The production of diesel-like fuel and base oil from bioderived fatty alcohol through a two-steps process, dehydration reaction and oligomerization reaction, was studied. The bioderived 1-decanol was converted to olefin mixtures and di-n-decyl ether via the dehydration over commercial γ-alumina catalysts with and without acid modification in a fixed-bed reactor at different temperatures. The catalysts studied were characterized using nitrogen adsorption, temperature-programmed desorption, X-ray diffraction, and thermogravimetric analysis. The dehydration reaction over the unmodified Al 2 O 3 was found to be dominant toward the selectivity for 1-decene. The modified Al 2 O 3 was shown to promote skeletal internal isomerization and cracking reaction due to strong acid sites. Furthermore, the stability testing results of 1.5 M (H 2 SO 4 )/Al 2 O 3 at 573 K demonstrated a rapid deactivation of strong acid sites during the first 10 h of operation. Oligomerization of mixed olefins (1decanol, 1-decene, and internal olefin) over USY zeolite was found to give the highest conversion of 60%, compared to other zeolites, and the selectivities for dimers, trimers, and heavier hydrocarbons were 72, 24, and 4%, respectively. Evaluation of oligomers properties such as viscosity, viscosity index, simulation distillation, and pour point indicated that dimers and heavier hydrocarbons after hydrogenation can be used as transportation fuel and biobased oil.

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A promising production route for a high-quality base stock for lubricants is the oligomerization of high molecular-weight olefins in a high energy efficiency system. Oligomerization of 1-decene (C10) was conducted in a microwave-assisted system over a HY zeolite catalyst at different reaction temperatures and times. Higher reaction temperature resulted in increasing formation of dimers and trimers. The oligomerization reaction yielded 80% conversion, 54.2% dimer product, 22.3% trimer product and 3.4% heavier product at 483 K for a reaction time of 3 h. The best fit kinetic model for the dimerization reaction was formulated from an assumption of no vacant reaction sites. For the trimerization reaction, a molecule of dimer (C20) formed on the active site, interacted with a molecule of 1-decene in the bulk solution to form a molecule of trimer (C30). Apparent activation energies for the dimerization and trimerization reactions were 70.8 ± 0.8 and 83.6 ± 0.9 kJ/mol, respectively. The C13-NMR spectrum indicated that the oligomer product contained a significant portion of highly branched hydrocarbons, causing a substantial reduction in the viscosity index compared to conventional poly-alpha olefin lubricant (PAO).

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In this paper, the ride performance of a vehicle with active suspension and Linear Quadratic Gaussian (LQG) controller has been studied and is compared to the performances of a traditional passive suspension system. The study includes variables that are related to a passenger’s comfort: vertical position, vertical velocity, pitch angle, pitch velocity, roll angle, and roll velocity. The performances of the two systems are evaluated by maximum values and root mean square (RMS) of the variables when riding on a sinusoidal road profile. The simulation results show that the vehicle with active suspension and LQG controller performs better than passive suspension system where the maximum values decrease by 85.77%, 92.73%, 50.31% 86.83%, 89.41%, 43.28%, and RMS values decrease by 88.59%, 92.36%, 42.99%, 87.61%, 90.85%, and 42.79% for vertical position, vertical velocity, pitch angle, pitch velocity, roll angle, and roll velocity, respectively.

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