Effective catalytic deoxygenation of waste cooking oil over nanorods activated carbon supported CaO

Under nitrogen atmosphere, waste cooking oil (WCO) was deoxygenated in semi-batch experiments by using the nanorods of phosphate-activated carbon, which is derived from walnut shell and promoted by CaO as catalyst at 350 °C. The deoxygenation reaction showed high activity (> 48% hydrocarbon yield) and high selectivity towards decarboxylation/decarbonylation (deCOx) reactions via exclusive formation of green diesel C15 fraction (> 60%). The high activity and high selectivity were attributed to the good physicochemical characteristics of the catalyst, including improved metal dispersion, high surface area and high basic properties. Overall, this study demonstrates CaO/AC catalytic deoxygenation as a promising approach to produce liquid green diesel C15 from WCO under hydrogen-free atmosphere

Nanomaterials: An Overview of Nanorods Synthesis and Optimization

Nanorods are nanostructures that are the object of fundamental and applied research. They may be prepared from carbon, gold, zinc oxide, and many other materials. They are bigger than individual atoms (measured in angstroms, 1 Å = 10−10 m) and also than small molecules. The turning point for nanomaterials research was the discovery of carbon nanotubes in 1991. Their mechanical, electrical, and optical properties depend upon their size, allowing for multiple applications. Also, nanorods may be functionalized for different applications. In this Chapter, the methods of synthesis and analysis, and the applications of carbon, zinc oxide, gold, and magnetic nanorods are reviewed

Sulfonated functionalization of carbon derived corncob residue via hydrothermal synthesis route for esterification of palm fatty acid distillate

Low-cost biodiesel was successfully produced through esterification of the high-free fatty acid (FFA) feedstock of palm fatty acid distillate over corncob residue-derived heterogeneous solid acid catalyst. Sulfonated functionalized carbon derived from corncob was synthesized via hydrothermal carbonization followed by chemical activation using concentrated H2SO4. The hydrothermal carbonization technique allows efficient carbonization because it is able to maintain active polar species in the corncob. H2SO4 activation can effectively improve the acid strength of HTC-S catalyst. The HTC-S catalyst was optimized via the OVAT technique, and 92% FFA with a FAME yield of 85% was achieved at optimum conditions of 2 h reaction time, 70 °C reaction temperature, 3wt.% catalyst loading, and 15:1 methanol-to-oil molar ratio. Regeneration of the reused HTC-S catalyst via H2SO4 treatment was an effective technique to maintain catalyst stability

Characterization and application of aluminum dross as catalyst in pyrolysis of waste cooking oil

Aluminium dross, a waste material produced by dissolution of aluminum scrap, was characterized physically and chemically by various analysis techniques for a potential to be used as catalyst. Using catalyst from waste materials reduced the cost for synthesizing of new catalyst. An efficient catalyst derived from industrial solid waste was modified by acid washing for using in a pyrolysis of waste cooking oil. The modification of aluminum dross resulted in increased surface area (from 0.96 to 68.24 m2/g), acidity (from 315 to 748 µmol/g) and thermal stability. Pyrolysis waste cooking oil was used to test the performance of aluminum dross as catalyst before and after modification. The product analysis showed a better result than the unmodified material based on increased yield of bio-oil and improved selectivity

Free-H2 deoxygenation of Jatropha curcas oil into cleaner diesel-grade biofuel over coconut residue-derived activated carbon catalyst

Diesel-like hydrocarbons were produced by the catalytic deoxygenation (DO) of Jatropha curcas oil (JCO) over novel Agx/AC and Niy-Agx/AC catalysts under an H2-free atmosphere. The AC was synthesized from coconut fibre residues (CFR), where CFR is the by-product from coconut milk extraction and is particularly rich in soft fibres with high mineral content. The Niy-Agx/AC catalyst afforded higher DO activity via the decarboxylation/decarbonylation (deCOx) route than Agx/AC due to the properties of Ni, synergistic interaction of Ni and Ag species, adequate amount of strong acid sites and large number of weak acid sites, which cause extensive C-O cleavage and lead to rich formation of n-(C15+C17) hydrocarbons. The effect of Ag and Ni content were studied within the 5 to 15 wt% range. An optimum Ni and Ag metal content (5 wt%) for deCOx reaction was observed. Excess Ni is not preferable due to a tendency for cracking and Ag-rich containing catalyst weakly enforced triglycerides breaking. The Ni5-Ag5/AC govern exclusively decarbonylation reaction, which corroborates the presence of Ni²⁺ species and a high amount of strong acid sites. Ultimately, Ni5-Ag5/AC in the present study shows excellent chemical stability with consistent five reusability without drastic reduction of hydrocarbon yield (78–95%) and n-(C15+C17) selectivity (82–83%), which indicate favourable application in JCO DO

Effect of bimetallic Co-Cu/Dolomite catalyst on glycerol conversion to 1,2-propanediol

This present study examines the efficacy of using dolomite (Dol, CaMg(CO3)2)-supported copper (Cu) and cobalt (Co) bimetallic and monometallic catalysts for the hydrogenolysis of glycerol to propylene glycol (PG; 1,2-PDO). The proposed catalysts were generated using the impregnation process before they were calcined at 500°C and reduced at 600°C. Advanced analytical techniques namely Brunauer, Emmett, and Teller (BET) method; the Barrett, Joyner, and Halenda (BJH) method; temperature-programmed desorption of ammonia (NH3–TPD), hydrogen-temperature programmed reduction (H2-TPR), X-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM) were then used to characterise the synthesised catalysts, whose performance was then tested in the hydrogenolysis of glycerol. Of all the synthesised catalysts tested in the hydrogenolysis process, the Co-Cu/Dol bimetallic catalyst performed best, with an 80.3% glycerol conversion and 85.9% PG selectivity at a pressure of 4 MPa, a temperature of 200°C, and a reaction time of 10 hours. Its high catalytic performance was attributed to effective interactions between its Co-Cu-Dol species, which resulted in acceptable acidity, good reducibility of metal oxide species at low temperatures, larger surface area (15.3 m2 g-1), large-sized particles, fewer pores (0.032 cm3 g-1), and smaller pore diameter (0.615 nm)

Production of green diesel from catalytic deoxygenation of chicken fat oil over a series binary metal oxide-supported MWCNTs

Deoxygenation processes that exploit milder reaction conditions under H2-free atmospheres appear environmentally and economically effective for the production of green diesel. Herein, green diesel was produced by catalytic deoxygenation of chicken fat oil (CFO) over oxides of binary metal pairs (Ni–Mg, Ni–Mn, Ni–Cu, Ni–Ce) supported on multi-walled carbon nanotubes (MWCNTs). The presence of Mg and Mn with Ni afforded greater deoxygenation activity, with hydrocarbon yields of >75% and n-(C15 + C17) selectivity of >81%, indicating that decarboxylation/decarbonylation (deCOx) of CFO is favoured by the existence of high amount of lower strength strong acidic sites along with noticeable strongly basic sites. Based on a series of studies of different Mg and Mn dosages (5–20 wt%), the oxygen free-rich diesel-range hydrocarbons produced efficiently by Ni10–Mg15/MWCNT and Ni10–Mn5/MWCNT catalysts yielded >84% of hydrocarbons, with n-(C15 + C17) selectivity of >85%. The heating value of the green diesel obtained complied with the ultra-low sulphur diesel standard

Biofuel and Biorefinery Technologies

The global demand for energy is expected to rise up to 59% by the year 2035. This is due to the increasing technology developments and contemporary industrialization. Continues trends of these simultaneously will affects the crude fossil oil reserves progressively. Therefore, biofuels that are predominantly produced from the biomass based feedstocks such as plant, algae material and animal waste. Liquid or gaseous biofuels are the most simple to ship, deliver, and burn since they are easier to transport, deliver, and burn cleanly. The key contributor to the elevated green house gaseous concentration is carbon dioxide (CO2). Two-thirds of global anthropogenic CO2 emissions are due to fossil fuel combustion, with the remaining third attributed to land-use changes. Interestingly, recent literature has announced that the utilization of liquid biofuels capable of reducing the CO and CO2 emissions. Other positive impacts of the liquid biofuels are; (1) reduce the external energy dependence, (2) promote the regional engineering, (3) increase the Research & Development activities, (4) reduce the environmental effects of electricity generation and transformation, (5) improve the quality of services for rural residents and (6) provide job opportunities

Selective deoxygenation of sludge palm oil into diesel range fuel over Mn-Mo supported on activated carbon catalyst

Originating from deoxygenation (DO) technology, green diesel was innovated in order to act as a substitute for biodiesel, which contains unstable fatty acid alkyl ester owing to the existence of oxygenated species. Green diesel was manufactured following a process of catalytic DO of sludge palm oil (SPO). An engineered Mn(0.5%)-Mo(0.5%)/AC catalyst was employed in a hydrogen-free atmosphere. The influence of Manganese (Mn) species (0.1–1 wt.%) on DO reactivity and the dissemination of the product were examined. The Mn(0.5%)-Mo(0.5%)/AC formulation gave rise to a superior harvest of approximately 89% liquid hydrocarbons; a higher proportion of diesel fraction selectivity n-(C15 +C17) was obtained in the region of 93%. Where acid and basic active sites were present on the Mn(0.5%)-Mo(0.5%)/AC catalyst, decarboxylation and decarbonylation reaction mechanisms of SPO to DO were enhanced. Evidence of the high degree of stability of the Mn(0.5%)-Mo(0.5%)/AC catalyst during five continuous runs was presented, which, in mild reaction conditions, gave rise to a consistent hydrocarbon harvest of >72% and >94% selectivity for n-(C15 +C17)