Renewable Diesel Production from the Hydrotreating of Rapeseed Oil with Pt/Zeolite and NiMo/Al₂O₃ Catalysts

Abstract

As an alternative way to produce diesel hydrocarbons, the hydrocracking of rapeseed oil was studied on three different types of bifunctional catalysts: Pt/H-Y, Pt/H-ZSM-5, and sulfided NiMo/γ-Al 2 O 3 . Experiments were carried out in a batch reactor over a temperature range of 300-400 °C and initial hydrogen pressures from 5 to 11 MPa. The reaction time was limited to 3 h to prevent a high degree of cracking. The Pt-zeolite catalysts had a strong catalytic activity for both cracking and hydrogenation reactions, and therefore a higher severity was required to reach a relatively high oil conversion into liquid hydrocarbons. With dependence on the activity of the acid sites of the catalysts, the results show a trade-off between the yield of green diesel and the degree of isomerization, which had a direct effect on the cold properties of the diesel. Among the three catalysts, hydrocracking on Ni-Mo/γ-Al 2 O 3 gave the highest yield of liquid hydrocarbons in the boiling range of the diesel fraction, i.e., green diesel, containing mainly n-paraffins from C 15 to C 18 , and therefore with poor cold flow properties. While for both zeolitic catalysts, hydrotreating of rapeseed oil produced more iso-than n-paraffins in the boiling range of C 5 to C 22 , which included significant amounts of both green diesel and green gasoline. The gas chromatography (GC) analysis of the gaseous phase revealed the presence of mainly CO 2 , CO, propane, and remaining hydrogen. It was observed that both pressure and temperature play an important role in the transformation of triglycerides and fatty acids into hydrocarbons.

Catalytic Deoxygenation of Hexadecyl Palmitate as a Model Compound of Euglena Oil in H2 and N2 Atmospheres

“…As shown in Figure 7, the yield of C 1 -C 16 hydrocarbons increased to 90.2% after reaction for 2 h, and then decreased slightly with prolonging reaction time due to the formation of light hydrocarbons (<C 9 ). On the whole, the Pd/Mg(Al)O catalyst provided a high catalytic performance for the catalytic deoxygenation of C 15 in each autoclave reactor was finished in an hour. The products were analysed to determine the C15H31COOC16H33 conversion and the C10-C16 hydrocarbon yield at that reaction time.…”

“…)-supported catalysts possess high activities for the deoxygenation of triglycerides and fatty acids in H 2 atmosphere [15][16][17]. However, the deoxygenation of triglycerides in N 2 atmosphere (without H 2 ) is an important subject, because H 2 is expensive and may be difficult to obtain in areas of vegetable and algae cultivation.…”

“…This method, known as "solid phase crystallization" (SPC), is important in the preparation of highly active metal-supported catalysts [27][28][29][30][31][32][33][34][35]. In this study, Pd 2+ Figure 5 shows the flame ionization detector-gas chromatography (FID-GC) charts of C 15 Figure 5B, the reactant (C 15 H 31 COOC 16 H 33 ) peak is not observed in the GC chart after reaction at 300 • C for 2 h. The liquid products were almost saturated hydrocarbons n-C 16 H 34 and n-C 15 H 32 . By calculating the amount of each component in the product using the GC chart, the molar ratio of n-C 16 H 34 to n-C 15 H 32 in the liquid product was found to be 4.3.…”

Production of Bio-Hydrogenated Diesel by Hydrotreatment of High-Acid-Value Waste Cooking Oil over Ruthenium Catalyst Supported on Al-Polyoxocation-Pillared Montmorillonite

“…For converting vegetable oil to bio-hydrogenated diesel (BHD), two types of effective catalysts have been reported for the hydrotreatment process: noble metal catalysts (Pd, Pt, etc.) [17][18][19][20][21], and desulfurized catalysts (sulfided Ni-Mo, Co-Mo, Ni-W, Co-W, etc.) [21][22][23][24].…”

“…The yield of C 15 -C 18 n-paraffins usually has been stated in the literature for the hydrotreatment of vegetable oil and it seems that the amount of C 15 -C 18 n-paraffins determines the quality of BHD fuel [18][19][20][21][22]. Actually, an extreme amount of C 15 -C 18 n-paraffins give BHD a low fluidity and hinder the use of BHD in current diesel engines.…”