Use of Ethylamine, Diethylamine and Triethylamine in the Synthesis of Zn,Al Layered Double Hydroxides

Abstract

Amines with two carbon atoms in the organic chain [ethylamine (EA), diethylamine (DEA), triethylamine (TEA)] have been used as precipitant agents to obtain a hydrotalcite-like compound with Zn (II) and Al (III) as layered cations and with nitrate anions in the interlayered region to balance the charge. This Layered Double Hydroxide was prepared following the coprecipitation method, and the effect on the crystal and particle sizes was studied. Also, the effect of submitting the obtained solids to hydrothermal post-synthesis treatment by conventional heating and microwave assisted heating were studied. The obtained solids were exhaustively characterized using several instrumental techniques, such as X-ray diffraction, Thermal Analysis (DTA and TG), Chemical Analysis, Infrared Spectroscopy (FT-IR), determination of Particle Size Distribution and BET-Surface area. Well crystallized solids were obtained showing two possible LDH phases, depending on the orientation of the interlayer anion with respect to the brucite-like layers. The results indicated that there is a certain influence of the amine, when used as a precipitating agent, and as a consequence of the degree of substitution, on the crystallinity and particle size of the final solid obtained. The LDHs obtained using TEA exhibited higher crystallinity, which was improved after a long hydrothermal treatment by conventional heating. Regarding the shape of the particles, the formation of aggregates in the former solid was detected, which could be easily disintegrated using ultrasound treatments, producing solid powder with high crystallinity and small particle size, with homogeneous size distribution.

Insight into chromium adsorption from contaminated soil using Mg/Al LDH-zeolite

“…This process is supported by the work of [ 48 ], which demonstrated the leaching of Mg 2+ from hydrotalcite and the ready interchange of interlayer carbonate with the adjacent solution, resulting in the generation of uranyl carbonate complexes. Besides, Misol et al (2022) [ 49 ] highlighted the difficulty in preventing the integration of carbonate anions into the interlayer space when using the coprecipitation method, underscoring the strong tendency of carbonate to associate with LDH layers. Moreover, the substantial BET surface area of MALZ (252.66 m 2 /g) augments its capacity for immobilization through a pore-filling mechanism.…”

Colours of the upper Neogene “Poznań Clays” in the light of sedimentological, mineralogical and nuclear methods

“…Un der ap pro pri ate re dox con di tions, car bon ate-rich FGS can yield goethite, while sul phate-rich FGS can trans form into both goethite and lepidocrocite (John son, 2014; Zhitova et al, 2016;Srivastava et al, 2021;Misol et al, 2022). There fore, taking into ac count the flu vial or i gin of the "Poznañ Clays" and the re flec tion po si tion (Figs.…”

A Themed Issue in Honor of Prof. Dr. Vicente Rives

“…This Special Issue has received eighteen contributions, six review papers [1][2][3][4][5][6], and twelve research papers [7][8][9][10][11][12][13][14][15][16][17][18]. Most of the papers originated from groups who have previously worked with Prof. Rives, but five of the contributions came from authors who had not previously worked with him [6,7,13,17,18].…”

“…The materials most studied by Prof. Rives throughout his career were LDHs. Therefore, it was not surprising that these materials were the basis of eight of the papers published in this Special Issue [2][3][4]10,11,[15][16][17]. Other materials included Ni-based catalysts [1], g-C 3 N 4 [5], mesoporous silica [6], MOFs [7], carbons [8,9], AlPO 4 [12], acid-modified clays [13], and porous aluminosilicates [17].…”

“…Rodríguez-Castellón et al reported on the esterification of levulinic acid to methyl levulinate, catalyzed by Zr-MOFs [7]; Monzón et al studied the production of H 2 and CNT from methane using bimetallic catalysts based on carbon [8], whilst Carriazo et al used carbon composites for the preparation of advanced supercapacitors [9]. Labajos et al explored new routes for the preparation of LDHs using various amines in the synthesis process [10], while Nebot-Díaz et al used LDH as precursors of nanoparticle black pigments for the ceramic industry [11]. Ciuffi et al used Zn-AlPO 4 as photocatalysts for the degradation of fipronil [12], and Cesteros et al used acid-modified clays as catalysts for the preparation of 5-hydroxymethylfurfural from glucose [13].…”