Kinetic Model for the Direct Conversion of CO/CO into Light Olefins over an InO-ZrO/SAPO-34 Tandem Catalyst.

An original kinetic model is proposed for the direct production of light olefins by hydrogenation of CO/CO (CO) mixtures over an InO-ZrO/SAPO-34 tandem catalyst, quantifying deactivation by coke. The reaction network comprises 12 individual reactions, and deactivation is quantified with expressions dependent on the concentration of methanol (as coke precursor) and HO and H (as agents attenuating coke formation). The experimental results were obtained in a fixed-bed reactor under the following conditions: InO-ZrO/SAPO-34 mass ratio, 0/1-1/0; 350-425 °C; 20-50 bar; H/CO ratio, 1-3; CO/CO ratio, 0-1; space time, 0-10 g h mol, 0-20 g h mol; time, up to 500 h; HO and CHOH in the feed, up to 5% vol.

Study of the Effect of ZnO Functionalization on the Performance of a Fully Formulated Engine Oil.

The automotive sector is demanding higher specifications to achieve maximum efficiency; in this sense a new generation of lubricants with higher thermo-oxidative stability and superior tribological properties is being explored. The formulation of nanolubricants based on the nature of different nanomaterials is one of the most recent approaches, with several gaps to cover, such as dispersion stability, related to the compatibility of proposed nanomaterials with conventional additives and baseoils used in lubricant formulation. This study evaluated the effect of ZnO nanomaterial dispersed in a commercial engine oil using two different approaches; the use of surfactant and nanomaterial surface functionalization to promote higher stability and lower cluster size.

Flow Boiling Heat Transfer; Experimental Study of Hydrocarbon Based Nanorefrigerant in a Vertical Tube.

Flow boiling is a complex process but very efficient for thermal management in different sectors; enhancing flow boiling heat transfer properties is a research field of great interest. This study proposes the use of various nanomaterials, carbon-based materials, and metal oxides; in n-pentane as a hydrocarbon-based refrigerant to enhance the flow boiling heat transfer coefficient. This thermal property has been experimentally evaluated using a vertical evaporation device of glass with an internal diameter of 20 mm.

Conditions for the Joint Conversion of CO and Syngas in the Direct Synthesis of Light Olefins Using InO-ZrO/SAPO-34 Catalyst.

The conditions for promoting the joint conversion of CO and syngas in the direct synthesis of light olefins have been studied. In addition, given the relevance for the viability of the process, the stability of the InO-ZrO/SAPO-34 (InZr/S34) catalyst has also been pursued. The CO+CO (CO ) hydrogenation experimental runs were conducted in a packed bed isothermal reactor under the following conditions: 375-425 °C; 20-40 bar; space time, 1.

Combined Ex and In Situ Measurements Elucidate the Dynamics of Retained Species in ZSM-5 and SAPO-18 Catalysts Used in the Methanol-to-Olefins Reaction.

The dynamics of the retained species on ZSM-5 and SAPO-18 catalysts are studied by using a combination of temperature-programmed desorption/oxidation, ex situ analysis, and in situ FTIR spectroscopic measurements over the entire conversion range, using fixed-bed and spectroscopic cell reactors, in continuous and discontinuous mode. The results point to the appropriateness of the combined methodologies to track the interconversion of active into deactivating species. A statistically relevant (supported by linear regression and multivariate analysis) association of the observations is found by using the different complementary methodologies.

Crystal structure of K0.75[Fe(II) 3.75Fe(III) 1.25(HPO3)6]·0.5H2O, an open-framework iron phosphite with mixed-valent Fe(II)/Fe(III) ions.

Single crystals of the title compound, potassium hexa-phosphito-penta-ferrate(II,III) hemihydrate, K0.75[Fe(II) 3.75Fe(III) 1.

A direct reaction approach for the synthesis of zeolitic imidazolate frameworks: template and temperature mediated control on network topology and crystal size.

The direct acid-base reaction between ZnO/CoO/Co(OH)(2) and imidazolic ligands under moderate heating (100-160 °C), in a closed vessel, leads to the generation of the corresponding zinc/cobalt-imidazolates in a high yield (87-97%) in which network topology is controlled by the addition of small amounts of structure directing agents. Moreover, the fine tuning of the thermal process at the synthetic stage permits us to increase the crystal size, and even to grow X-ray quality single crystals.

Open-framework copper adeninate compounds with three-dimensional microchannels tailored by aliphatic monocarboxylic acids.

A series of isostructural copper(II) coordination polymers containing the nucleobase adenine and different monocarboxylic acids as bridging ligands, [Cu(2)(μ(3)-ade)(2)(μ(2)-OOC(CH(2))(n)CH(3))(2)]·xH(2)O (n from 0 to 5), have been prepared. Single-crystal X-ray analysis of acetate (n = 0) and butanoate (n = 2) compounds shows a covalent three-dimensional network in which the copper(II) centers are bridged by μ-N3,N7,N9-adeninato and μ-O,O'-carboxylato ligands, with crystallization water molecules trapped in the pores, which are decorated by the Watson-Crick faces of the adenine. The tunable permanent porosity of guest-free compounds was confirmed by gas adsorption measurements.

Microporous vanadyl-arsenate with the template incorporated exhibiting sorption and catalytic properties.

(C(5)H(14)N(2))[(VO)(3)(AsO(4))(HAsO(4))(2)(OH)].3H(2)O behaves as a microporous organically templated compound, with reversible adsorption and desorption of N(2) at 77 K, and as an extremely efficient catalyst that catalyzes selective sulfoxide formation from organic sulfides, under mild conditions.

Fe(AsO4): a new iron(III) arsenate synthesized from thermal treatment of (NH4)[Fe(AsO4)F].

The new orthorhombic Fe(AsO4) phase has been synthesized by thermal treatment at 525 degrees C of a new (NH4)[Fe(AsO4)F] compound, with a [Fe(AsO4)F]- skeleton showing channels where the ammonium cations are located. The crystal structure of Fe(AsO4) has been solved from single-crystal data. The structure is formed by layers of edge-sharing dimeric octahedra, and interconnected by chains of alternating FeO6 octahedra and AsO4 tetrahedra.