The Roles of the Structure and Basic Sites of Sodium Titanates on Transesterification Reactions to Obtain Biodiesel

Sodium titanates were evaluated as heterogeneous catalysts for biodiesel production. Materials were prepared using an experimental design considering NaOH and TiO2 concentrations and hydrothermal and calcination temperatures as input variables. Materials characterization was carried out by DRX-Rietveld refinement, CO2-TPD, and XPS. Statistical analysis of the experimental results indicates that the calcination temperature is the most influential factor in the formation of sodium titanates with high catalytic performance in transesterification reactions. Further analysis of the oil-to-biodiesel conversion revealed that the catalytic activity of sodium titanates is directly correlated to the catalyst associated species and to the density of medium-strong basic sites on the surface of the material, obtaining up to 95% conversion to biodiesel at 60 °C using 3.6% weight catalyst with respect to oil.

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Biodiesel Production over Niobium-Containing Catalysts: A Review

Energies ◽

10.3390/en14175506 ◽

2021 ◽

Vol 14 (17) ◽

pp. 5506

Author(s):

Daniel Carreira Batalha ◽

Márcio José da Silva

Keyword(s):

Catalytic Activity ◽

Active Sites ◽

Heterogeneous Catalysts ◽

Raw Materials ◽

Catalytic Performance ◽

High Specific Surface Area ◽

Biodiesel Production ◽

Molar Ratio ◽

Main Reaction ◽

High Catalytic Activity

Nowadays, the synthesis of biofuels from renewable raw materials is very popular. Among the various challenges involved in improving these processes, environmentally benign catalysts compatible with an inexpensive feedstock have become more important. Herein, we report the recent advances achieved in the development of Niobium-containing heterogeneous catalysts as well as their use in routes to produce biodiesel. The efficiency of different Niobium catalysts in esterification and transesterification reactions of lipids and oleaginous raw materials was evaluated, considering the effect of main reaction parameters such as temperature, time, catalyst load, and oil:alcohol molar ratio on the biodiesel yield. The catalytic performance of Niobium compounds was discussed considering the characterization data obtained by different techniques, including NH3-TPD, BET, and Pyr-FT-IR analysis. The high catalytic activity is attributed to its inherent properties, such as the active sites distribution over a high specific surface area, strength of acidity, nature, amount of acidic sites, and inherent mesoporosity. On top of this, recycling experiments have proven that most Niobium catalysts are stable and can be repeatedly used with consistent catalytic activity.

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Effect of Fe Additives on the Catalytic Performance of Ion-Exchanged CsX Zeolites for Side-Chain Alkylation of Toluene with Methanol

Catalysts ◽

10.3390/catal9100829 ◽

2019 ◽

Vol 9 (10) ◽

pp. 829 ◽

Cited By ~ 4

Author(s):

Zhang ◽

Yuan ◽

Miao ◽

Li ◽

Shan ◽

...

Keyword(s):

Catalytic Activity ◽

Catalytic Performance ◽

High Yield ◽

Side Chain ◽

Impregnation Method ◽

Basic Sites ◽

Lewis Acidic Sites ◽

X Zeolite ◽

Acidic Sites ◽

Negative Effect

The side-chain alkylation of toluene with methanol was investigated over some Fe-modified Cs ion-exchanged X zeolite (CsX) catalysts prepared via the impregnation method using different iron sources. The absorption/activation behaviors of the reactants on the surface of the catalysts were studied by in situ Fourier-transform infrared (FT-IR) spectroscopy and temperature programmed desorption (TPD) mass measurements. Modification of CsX with a small amount of FeCl3 could result in a considerable decrease in catalytic activity, due mainly to the remarkable decrease in the density of acidic and basic sites of the catalysts. Interestingly, the Fe(NO3)3-modified CsX with an optimum Fe loading of 0.15 wt.% shows improved catalytic activity and high yield compared to the side-chain alkylation products. Modification of CsX with Fe(NO3)3 could also result in a decrease in basic sites of the catalyst. However, such a change does not bring an obvious negative effect on the adsorption/activation of toluene, while it could effectively inhibit the generation of the undesired bidentate formate. Furthermore, the introduced FeOx species (derived from the decomposition of Fe(NO3)3) may also act as new Lewis acidic sites to participate in the activation of methanol and to stabilize the formed active intermediates (i.e., unidentate formate). Therefore, modification of CsX with a suitable amount of Fe(NO3)3 may adjust its adsorption/activation ability for reagents by changing the acid–base properties of the catalyst, which can finally enhance the catalytic performance for the side-chain alkylation of toluene with methanol.

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A sustainable process for biodiesel production using Zn/Mg oxidic species as active, selective and reusable heterogeneous catalysts

Bioresources and Bioprocessing ◽

10.1186/s40643-019-0291-3 ◽

2020 ◽

Vol 7 (1) ◽

Cited By ~ 5

Author(s):

Marisa B. Navas ◽

José F. Ruggera ◽

Ileana D. Lick ◽

Mónica L. Casella

Keyword(s):

Castor Oil ◽

Heterogeneous Catalysts ◽

Catalytic Performance ◽

High Specific Surface Area ◽

Raw Material ◽

Biodiesel Production ◽

X Ray ◽

Renewable Biomass ◽

Butyl Esters ◽

Mesoporous Solids

AbstractThis paper describes the preparation and characterization of MgO and ZnO-based catalysts, pure and mixed in different proportions, supported on γ-Al2O3. Their catalytic performance was studied in the transesterification of soybean oil and castor oil with methanol and butanol, attempting to produce biodiesel. XRD (X-ray diffraction), SEM–EDS (scanning electron microscopy–energy dispersive X-ray spectroscopy), CO2-adsorption and N2-adsorption allowed characterizing the prepared catalysts. The characterization results were in all cases consistent with mesoporous solids with high specific surface area. All the catalysts exhibited good results, especially in the transesterification of castor oil using butanol. For this reaction, the reuse was tested, maintaining high FABE (fatty acid butyl esters) yields after four cycles. This good performance can be attributed to the basic properties of the Mg species, and simultaneously, to the amphoteric properties of ZnO, which allow both triglycerides and free fatty acids to be converted into esters. Using these catalysts, it is possible to obtain second-generation biodiesel, employing castor oil, a raw material that does not compete with the food industry. In addition, butanol can be produced from renewable biomass.

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Magnetic Spinel Ferrite: An Efficient, Reusable Nano Catalyst for HMFSynthesis

Current Catalysis ◽

10.2174/2211544710666211119094247 ◽

2021 ◽

Vol 10 ◽

Author(s):

Jyoti Dhariwal ◽

Ravina Yadav ◽

Sheetal Yadav ◽

Anshu Kumar Sinha ◽

Chandra Mohan Srivastava ◽

...

Keyword(s):

Catalytic Activity ◽

Surface Area ◽

Heterogeneous Catalysts ◽

Spinel Ferrite ◽

Active Surface ◽

Catalytic Performance ◽

Ferrite Nanoparticles ◽

Precipitation Method ◽

Magnetic Characteristics ◽

Nano Catalyst

Aim: In the present work, the preparation and catalytic activity of spinel ferrite [MFe2O4; M = Fe, Mn, Co, Cu, Ni] nanoparticles to synthesize 5-hydroxymethylfurfural (HMF) have been discussed. Background: Ferrites possess unique physicochemical properties, including excellent magnetic characteristics, high specific surface area, active surface sites, high chemical stability, tunable shape and size, and easy functionalization. These properties make them essential heterogeneous catalysts in many organic reactions. Objective: This study aims to synthesize a series of transition metal ferrite nanoparticles and use them in the dehydration of carbohydrates for 5-hydroxymethylfurfural (HMF) synthesis. Method: The ferrite nanoparticles were prepared via the co-precipitation method, and PXRD confirmed their phase stability. The surface area and the crystallite size of the nanoparticles were calculated using BET and PXRD, respectively. Result: The easily prepared heterogeneous nanocatalyst showed a significant catalytic performance, and among all spinel ferrites, CuFe2O4 revealed maximum catalytic ability. Conclusion: Being a heterogeneous catalyst and magnetic in nature, ferrite nanoparticles were easily recovered by using an external magnet and reused up to several runs without substantial loss in catalytic activity. Others: HMF was synthesized from fructose in a good yield of 71%.

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Self-solidification ionic liquids as heterogeneous catalysts for biodiesel production

Green Chemistry ◽

10.1039/c9gc00195f ◽

2019 ◽

Vol 21 (11) ◽

pp. 3182-3189 ◽

Cited By ~ 9

Author(s):

Xiaocheng Lin ◽

Xiaomei Ling ◽

Jinyi Chen ◽

Meichen Li ◽

Tongwen Xu ◽

...

Keyword(s):

Catalytic Activity ◽

Ionic Liquids ◽

Heterogeneous Catalysts ◽

Biodiesel Production ◽

High Catalytic Activity ◽

Excellent Stability

A simple and mild method has been developed to fabricate solid ionic liquids with high catalytic activity and excellent stability for efficient biodiesel production.

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Synthesis of Au@Pt Core–Shell Nanoparticles as Efficient Electrocatalyst for Methanol Electro-Oxidation

Nanomaterials ◽

10.3390/nano9111644 ◽

2019 ◽

Vol 9 (11) ◽

pp. 1644

Author(s):

Higareda ◽

Kumar-Krishnan ◽

García-Ruiz ◽

Maya-Cornejo ◽

Lopez-Miranda ◽

...

Keyword(s):

Catalytic Activity ◽

Electrocatalytic Activity ◽

Heterogeneous Catalysts ◽

Precursor Solution ◽

Catalytic Performance ◽

Atomic Ratio ◽

Core Shell ◽

Shell Nanoparticles ◽

Synthesis Strategy ◽

Electro Oxidation

Bimetallic Au@Pt nanoparticles (NPs) with Pt monolayer shell are of much interest for applications in heterogeneous catalysts because of enhanced catalytic activity and very low Pt-utilization. However, precisely controlled synthesis with uniform Pt-monolayers and stability on the AuNPs seeds remain elusive. Herein, we report the controlled deposition of Pt-monolayer onto uniform AuNPs seeds to obtain Au@Pt core–shell NPs and their Pt-coverage dependent electrocatalytic activity for methanol electro-oxidation. The atomic ratio between Au/Pt was effectively tuned by varying the precursor solution ratio in the reaction solution. The morphology and atomic structure of the Au@Pt NPs were analyzed by high-resolution scanning transmission electron microcopy (HR-STEM) and X-ray diffraction (XRD) techniques. The results demonstrated that the Au@Pt core–shell NPs with Pt-shell thickness (atomic ratio 1:2) exhibit higher electrocatalytic activity for methanol electro-oxidation reaction, whereas higher and lower Pt ratios showed less overall catalytic performance. Such higher catalytic performance of Au@Pt NPs (1:2) can be attributed to the weakened CO binding on the Pt/monolayers surface. Our present synthesis strategy and optimization of the catalytic activity of Au@Pt core–shell NPs catalysts provide promising approach to rationally design highly active catalysts with less Pt-usage for high performance electrocatalysts for applications in fuel cells.

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Natural Clay of Pasaman Barat Enriched by CaO of Chicken Eggshells as Catalyst for Biodiesel Production

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.15.3.8097.662-673 ◽

2020 ◽

Vol 15 (3) ◽

pp. 662-673

Author(s):

Syukri Syukri ◽

Kevin Septioga ◽

Syukri Arief ◽

Yulia Eka Putri ◽

Mai Efdi ◽

...

Keyword(s):

Catalytic Activity ◽

Broiler Chicken ◽

Catalytic Performance ◽

Biodiesel Production ◽

Main Peak ◽

X Ray Diffraction ◽

X Ray ◽

Activity Test ◽

West Sumatra ◽

The Fourier Transform

This study uses broiler chicken eggshells to enhance catalytic activity of clay obtained from Pasaman Barat (West Sumatra, Indonesia) in lab-scale biodiesel production. The eggshell is a source of calcium oxide (CaO) which operates as a catalyst when mixed with the clay (Ca-Clay). Two other catalysts were also prepared as comparisons by 1) heating the clay at 800 oC for 6 hours (P-Clay), 2) mixing the P-Clay with KOH (K-Clay). An X-ray Fluorescence (XRF) showed the elemental composition of Ca-Clay contained Ca, Si, Al, and Fe. An X-ray Diffraction (XRD) showed the formation of highly crystalline CaO in the Ca-Clay with the main peak at 2θ = 37.27o. The Fourier Transform Infra Red (FTIR) spectrum showed an absorption peak in the range of 700-900 cm-1 indicating Ca-O stretching demonstrating successful incorporation of the CaO into the clay. The catalytic activity test showed the Ca-Clay had a higher catalytic performance than P-Clay and K-Clay in terms of the yield of biodiesel produced (73%). Copyright © 2020 BCREC Group. All rights reserved

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The Catalytic Performance Comparison of Two Different Pyrrolidone Type Ionic Liquid in Biodiesel Production from Soybean Oil

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.641-642.890 ◽

2013 ◽

Vol 641-642 ◽

pp. 890-893

Author(s):

Yuan Dong Xu

Keyword(s):

Ionic Liquid ◽

Catalytic Activity ◽

Methyl Ester ◽

Soybean Oil ◽

Optimal Condition ◽

Catalytic Performance ◽

Performance Comparison ◽

Biodiesel Production ◽

Reaction Conditions ◽

High Level

Two different ionic liquid of the N-(3-sulfonic group) propyl pyrrolidone hydrosulfate ([C3SO3Hnhp]HSO4) and the 2-pyrrolidone hydrosulfate ([Hnhp]HSO4) have been synthesized and used as catalyst for the biodiesel production from the soybean oil. The former exhibited better catalytic performance than that of the later one and the reaction conditions corresponding to [C3SO3Hnhp]HSO4 were optimized. Under the optimal condition the yield of methyl ester reached 93.6% and after repeatedly used for four times the catalytic activity for [C3SO3Hnhp]HSO4 still maintained in a high level.

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Direct Synthesis of DMC from CO2 and CH3OH over CexZr 1-x-0.1Y 0.1 O2 Catalysts

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.287-290.1632 ◽

2011 ◽

Vol 287-290 ◽

pp. 1632-1635 ◽

Cited By ~ 1

Author(s):

Zhi Fang Zhang ◽

Rui Bing Wang ◽

Xiang Rong Ma

Keyword(s):

Solid Solution ◽

Catalytic Activity ◽

Solid Solutions ◽

Dimethyl Carbonate ◽

Direct Synthesis ◽

Sol Gel ◽

Catalytic Performance ◽

Solid Solution Series ◽

Calcination Temperatures ◽

Bimodal Pore Structure

The solid solution series CexZr(1-x-0.1)Y0.1O2 with various x values was prepared by the citric acid sol-gel method, using cerium and zirconium nitrides as precursors, respectively.The characterization results of the XRD, N2 sorption measurements indicated that the physical properties of the solid solutions were significantly affected by the x values in CexZr(1-x-0.1)Y0.1O2 and the calcination temperatures. These solid solutions can be used as catalyst for the direct synthesis of dimethyl carbonate from CH3OH and CO2. Results indicated that the catalytic activity for DMC synthesis was influenced by the structure of the solid solutions and the x values in CexZr(1-x-0.1)Y0.1O2. The optimized Ce0.5Zr0.4Y0.1O2 with bimodal pore structure exhibited higher catalytic performance to DMC synthesis.

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