Versatile Sulfathiazole-Functionalized Magnetic Nanoparticles as Catalyst in Oxidation and Alkylation Reactions

Catalyst design and surface modifications of magnetic nanoparticles have become attractive strategies in order to optimize catalyzed organic reactions for industrial applications. In this work, silica-coated magnetic nanoparticles with a core-shell type structure were prepared. The obtained material was successfully functionalized with sulfathiazole groups, which can enhance its catalytic features. The material was fully characterized, using a multi-technique approach. The catalytic performance of the as-synthesized material was evaluated in 1) the oxidation of benzyl alcohol to benzaldehyde and 2) the microwave-assisted alkylation of toluene with benzyl chloride. Remarkable conversion and selectivity were obtained for both reactions and a clear improvement of the catalytic properties was observed in comparison with unmodified γ-Fe2O3/SiO2 and γ-Fe2O3. Noticeably, the catalyst displayed outstanding magnetic characteristics which facilitated its recovery and reusability.

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Directed Evolution of a Homodimeric Laccase from Cerrena unicolor BBP6 by Random Mutagenesis and In Vivo Assembly

International Journal of Molecular Sciences ◽

10.3390/ijms19102989 ◽

2018 ◽

Vol 19 (10) ◽

pp. 2989 ◽

Cited By ~ 3

Author(s):

Ji Zhang ◽

Fuying Ma ◽

Xiaoyu Zhang ◽

Anli Geng

Keyword(s):

Directed Evolution ◽

Laccase Activity ◽

Catalytic Properties ◽

Random Mutagenesis ◽

Catalytic Performance ◽

Industrial Applications ◽

Subunit Interaction ◽

Cerrena Unicolor ◽

Protein Model

Laccases have great potential for industrial applications due to their green catalytic properties and broad substrate specificities, and various studies have attempted to improve the catalytic performance of these enzymes. Here, to the best of our knowledge, we firstly report the directed evolution of a homodimeric laccase from Cerrena unicolor BBP6 fused with α-factor prepro-leader that was engineered through random mutagenesis followed by in vivo assembly in Saccharomyces cerevisiae. Three evolved fusion variants selected from ~3500 clones presented 31- to 37-fold increases in total laccase activity, with better thermostability and broader pH profiles. The evolved α-factor prepro-leader enhanced laccase expression levels by up to 2.4-fold. Protein model analysis of these variants reveals that the beneficial mutations have influences on protein pKa shift, subunit interaction, substrate entrance, and C-terminal function.

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Impact of amine- and phenyl-functionalized magnetic nanoparticles impacts on microwave-assisted extraction of essential oils from root of Berberis integerrima Bunge

Journal of Applied Research on Medicinal and Aromatic Plants ◽

10.1016/j.jarmap.2018.03.007 ◽

2018 ◽

Vol 10 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Hamid Hashemi-Moghaddam ◽

Majid Mohammadhosseini ◽

Zahra Azizi

Keyword(s):

Magnetic Nanoparticles ◽

Essential Oils ◽

Microwave Assisted Extraction ◽

Microwave Assisted ◽

Assisted Extraction ◽

Functionalized Magnetic Nanoparticles

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Ag2O–MnO2/Graphene Oxide Nanocomposite

10.32545/encyclopedia202007.0007.v1 ◽

2020 ◽

Author(s):

Farooq Syed ◽

Mujeeb Khan ◽

Mohammed Rafi Shaik ◽

Mufsir Kuniyil ◽

M Rafiq Siddiqui ◽

...

Keyword(s):

Catalytic Properties ◽

Specific Activity ◽

Catalytic Efficiency ◽

Cost Effective ◽

Catalytic Performance ◽

Industrial Applications ◽

Recoverable Catalyst ◽

Aerial Oxidation ◽

Milling Method ◽

State Mixing

In this study, we reported the eco-friendly fabrication of Ag2O–MnO2/GRO nanocomposites by the solid-state mixing of separately prepared GRO and Ag2O–MnO2 NPs using ball milling method, a mechanochemical approach. The prepared material was studied for the catalytic effect of GRO in the system for the aerial oxidation of a variety of alcohols. It was found that the (1%)Ag2O–MnO2/(5 wt.%)GRO nanocatalyst demonstrated a high conversion ability (~100%) and excellent selectivity in the presence of O2 as a clean oxidant. The higher catalytic properties of the nanocomposite were attributed to the presence of GRO, which exhibited extraordinary catalytic properties like improved surface area, excellent chemical compatibility, and stability, as well as the introduction of several defects in the obtained nanocomposite that enhance the catalytic performance. The specific activity of 13.3 mmol·g−1·h−1 is obtained for the catalyst i.e. (1%)Ag2O–MnO2/(5 wt.%)GRO, which is reportedly superior to the various other catalysts previously reported in the literature for the same conversion reaction. Our catalytic strategy was highly selective, producing only desired products with no over-oxygenation to carboxylic acids. The merits of our catalytic methodology were: (a) facile process, (b) inexpensive and clean oxidant, (c) no surfactants or nitrogenous bases were required, (d) mild catalytic conditions, (e) cost-effective recoverable catalyst, (f) complete convertibility, (g) full selectivity, (h) rapid process, and (i) applicable to virtually all types of alcohols. So, these highlights made this catalytic strategy to be highly applicable in the industrial applications for manufacturing of carbonyls. To the best of our knowledge, this was the first study of utilizing Ag2O–MnO2/GRO composite as a catalyst for the oxidation of alcohols, highlighting the catalytic efficiency of GRO.

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Microwave hydrothermal synthesis, characterisation, and catalytic performance of Zn1−x MnxO in cellulose conversion

Chemical Papers ◽

10.2478/s11696-013-0468-8 ◽

2014 ◽

Vol 68 (9) ◽

Author(s):

Maria Bernardi ◽

Vinícius Araújo ◽

Caue Ribeiro ◽

Waldir Avansi ◽

Elson Longo ◽

...

Keyword(s):

Catalytic Properties ◽

Catalytic Performance ◽

Acid Sites ◽

Weak Acid ◽

Spherical Nanoparticles ◽

Hydrothermal Route ◽

Cellulose Conversion ◽

Microwave Assisted ◽

Microwave Hydrothermal ◽

Plate Morphology

AbstractWurtzite-type Zn1−x MnxO (x = 0, 0.03, 0.05, 0.07) nanostructures were successfully synthesised using a simple microwave-assisted hydrothermal route and their catalytic properties were investigated in the cellulose conversion. The morphology of the nanocatalysts is dopant-dependent. Pure ZnO presented multi-plate morphology with a flower-like shape of nanometric sizes, while the Zn0.97Mn0.03O sample is formed by nanoplates with the presence of spherical nanoparticles; the Zn0.95Mn0.05O and Zn0.93Mn0.07O samples are mainly formed by nanorods with the presence of a small quantity of spherical nanoparticles. The catalyst without Mn did not show any catalytic activity in the cellulose conversion. The Mn doping promoted an increase in the density of weak acid sites which, according to the catalytic results, favoured promotion of the reaction.

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Functionalized magnetic nanoparticles for biomedical applications

Current Pharmaceutical Design ◽

10.2174/1381612821666151027151702 ◽

2015 ◽

Vol 21 (42) ◽

pp. 6038-6054 ◽

Cited By ~ 8

Author(s):

Dragoș Gudovan ◽

Paul Balaure ◽

Dan Mihăiescu ◽

Adrian Fudulu ◽

Bogdan Purcăreanu ◽

...

Keyword(s):

Magnetic Nanoparticles ◽

Biomedical Applications ◽

Functionalized Magnetic Nanoparticles

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Surface modifications of ceramic materials using excimer lasers: influence of plasma formation and materials properties on possible industrial applications

10.1117/12.144548 ◽

1993 ◽

Author(s):

K. Schutte ◽

Hans W. Bergmann ◽

Emil Schubert ◽

Robert Queitsch

Keyword(s):

Surface Modifications ◽

Ceramic Materials ◽

Industrial Applications ◽

Plasma Formation ◽

Excimer Lasers ◽

Materials Properties

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Influence of the Reduction Temperature and the Nature of the Support on the Performance of Zirconia and Alumina-Supported Pt Catalysts for n-Dodecane Hydroisomerization

Catalysts ◽

10.3390/catal11010088 ◽

2021 ◽

Vol 11 (1) ◽

pp. 88

Author(s):

Diana García-Pérez ◽

Maria Consuelo Alvarez-Galvan ◽

Jose M. Campos-Martin ◽

Jose L. G. Fierro

Keyword(s):

Catalytic Activity ◽

Surface Area ◽

Catalytic Properties ◽

Catalytic Performance ◽

Major Influence ◽

Pt Catalysts ◽

Reduction Temperature ◽

Metal Dispersion ◽

Tungsten Oxides ◽

Supported Pt Catalysts

Catalysts based on zirconia- and alumina-supported tungsten oxides (15 wt % W) with a small loading of platinum (0.3 wt % Pt) were selected to study the influence of the reduction temperature and the nature of the support on the hydroisomerization of n-dodecane. The reduction temperature has a major influence on metal dispersion, which impacts the catalytic activity. In addition, alumina and zirconia supports show different catalytic properties (mainly acid site strength and surface area), which play an important role in the conversion. The NH3-TPD profiles indicate that the acidity in alumina-based catalysts is clearly higher than that in their zirconia counterparts; this acidity can be attributed to a stronger interaction of the WOx species with alumina. The PtW/Al catalyst was found to exhibit the best catalytic performance for the hydroisomerization of n-dodecane based on its higher acidity, which was ascribed to its larger surface area relative to that of its zirconia counterparts. The selectivity for different hydrocarbons (C7–10, C11 and i-C12) was very similar for all the catalysts studied, with branched C12 hydrocarbons being the main products obtained (~80%). The temperature of 350 °C was clearly the best reduction temperature for all the catalysts studied in a trickled-bed-mode reactor.

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