scholarly journals Catalytic use of layered materials for fine chemical syntheses

2019 ◽  
Vol 9 (1) ◽  
pp. 47-60 ◽  
Author(s):  
Sándor B. Ötvös ◽  
István Pálinkó ◽  
Ferenc Fülöp
Keyword(s):  
Layered Double Hydroxides ◽  
Layered Materials ◽  
Layered Compounds ◽  
Solid Materials ◽  
Fine Chemical ◽  
Layered Solid ◽  
Double Hydroxides

The present work reviews the catalytic use of layered solid materials for fine chemical syntheses with focus on layered double hydroxides, but including other classes of layered compounds of catalytic relevance.

scholarly journals Study of the textural properties of some layered double hydroxides

2013 ◽  
Vol 21 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Cornelia-Magda Puscasu ◽  
Carmen Gherasim ◽  
Dragos Mardare ◽  
Gabriela Carja
Keyword(s):  
Layered Double Hydroxides ◽  
Structural Characteristics ◽  
Chemical Species ◽  
Textural Properties ◽  
Layered Compounds ◽  
Layered Compound ◽  
X Ray Diffraction ◽  
Anionic Clays ◽  
Interlayer Region ◽  
Double Hydroxides

Abstract Layered double hydroxides (LDHs) are one of the nano ordered layered compounds. The importance of layered compound is based on their ability to retain chemical species with electrical charges compatible to those of the layers. They may be used in areas such as catalysis, industry, medicine, environmental protection, construction etc. Layered double hydroxides are anionic clays comprising positively charged layers with anions and water molecules intercalated in the interlayer region. The aim of this work was to obtain Cu and/or Ni substituted layered double hydroxides with different micromorphology characteristics. The obtained results pointed out that the relationship between LDHs composition and their textural properties can be controlled. The layered double hydroxides samples were fabricated by using direct coprecipitation method. Field Emission Scanning Electron Microscope (FE-SEM) and X-Ray Diffraction (XRD) analyses were used to study the textural characteristics and the structural characteristics of the samples.

Rationalization of liquid assisted grinding intercalation yields of organic molecules into layered double hydroxides by multivariate analysis

RSC Advances ◽  
2016 ◽  
Vol 6 (110) ◽  
pp. 108431-108439 ◽  
Author(s):  
E. Conterosito ◽  
M. Milanesio ◽  
L. Palin ◽  
V. Gianotti
Keyword(s):  
Multivariate Analysis ◽  
Layered Double Hydroxides ◽  
Organic Molecules ◽  
Molecular Descriptors ◽  
Layered Materials ◽  
Double Hydroxides

PCA, coupled to molecular descriptors, proved to be an effective tool to rationalize the mechanochemical intercalation yields of layered materials.

Preparation of hydroxy double salts exchanged by organic compounds

1998 ◽  
Vol 13 (4) ◽  
pp. 848-851 ◽  
Author(s):  
Hiroyuki Morioka ◽  
Hideyuki Tagaya ◽  
Masa Karasu ◽  
Jun-ichi Kadokawa ◽  
Koji Chiba
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Layered Double Hydroxides ◽  
Interlayer Spacing ◽  
Layered Materials ◽  
Exchange Reactions ◽  
Double Salts ◽  
Hydroxy Double Salts ◽  
Double Hydroxides ◽  
Positively Charged

Hydroxy double salts (HDS's) comprise a class of layered materials that are similar to layered double hydroxides (LDH's) and show a comparable intracrystalline reactivity. Their anion exchange reactions occur with preincorporated anions in the hydroxide layer and with anions bound as gegenions of the positively charged layers, respectively. In this study, nitrate and acetate anions of HDS's were exchanged with anionic monoand di-carboxylic acids, and we confirmed that interlayer spacing of HDS's increased depending on the size of mono- and di-carboxylic acids. Moreover, we have prepared photofunctional materials by exchange reaction with azobenzene-p-carboxylic acid and 4–4′-azobenzenedicarboxylic acid.

Removal and Extraction of Carboxylic Acids and Non-ionic Compounds with Simple Hydroxides and Layered Double Hydroxides

2020 ◽  
Vol 26 (6) ◽  
pp. 650-663 ◽  
Author(s):  
Luis E.G. Rodriguez ◽  
Alesandro Bail ◽  
Rodolfo O. Castillo ◽  
Gregorio G.C. Arízaga
Keyword(s):  
Carboxylic Acids ◽  
Layered Double Hydroxides ◽  
Layered Compounds ◽  
Industrial Processes ◽  
Liquid Media ◽  
Active Ingredients ◽  
Ionic Compounds ◽  
Biotechnological Processes ◽  
Double Hydroxides ◽  
Natural Component

Carboxylic acids are an important natural component as a final product or intermediates for syntheses. They are produced in plants, animals and also as products from biotechnological processes. This review presents the use of single hydroxide particles and layered double hydroxides as alternative adsorbents to remove carboxylic acids from liquid media. The proposal to use hydroxide particles is based on its affinity to adsorb or intercalate carboxylic acids. Besides, the change in properties of the adsorbate-sorbate product evinces that this intermediate can be used as a vehicle to transport and release carboxylic acids. Additional examples will also be presented to prove that layered hydroxides are capable of removing non-ionic compounds from wine, milk and tomato. The use of layered compounds to remove active ingredients could reduce the number of separations steps, costs and reduce or eliminate solvents, thus encouraging the design of industrial processes of separation using hydroxides particles.

Ti/ZnO–MxOy composites (M = Al, Cr, Fe, Ce): synthesis, characterization and application as highly efficient photocatalysts for hexachlorobenzene degradation

2015 ◽  
Vol 17 (40) ◽  
pp. 26690-26702 ◽  
Author(s):  
Shengjie Xia ◽  
Mengmeng Shao ◽  
Xiaobo Zhou ◽  
Guoxiang Pan ◽  
Zheming Ni
Keyword(s):  
Schiff Base ◽  
Layered Double Hydroxides ◽  
Schiff Base Complex ◽  
Layered Materials ◽  
Base Complex ◽  
Highly Efficient ◽  
Double Hydroxides

A series of novel organic–inorganic nanoscale layered materials were synthesized by intercalating the Ti-containing Schiff base complex into the interlayer of the ZnM layered double hydroxides (LDHs, M = Al, Cr, Fe, Ce).

Acceptorless amine dehydrogenation and transamination using Pd-doped layered double hydroxides

2018 ◽  
Author(s):  
Diana Ainembabazi ◽  
Nan An ◽  
Jinesh Manayil ◽  
Kare Wilson ◽  
Adam Lee ◽  
...  
Keyword(s):  
Layered Double Hydroxides ◽  
Oxidation States ◽  
Secondary Amines ◽  
Primary Amines ◽  
Acid Dissolution ◽  
Oxidative Amination ◽  
Strong Function ◽  
Excellent Activity ◽  
High Yields ◽  
Double Hydroxides

<div> <p>The synthesis, characterization, and activity of Pd-doped layered double hydroxides (Pd-LDHs) for for acceptorless amine dehydrogenation is reported. These multifunctional catalysts comprise Brønsted basic and Lewis acidic surface sites that stabilize Pd species in 0, 2+, and 4+ oxidation states. Pd speciation and corresponding cataytic performance is a strong function of metal loading. Excellent activity is observed for the oxidative transamination of primary amines and acceptorless dehydrogenation of secondary amines to secondary imines using a low Pd loading (0.5 mol%), without the need for oxidants. N-heterocycles, such as indoline, 1,2,3,4-tetrahydroquinoline, and piperidine, are dehydrogenated to the corresponding aromatics with high yields. The relative yields of secondary imines are proportional to the calculated free energy of reaction, while yields for oxidative amination correlate with the electrophilicity of primary imine intermediates. Reversible amine dehydrogenation and imine hydrogenation determine the relative imine:amine selectivity. Poisoning tests evidence that Pd-LDHs operate heterogeneously, with negligible metal leaching; catalysts can be regenerated by acid dissolution and re-precipitation.</p> </div> <br>

Antibiotic-anionic Clay Matrix Used for Drug Controlled Release

2018 ◽  
Vol 69 (2) ◽  
pp. 321-323
Author(s):  
Georgeta Zegan ◽  
Elena Mihaela Carausu ◽  
Loredana Golovcencu ◽  
Alina Sodor Botezatu ◽  
Eduard Radu Cernei ◽  
...  
Keyword(s):  
Controlled Release ◽  
Layered Double Hydroxides ◽  
Bioactive Molecules ◽  
Drug Controlled Release ◽  
Anionic Clays ◽  
Anionic Clay ◽  
Toxicological Studies ◽  
High Efficient ◽  
Clay Matrix ◽  
Double Hydroxides

Anionic clay matrix acting as drug controlled release system have shown in last years a great potential for delivery of bioactive molecules and chemical therapeutics. This organic-inorganic nanohybrid system is high efficient offering an excellent protection of intercalated compounds from degradation. Compared to other nanoparticles used in medical area, anionic clays type layered double hydroxides have found to be biocompatible according to toxicological studies. Ampicillin containing MgAlLDHs and ZnAlLDH samples have been prepared following two routes: anion-exchange procedure and reconstruction from calcined layered double hydroxides. Solid samples have been characterized by FTIR and SEM-EDX highlighting the alteration of pristine LDHs structure when the antibiotic is introduced in the interlayer gallery.

Sign in / Sign up

Export Citation Format

Share Document