scholarly journals Technological Aspects of Vegetable Oils Transesterification with Ethanol in the Presence of Metal Oxides

2020 ◽  
Vol 69 (7-8) ◽  
pp. 365-370
Author(s):  
Yuriy Melnyk ◽  
Roman Starchevskyi ◽  
Stepan Melnyk
Keyword(s):  
Zinc Oxide ◽  
Catalytic Activity ◽  
Metal Oxide ◽  
Metal Oxides ◽  
Vegetable Oil ◽  
Vegetable Oils ◽  
Sunflower Oil ◽  
Mass Fraction ◽  
Oxide Catalyst ◽  
Oxide Particles

Transesterification of vegetable oil with ethanol in the presence of fine metal oxide particles as catalysts has been investigated. Zinc and nickel(II) oxides were shown to have the highest catalytic activity. In their presence, the conversion of sunflower oil triglycerides, after 150 min, reached 95.3 and 94.2 %, respectively. The optimal mass fraction of zinc oxide catalyst was found to be 0.25–0.31 %. In the presence of zinc oxide, with mass fraction of water in ethanol of 5 and 10 %, the conversion of triglycerides was 98.5 and 94.8 %, respectively.

LOCATION OF OILSEED PRODUCTION IN TERMS OF VEGETABLE OIL EXPORT

2020 ◽  
Vol 1 (10) ◽  
pp. 94-100
Author(s):  
Yu. V. RAGULINA ◽  
Keyword(s):  
Seed Production ◽  
Vegetable Oil ◽  
Vegetable Oils ◽  
Sunflower Oil ◽  
World Export ◽  
Oil Export ◽  
Oilseed Production

The article is devoted to the issues of placing seed production in the conditions of world export of vegetable oils. In 2019, the volume of Russian exports of sunflower oil exceeded 3 million tons for a total of $ 2,2 billion, which is about 30% of the vegetable oil produced in the country. In Russia, the main oilseeds are sunflower, rapeseed, and soy. Less common crops include oilseed flax, ginger, mustard, and safflower. It is stated that in 2001–2019, the acreage of all types of oilseeds in the country increased by more than 2 times, and the gross harvest – by 3,3 times, while the yield increased by 1,4 times.

scholarly journals THE USE OF NANOSCALE ZINC OXIDE IN WOOD-BASED COMPOSITIONS

2021 ◽  
Author(s):  
S. Neminushchaya ◽  
E. Tomina ◽  
A. Dmitrenkov
Keyword(s):  
Zinc Oxide ◽  
Vegetable Oil ◽  
Zinc Oxide Nanoparticles ◽  
Sol Gel ◽  
Environmental Safety ◽  
Oxide Nanoparticles ◽  
Natural Wood ◽  
Oxide Particles ◽  
Used Vegetable Oil ◽  
20 Nm

The aim of this work was to study compositions based on vegetable oil waste and nanoscale zinc oxide particles for processing natural wood. The sol-gel method was used for the synthesis of zinc oxide nanoparticles. The synthesized zinc oxide nanoparticles did not contain impurities and had a shape close to spherical, and their size did not exceed 20 nm. We used freshly prepared suspensions of zinc oxide nanoparticles in used vegetable oil with their content in the amount of 0.1, 0.5 and 1.0 wt. parts per 100 parts of oil. The wood was treated by hot-cold impregnation. The tests were carried out on samples of birch and pine wood of standard sizes. In the modified samples, the wetting angle, moisture and water absorption, as well as their swelling were determined. It is shown that the use of zinc oxide nanoparticles in compositions based on vegetable oil waste can significantly reduce the moisture and water resistance of wood and reduce its swelling. The optimal dosages of the nanopowder introduced into the used vegetable oil and the conditions of impregnation were selected. The compositions used on the basis of vegetable oil waste are characterized by environmental safety, and the resulting wood samples had an improved appearance.

scholarly journals CO Oxidation over Metal Oxide (La2O3, Fe2O3, PrO2, Sm2O3, and MnO2) Doped CuO-Based Catalysts Supported on Mesoporous Ce0.8Zr0.2O2 with Intensified Low-Temperature Activity

Catalysts ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 724 ◽  
Author(s):  
Yan Cui ◽  
Leilei Xu ◽  
Mindong Chen ◽  
Chufei Lv ◽  
Xinbo Lian ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Low Temperature ◽  
Metal Oxide ◽  
Metal Oxides ◽  
Co Oxidation ◽  
Active Sites ◽  
Earth Metal ◽  
High Dispersion ◽  
Impregnation Method ◽  
X Ray

CuO-based catalysts are usually used for CO oxidation owing to their low cost and excellent catalytic activities. In this study, a series of metal oxide (La2O3, Fe2O3, PrO2, Sm2O3, and MnO2)-doped CuO-based catalysts with mesoporous Ce0.8Zr0.2O2 support were simply prepared by the incipient impregnation method and used directly as catalysts for CO catalytic oxidation. These mesoporous catalysts were systematically characterized by X-ray powder diffraction (XRD), N2 physisorption, transmission electron microscopy (TEM), energy-dispersed spectroscopy (EDS) mapping, X-ray photoelectron spectroscopy (XPS), and H2 temperature programmed reduction (H2-TPR). It was found that the CuO and the dopants were highly dispersed among the mesoporous framework via the incipient impregnation method, and the strong metal framework interaction had been formed. The effects of the types of the dopants and the loading amounts of the dopants on the low-temperature catalytic performances were carefully studied. It was concluded that doped transition metal oxides could regulate the oxygen mobility and reduction ability of catalysts, further improving the catalytic activity. It was also found that the high dispersion of rare earth metal oxides (PrO2, Sm2O3) was able to prevent the thermal sintering and aggregation of CuO-based catalysts during the process of calcination. In addition, their presence also evidently improved the reducibility and significantly reduced the particle size of the CuO active sites for CO oxidation. The results demonstrated that the 15CuO-3Fe2O3/M-Ce80Zr20 catalyst with 3 wt. % of Fe2O3 showed the best low-temperature catalytic activity toward CO oxidation. Overall, the present Fe2O3-doped CuO-based catalysts with mesoporous nanocrystalline Ce0.8Zr0.2O2 solid solution as support were considered a promising series of catalysts for low-temperature CO oxidation.

Coating of uniform inorganic particles with polymers: III. Polypyrrole on different metal oxides

1995 ◽  
Vol 10 (5) ◽  
pp. 1327-1336 ◽  
Author(s):  
Chin-Lin Huang ◽  
Egon Matijevic
Keyword(s):  
Metal Oxide ◽  
Metal Ions ◽  
Metal Oxides ◽  
Dissolution Process ◽  
Reductive Dissolution ◽  
Inorganic Particles ◽  
Ethanol Medium ◽  
Oxide Particles ◽  
Coated Spheres

Five kinds of uniform metal oxide particles (α-Fe2O3, CeO2, CuO, NiO, and SiO2) were coated with polypyrrole by reacting the dispersed solids with pyrrole in a water/ethanol medium without the use of a soluble oxidant. When the process was carried out in air, all particles were coated with the polymer, although the thickness of the layer varied on different cores. In CuO dispersions, independent polypyrrole particles were produced in addition to coated spheres. While oxygen is the major oxidant that initiates the polymerization of pyrrole, some metal oxides may also affect the reaction both in terms of the amount and the composition of the shell. Thus, α-Fe2O3 and SiO2 were found to be inactive in the polymerization, while CeCh and CuO react with the adsorbed pyrrole molecules through a reductive-dissolution process, in which the monomers are oxidized, causing a release of reduced metal ions.

scholarly journals Hydrothermal Liquefaction of Microalga Using Metal Oxide Catalyst

Processes ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 15 ◽  
Author(s):  
Alejandra Sánchez-Bayo ◽  
Rosalía Rodríguez ◽  
Victoria Morales ◽  
Nima Nasirian ◽  
Luis Fernando Bautista ◽  
...  
Keyword(s):  
Metal Oxide ◽  
Metal Oxides ◽  
Energy Recovery ◽  
Heterogeneous Catalysts ◽  
Oxide Catalyst ◽  
Thermal Reaction ◽  
Hydrothermal Liquefaction ◽  
Heating Value ◽  
Metal Oxide Catalyst ◽  
Autoclave Reactor

The yield and composition of the biocrude obtained by hydrothermal liquefaction (HTL) of Nannocloropsis gaditana using heterogeneous catalysts were evaluated. The catalysts were based on metal oxides (CaO, CeO2, La2O3, MnO2, and Al2O3). The reactions were performed in a batch autoclave reactor at 320 °C for 10 min with a 1:10 (wt/wt) microalga:water ratio. These catalysts increased the yield of the liquefaction phase (from 94.14 ± 0.30 wt% for La2O3 to 99.49 ± 0.11 wt% for MnO2) as compared with the thermal reaction (92.60 ± 1.20 wt%). Consequently, the biocrude yields also raised in the metal oxides catalysed HTL, showing values remarkably higher for the CaO (49.73 ± 0.9 wt%) in comparison to the HTL without catalyst (42.60 ± 0.70 wt%). The N and O content of the biocrude obtained from non-catalytic HTL were 6.11 ± 0.02 wt% and 10.50 ± 0.50 wt%, respectively. In this sense, the use of the metal oxides decreased the N content of the biocrude (4.62 ± 0.15–5.45 ± 0.11 wt%), although, they kept constant or increased its O content (11.39 ± 2.06–21.68 ± 0.03 wt%). This study shows that CaO, CeO2 and Al2O3 can be promising catalysts based on the remarkable amount of biocrude, the highest values of C, H, heating value, energy recovery, and the lowest content of N, O and S.

scholarly journals A Moving Bed Reactor for Thermochemical Energy Storage Based on Metal Oxides

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1232 ◽  
Author(s):  
Nicole Carina Preisner ◽  
Marc Linder
Keyword(s):  
High Temperature ◽  
Energy Storage ◽  
Iron Oxide ◽  
Metal Oxide ◽  
Metal Oxides ◽  
Thermal Energy ◽  
High Energy ◽  
Heat Extraction ◽  
Moving Bed ◽  
Oxide Particles

High-temperature thermal energy storage enables concentrated solar power plants to provide base load. Thermochemical energy storage is based on reversible gas–solid reactions and brings along the advantage of potential loss-free energy storage in the form of separated reaction products and possible high energy densities. The redox reaction of metal oxides is able to store thermal energy at elevated temperatures with air providing the gaseous reaction partner. However, due to the high temperature level, it is crucial to extract both the inherent sensible and thermochemical energies of the metal-oxide particles for enhanced system efficiency. So far, experimental research in the field of thermochemical energy storage focused mainly on solar receivers for continuously charging metal oxides. A continuously operated system of energy storage and solar tower decouples the storage capacity from generated power with metal-oxide particles applied as heat transfer medium and energy storage material. Hence, a heat exchanger based on a countercurrent moving bed concept was developed in a kW -scale. The reactor addresses the combined utilization of the reaction enthalpy of the oxidation and the extraction of thermal energy of a manganese–iron-oxide particle flow. A stationary temperature profile of the bulk was achieved with two distinct temperature sections. The oxidation induced a nearly isothermal section with an overall stable off-gas temperature. The oxidation and heat extraction from the manganese–iron oxide resulted in a total energy density of 569 kJ/kg with a thermochemical share of 21.1%.

Metal Oxide Particles: Multi Ball-In-Ball Hybrid Metal Oxides (Adv. Mater. 15/2011)

2011 ◽  
Vol 23 (15) ◽  
pp. 1687-1687 ◽  
Author(s):  
Won Cho ◽  
Yun Hee Lee ◽  
Hee Jung Lee ◽  
Moonhyun Oh
Keyword(s):  
Metal Oxide ◽  
Metal Oxides ◽  
Oxide Particles

scholarly journals Eco-Friendly Production of AuNPs and Their Impact on the Oil Oxidative Stability

Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1668
Author(s):  
Flávio S. Michels ◽  
Pablo J. Gonçalves ◽  
Valter A. Nascimento ◽  
Samuel L. Oliveira ◽  
Heberton Wender ◽  
...  
Keyword(s):  
Oxidative Stability ◽  
Vegetable Oil ◽  
Vegetable Oils ◽  
Sunflower Oil ◽  
Inductively Coupled Plasma ◽  
Deposition Time ◽  
Optical Emission ◽  
Oil Well ◽  
Sputtering Deposition ◽  
Inductively Coupled

Vegetable oils have been used for different applications and, more recently, as an active host medium to obtain nanoparticles for employment in bionanotechnological applications. Nevertheless, oils are very susceptible to oxidation during production, storage, and transportation because of their chemical composition. Consequently, any modification in their production must be accompanied by an analysis of the oxidative stability. In this study, naked and biocompatible gold nanoparticles (AuNPs) were grown on sunflower oil during sputtering deposition using different deposition times. Size and morphology were determined by transmission electron microscopy (TEM) and their concentrations were found by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Rancimat® method was employed to evaluate the AuNPs influence on the oxidative stability of the vegetable oil. Well-dispersed quasi-spherical NPs were produced with a mean diameter in the 2.9–3.7 nm range and they were concentration-dependent on the deposition time. A concentration of about 11 mg/L, 38 mg/L, and 225 mg/L of AuNPs was obtained for a deposition time of 5 min, 15 min, and 30 min, respectively. The results also revealed that AuNPs negatively affected the oxidative stability of the sunflower oil and exponentially reduced the induction period (IP) with the increase in AuNPs content. IP reductions of 63%, 77%, and 81% were determined for the AuNPs containing samples at 11 mg/L, 38 mg/L, and 225 mg/L. For the first time, it is reported that naked AuNPs promote the rapid degradation of vegetable oil and this points out the need for attention relative to the quality of vegetable oils used to host metal nanoparticles.

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