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

Modified waste egg shell derived bifunctional catalyst for biodiesel production from high FFA waste cooking oil: a review

Global energy crisis are as a result of gradual depletion of fossil fuel reserves, coupled with population growth in developing countries. Besides, fossil fuels are not environmentally benign as they are associated with problems, i.e. global warming, high toxicity and non biodegradability, hence it is considered as non sustainable source of energy. Without doubt, biofuel-based energy is a promising long-term energy source that can reduce the over dependence on fossil fuels as a result of feedstocks availability and renewability. However, biodiesel production from vegetable oil using the traditional homogeneous catalytic system is no longer defensible by industries in the near future, particularly due to food-fuel rivalry and ecological problems related to the conventional homogeneous catalytic system. This review presents a comprehensive step by step process of converting waste cooking oil (WCO) to biodiesel, using modified waste egg shell catalyst. The modified waste egg shell derived bi-functional catalyst could easily be removed from the fatty acid methyl esters (FAME) with limited environmental effects. The new modified catalytic system is able to convert the high free fatty acid (FFA) content waste cooking oil to FAME efficiently under moderate reaction conditions. Utilization of waste cooking oil as a feedstock for biodiesel production will reduce the food security issues that stem the biodiesel production from food-grade oil. Moreover, it will reduce the total production cost of the FAME due to its low cost. The major objective of this article is to demonstrate the current state of the use of heterogeneous bifunctional acid/base catalyst to produce biodiesel from green and non-edible waste cooking oil. At the end of the article, perspectives and future developments are also presented

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

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

Towards sustainable green diesel fuel production: Advancements and opportunities in acid-base catalyzed H2-free deoxygenation process

This review delves into the potential of renewable biomass for green diesel production. Deoxygenation technology offers a promising method for converting biomass-derived oxygenates oil into high-grade hydrocarbon factions. Hence, various deoxygenation pathways of biomass conversion under free‑hydrogen environment were explored. Additionally, the prospects of acid-base bifunctional catalysts to facilitate deoxygenation was discussed, highlighting the correlation between the physicochemical properties of the catalysts and catalytic activity. However, it should be noted that the acid-base characteristics of the catalysts contribute to the breaking of C–O bonds of oxygenated oil via undesirable pathways, which contributed to unfavorable by-product and catalyst deactivation

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)

Highly thermal stable catalyst for deoxygenation jatropha oil under free hydrogen and solvent for hydrocarbons like diesel fuel with highly thermal flow properties

Jatropha oil is an oil that obtained from a plant known as Jatropha Curcas. This oil is used as a feedstock due to readily available in nature and will be less expensive compared to another feedstock. In this study, green diesel was produced through deoxygenation of Jatropha oil catalysed by Co15%-La25% bimetallic with activated carbon supported. These activated carbons were obtained through the calcination of the death tree before synthesized it through phosphorylation by mixing it with phosphoric acid for 12 hours at 160 oC before dopping it with Lanthanum and Cobalt metal through wet impregnation method. The physicochemical properties of the prepared catalyst were characterized by using Fourier-transform infrared(FTIR) spectroscopy, X-ray diffraction(XRD), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), gas chromatography flame ionization detector(GC-FID) and gas chromatography mass spectrometry(GC-MS). The effect of catalyst loading, reaction time, and reaction temperature on deoxygenation of Jatropha oil were investigated. The thermal properties from TGA show that the catalyst was stable up to 500oC. The catalyst demonstrated a superior catalytic performance in deoxygenation reaction under optimal condition (5% catalyst loading, 3 hours and 350 oC), 80 % conversion of Jatropha oil to green diesel was achieved in 3 hours. Reusability test of the catalyst was examined and results showed that the synthesized catalyst could be reused up to 4 times with maintaining Jatropha oil conversion at above 50 %. In nutshell, the Co15%-La25% bimetallic with activated carbon support catalyst is recyclable, reusable and can be used to produced green diesel via deoxygenation of Jatropha oil

In-situ operando and ex-situ study on light hydrocarbon-like-diesel and catalyst deactivation kinetic and mechanism study during deoxygenation of sludge oil

Deoxygenation is a highly significant means of generating oxygen-free hydrocarbon fuels from liquid biomass. This study will deoxygenate sludge palm oil (FFA % = 42.35%) in an H2-free atmosphere through a series of Mn-Co supported AC catalysts (MnO0.5CoO0.5/AC, Mn0.5Co0.5S/AC and Mn0.5Co0.5P/AC). The XAS in-situ results confirm that the preparation method of formation the catalyst structure was successful. The catalytic results show that by oligomerizing unsaturated fatty acids produced during Diels-Alder reactions or radical additions, the MnO0.5)CoO0.5/AC can largely enhance the production of heavy products. It is a straightforward process to transform these heavy products into coke species, which enables the rapid deactivation of the catalyst. This study additionally showed that AC-supported sulphide and phosphide Mn-Co catalysts are hugely beneficial for steadily and reliably acquiring an above-average yield of diesel-range hydrocarbons at substantially reduced temperatures whilst simultaneously effectively impeding catalyst deactivation during deoxygenation. The deactivation kinetic study conform that the deactivation happens by the coke formation and flow the second order deactivation