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

Pyrolytic-deoxygenation of triglycerides model compound and non-edibleoil to hydrocarbons over SiO₂-Al2O₃ supported NiO-CaO catalysts

Catalytic deoxygenation (DO) of triglycerides-based feeds to diesel-like fuel was investigated over NiO-CaO/SiO₂-Al2O₃ and NiO/SiO₂-Al2O₃ catalysts using semi-batch reactor under partial vacuum and inert N₂ flow. The results showed that the bi-functional catalyst exhibited the highest DO activity with product selectivity toward diesel-like fuel n-(C₁₃–C₂₀). The catalytic process appeared to inhibit the occurrence of side reactions via neutralization of the strong acid sites. On the other hand, DO reaction under inert N₂ flow has improved the deoxygenated product, which demonstrate that N₂ flow condition has effectively removed the decarboxylation/decarbonylation gasses (CO₂/CO) from poisoning the catalyst active sites. The high concentration of strong basic-acid sites of the catalyst is the main reason for increased CC cleavage pathway, while milder acidic sites responsible for CO cleavage pathway. High degree of unsaturated fatty acid in the feedstock has affected adversely the DO of triglycerides by accelerating the catalyst deactivation. The N₂ flow condition, degree of unsaturated fatty acid in the feedstocks, acidity and basicity of the catalysts are important factors to improve DO activity as well as product selectivity

Pyrolytic–deoxygenation of triglyceride via natural waste shell derived Ca(OH)2 nanocatalyst

Cracking–Deoxygenation process is one of the important reaction pathways for the production of biofuel with desirable n-C17 hydrocarbon chain via removal of oxygen compounds. Calcium-based catalyst has attracted much attention in deoxygenation process due its relatively high capacity in removing oxygenated compounds in the form of CO2 and CO under decarboxylation and decarbonylation reaction, respectively. In the present study, deoxygenation of triolein was investigated using Ca(OH)2 nanocatalyst derived from low cost natural waste shells. The Ca(OH)2 nanocatalyst was prepared via integration techniques between surfactant treatment (anionic and non-ionic) and wet sonochemical effect. Results showed that sonochemically assisted surfactant treatment has successfully enhanced the physicochemical properties of Ca(OH)2 nanocatalyst in terms of nano-particle sizes (∼50 nm), high surface area (∼130 m2 g−1), large porosity (∼18.6 nm) and strong basic strength. The presence of superior properties from surfactant treated Ca(OH)2 nanocatalysts rendered high deoxygenation degree, which are capable of producing high alkane and alkene selectivity in chain length of n-C17 (high value of C17/(n-C17 + n-C18) ratio = 0.88). Furthermore, both Ca(OH)2–EG and Ca(OH)2–CTAB nanocatalysts showed high reactivity with 47.37% and 44.50%, respectively in total liquid hydrocarbon content of triolein conversion with high H/C and low O/C ratio

Catalytic hydrothermal liquefaction of empty fruit bunch in subcritical water over bimetallic modified zeolite

Catalytic hydrothermal liquefaction of empty fruit bunch (EFB) with no added H2 effectively produces biomass derived fuel or known as bio-oil. In this study, a bimetallic modified zeolite (BaNi, BaLa and BaCe/CHZSM5) catalyst with a series of dosage ratio (1:1, 1:2 and 2:1) was used for the EFB conversion to bio-oil. Ni, La and Ce addition to the Ba/CHZSM5 showed significant changes on the physicochemical properties of catalysts and exhibited enhanced catalytic performance. The activity-structure correlation revealed that EFB conversion and bio-oil yield were favoured on bimetallic modified CHZSM5 and the most effective catalyst was Ba1La2/CHZSM5. Brunauer–Emmett–Teller (BET) surface area measurement and temperature programmed desorption of ammonia (TPD-NH3) results confirmed that high surface area and rich acidic sites of Ba1La2/CHZSM5 catalyst eventually enhanced the catalytic activity in HTL of EFB. Comparing to other bimetallic modified catalyst, the desirable aromatic and aliphatic hydrocarbon also predominated over Ba1La2/CHZSM5 catalysed reaction which demonstrated that this catalyst have a good ability in produce high quality of bio-oil with less oxygenated compounds

Efficient reaction for biodiesel manufacturing using bi-functional oxide catalyst

The search for biofuel in order to complement the future shortage of fuels and mitigate the poisonous air and water pollution has become so considerate in the last few decades. The choice of feedstock and catalyst system for biofuel production has been very difficult considering many drawbacks from food-fuel competition to catalyst separation and water washing after the reaction. To address these issues, acid-base bi-functional catalysts and waste based vegetable oil were considered for the sustainable production of biofuels. Bifunctional catalyst has the capacity to successfully transform waste based vegetable oil into useful biofuel under mild reaction pa rameters. In this work, a newly developed bimetallic tungsten- zirconia (W–Zr) modified waste shell catalyst samples were employed for the simultaneous esterification and transesterification of unrefined palm-derived waste oil (PDWO) to biodiesel in one-pot reaction. These catalysts were successfully synthesized using simple wet impregnation technique and characterized by SEM, BET, XRD, and TPD characterization techniques. The catalyst was able to achieved the maximum biodiesel yield of 94.1% in 1 h under optimized reaction parameters

Production of green diesel via hydrogen-free and solventless deoxygenation reaction of waste cooking oil

This work was successfully produced green diesel from domestic waste cooking oil via hydrogen-free and solventless deoxygenation over nickel-cobalt/organosilane-SBA-15 catalyst. Highly effective mesostructured catalyst has been synthesized by functionalizing with selected loadings of 3-Mercaptopropyl (trimethoxysilane) (MPTMS) onto SBA-15 by co-condensation method, followed by nickel and cobalt impregnation to produce 5Ni5Co/SBA-15-SH 0.1, 5Ni5Co/SBA-15-SH 0.3 and 5Ni5Co/SBA-15-SH 0.5. The 5Ni5Co/SBA-15-SH 0.1 catalyst exhibits high surface area and pore size (509 m2/g, 4.6 nm), which proved that the addition of MPTMS had increased the surface area and pore size due to the interaction between MPTMS and TEOS. The acidity of the synthesized catalyst also remarkably increased after MPTMS functionalization, suggesting the presence of the sulfonic acid group derived from the oxidation of MPTMS has enhanced the acidity of the catalyst. The amount of nickel and cobalt successfully impregnated onto the catalysts also show increment (5%–9%) following the amount of MPTMS added, which attributed to a strong interaction between metal species and support surface result in a homogeneous distribution of nickel and cobalt as observed in HRTEM. The MPTMS functionalization has successfully enlarged the surface area and increased the catalyst's acidic properties, enhancing the catalyst's deoxygenation activity. The catalytic activity study via deoxygenation was performed in a solventless and hydrogen-free reaction system to produce green diesel (350 °C within 2 h using 5%wt. Catalyst loading). Based on GC-FID analysis, it was proven that 5Ni5Co/SBA-15-SH 0.1 exhibits high hydrocarbon yield (77%) and diesel selectivity (70%) with the reusable catalyst for 4 catalytic cycles by maintaining the catalyst's selectivity. Hence, this work can produce green diesel from low-cost waste cooking oil via the synthesized organosilane-functionalized catalyst

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

Production of biodiesel from waste cooking oil via deoxygenation using ni-mo/ac catalyst

Waste cooking oil (WCO) from palm oil is one of the most prospective biodiesel feedstock when compared to other oil seeds. Thus, WCO has great potential as a green source of diesel fuel for engines in motor vehicles and machinery. This project aimed to study the potential of three randomly selected types of WCO, namely; sample A (used 1× once to fry an egg), sample B (used 3 – 5× to fry salted fish), and sample C (used repeatedly to fry banana fritter) for the production of green diesel fuel over Ni-Mo/AC (nickel and molybdenum oxides incorporated with activated carbon) catalyst through the deoxygenation (DO) process. The prepared catalyst was characterized through X-ray diffraction (XRD), thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM). The DO process was performed at 350 ◦C to remove oxygen from the WCO samples. The liquid products were analysed by gas chromatography-mass spectrometer (GC-MS) and gas chromatography-flame ionization detector (GC-FID), to measure the yields of straight-chain hydrocarbons and fractions in the range C8 - C20. Results showed that the highest n-(C8 - C20) hydrocarbon fractions were produced in the order of sample B (89.93%) > C (88.84%) > A (82.81%)

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