POLY(AMINOMETHYLENEPHOSPHONIC) ACID FOR SOLVENT EXTRACTION OF METAL IONS

Diaminododecyltetramethylenetetraphosphonic acid (DADTMTPA) has been investigated in liquid - liquid extraction of Zn (II) and Cu (II) in acetate media. The extraction of both cations was carried out in different media with the addition of CH3COONa, CH3COOH, HCl and H2SO4 at different pH values. The maximum extraction yield for copper is 70% after addition of 10 mg of sodium acetate and for zinc is 30% after addition of acetic acid at pHi = 5.5, in one step

Synthesis and proton conduction properties of lanthanide amino-sulfophosphonates

Crystalline acid-functionalized metal phosphonates are potential candidates as proton conducting electrolytes. Their frameworks can be chemically modified to contain proton carriers such as acidic groups (P-OH; -SO3H, -COOH,…) and guest molecules (H2O, NH3,…) that generates hydrogen bond networks stable in a wide range of temperature [1,2]. In this work, focus is laid on properties derived from the combination of lanthanide ions with the amino-sulfophosphonate ligand (H2O3PCH2)2-N-(CH2)2-SO3H. Hightrough-put screening was followed to reach the optimal synthesis conditions under solvothermal conditions at 140 ºC. Isolated polycrystalline solids, Ln[(O3PCH2)2-NH-(CH2)2-SO3H].2H2O (Ln= La, Pr and Sm), crystallize in the monoclinic (La) and orthorhombic (Pr and Sm) systems with unit cell volume of ~2548 Å3. Preliminary proton conductivity measurements for Sm derivative have been carried out between 25º and 80 ºC at relative humidity (RH) values of 70 % and 95 %. The sample exhibits enhanced conductivity at high RH and T (Figure 1) and constant activation energies of 0.4 eV, typical of a Grothuss mechanism of proton.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. FQM-1656; MAT2013-41836-

Tuning Proton Conductivity Properties of Lanthanide Amino-Sulfophosphonates-Loaded Nafion Composite Membranes

Polymer-based electrolytes in proton exchange membrane fuel cells (PEMFCs) utilize acidic groups as proton carriers and hydrogen bonding networks as proton-conducting pathways to facilitate proton transport. Crystalline acid-functionalized metal phosphonates are potential proton conductors while maintaining a high hydration degree below 100 °C. This property may be combined with Nafion-like polymers which tend to dehydrate at the operating conditions of PEMFCs [1,2]. In this work, preliminary results of the preparation of lanthanide amino-sulfophosphonates-loaded Nafion composites membranes and the corresponding electrical properties are reported. Synthesis conditions of lanthanide derivatives were optimized following a hightrough-put screening at 140 °C. Their crystal structures, solved from synchrotron X-ray powder diffraction data, corresponds to layered frameworks where the acidic groups, -CPO3H or -SO3H, point toward the interlamellar region interacting by H-bond with the lattice water. The composites were prepared by mixing the metal phosphonates with Nafion solution at different loadings. The membranes were characterized by SEM, XRD and FT-IR. A study of the proton conductivity as a function of the composite membranes was carried out at 90 °C and 95% RH. Referencias [1] Y. Gao, R. Broersen, W. Hageman, N. Yan, M. C. Mittelmeijer-Hazeleger, G. Rothenberg, S. Tanase. J. Mater. Chem. A, 2015, 3, 22347–22352. [2] A. Cabeza, P. Olivera-Pastor, R. M. P. Colodrero. Tailored Organic-Inorganic Materials, Brunet, E., Colón, J.L., Clearfield, A., Eds.; John Wiley & Sons, Inc. 2015; Ch. 4, 137−191.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

PREDICTION OF PREDOMINANT CONFIGURATION IN THE ENANTIOSELECTIVE REDUCTION OF -KETOACID DERIVATES WITH BAKER'S YEAST USING NEURAL NETWORKS

International audienceCorrelation between chemical structure and enantioselectivity in baker's yeast reduction of a set of carbonyl compounds was constructed by means of a multi-layer neural network using the back-propagation algorithm. To evaluate the predictive power of the neural network (NN) model, the cross-validation procedure was used, 88 % of the reactions were correctly predicted

SYNTHESIS OF DIPHOSPHONIUM SALTS AND THEIR APPLICATION IN EPOXY BENTONITE NANOCOMPOSITE

The surface properties of bentonite can be greatly modified by simple ion-exchange reaction between organic surfactant cations and the adsorbat

SYNTHESIS OF PHOSPHONIC ACIDS& PREPARATION OF CATALYSTS

The first part of this study includes the synthesis of four classes of phosphonic acids under microwave irradiations following either the michaelis-arbuzov or irani mechanism

Computational study of the chemical reactivity properties of bis (trimethyl tetrathiafulvalenyl) thiophene

The chemical reactivity of four bis (trimethyltetrathiafulvalenyl) thiophene is determined by its potential (electronic) energy (hyper) surface. All the quantum chemical calculations have been carried out using DFT level of theory, B3LYP functional and 6-31G(d,p) as basis set. Molecular electrostatic potential (MEP) and HOMO-LUMO energy levels have been performed. The local reactivity descriptor such as Fukui function is also performed to determine the reactive sites within the title molecules. The chemometric methods PCA and HCA were employed to find the subset of variables that could correctly classify the compounds according to their reactivity

EXTRACTION PAR POINT DE TROUBLE DES IONS BISMUTH ET ZYRCONYL. OPTIMISATION DU PROCEDE

Au-dela d'une temperature dite 'point de trouble' les solutions aqueuses de la plupart des tensioactis non ioniques polyéthoxylés se séparent en deux phases liquids en équilibre: le coaservat et la phase dilu

CATALYSIS BY TRIFLIC ACID: SYNTHESIS OF THE INDOLYLQUINONES AS POTENTIAL ANTITUMOR AGENT

International audienceTrifluoromethanesulfonic acid catalyzes efficiently the conjugate addition of indoles to p-benzoquinones under mild conditions affording the corresponding indolylquinones in high yields with high selectivity. In particular the poorly reactive menadione underwent reaction with indoles under similar conditions to give 3-indolylnaphthoquinones