugging, and therefore, most coprocessing studies use upgraded bio-oil, such as hydrotreated bio-oil. , Other studies also showed that coprocessing lignocellulosic bio-oils with petroleum distillates leads to increased coke formation and gradual sulfur leaching. , When coprocessing animal fat with gas oils, the high amounts of inorganic impurities, such as silicon, phosphorus, and alkali and alkaline earth metals, represent a risk of catalyst poisoning as one of the main reasons for catalyst deactivation. , …”

“…In petroleum refineries, catalyst deactivation has been well studied for hydrotreating processes. , The deactivation is largely a result of simultaneous coke and metal deposition and is affected by several factors, including catalyst type, feedstock properties, operating conditions, and reactor design. , The impact of biomass-derived oil and crude intermediates on coprocessing catalyst stability has been reported. − For instance, introducing a lignocellulosic HTLbiocrude into petroleum gas oil showed premature and faster catalyst deactivation . Studies on coprocessing lignocellulosic bio-oils with petroleum distillates showed that the high oxygen content in bio-oil leads to increased coke formation and a gradual sulfur leaching, resulting in catalyst deactivation and process deficiency. , In addition, when coprocessing animal fat with gas oils, the high amounts of inorganic impurities, such as silicon, phosphorus, and alkali and alkaline earth metals, represent a risk of catalyst poisoning as one of the main reasons for catalyst deactivation. , A clear understanding of the deactivation behavior particularly caused by biocrudes is highly desirable and critical to improving hydrotreating catalysts and processes to enable coprocessing renewable feedstocks and to incorporate biogenic carbon in fuels.…”

Effect of Pd Precursor Salts on the Chemical State, Particle Size, and Performance of Activated Carbon-Supported Pd Catalysts for the Selective Hydrogenation of Palm Biodiesel

“…However, the product selectivity for mono-FAME, cis -mono-FAME, and sat-FAME as a function of reaction time over Cl-containing and Cl-free Pd catalysts remained nearly unchanged, particularly those related to high poly-FAME conversions. This result indicated that the hydrogenation of poly-FAME components over the Cl-containing Pd particles was slightly facilitated, presumably due to the Pd surface being slightly electron-deficient owing to the high electronegativity of the Cl species [ 56 , 59 , 60 , 61 ]. However, the activity and selectivity of Pd/AC catalysts in the partial hydrogenation of a commercial palm-BDF were predominately influenced by the sizes of Pd particles.…”

Differential Occurrence of Cuticular Wax and Its Role In Leaf Tissues of Three Edible Aroids of Northeast India

“…1). In an aliphatic chain (sul de) or with a double bond with oxygen (sulfoxide), sulfur induces a glossy leaf surface by accumulating bio-oil and bio-wax, which act as a natural sun protector 40 .…”