We synthesized Na(2)[B(12)H(12)] by a solid state procedure and thermal decomposition of Na[B(3)H(8)], and calculated from a first-principles approach the thermodynamic and structural properties. In particular, the calculated enthalpy of formation of the monoclinic structure, at T = 0 K, of -1086.196 kJ mol(-1) showed that it is a very stable compound. Therefore, in case it were formed during t...

In this paper, components of an industrial wastewater that cause operational problems during biological treatment were oxidized by UV light and hydrogen peroxide (UV/H202). Preoxidation of wastewater was shown to remove polyvinylpyrrolidone (PVP) and ethoxylate surfactant and increase overall biodegradability. Several UV intensities and hydrogen peroxide concentrations were tested to find optim...

Polyphenolic resol resins were obtained from an ethanolic extraction of green plantain peels (Musa paradisiaca) grown in Colombia. A synthesis was then performed by polycondensation in an alkaline pH solution in order to perform research on phenolic resin production with high mechanical performance. The polymers were characterized by DSC and TGA analyses and the resins showed a melting point of...

The study of Pb(II) binding to the system humic acid/goethite in acidic medium is reported in the present paper. From a macroscopic point of view, we have constructed the experimental sorption isotherms (using atomic absorption spectroscopy) and compared them with the prediction of the additivity rule. It is found that this system presents positive deviations, that is, the amount sorbed is abou...

We hypothesized that the sorption of polycyclic aromatic hydrocarbons (PAHs) to natural sediments and soils should consider both absorption into a biogenic/diagenetic organic carbon (OC) fraction and adsorption onto a combustion-derived, black carbon (BC) fraction. Here, two sets of literature data were reevaluated to illustrate that an OC absorbent and a BC adsorbenttogether can (1) account fo...

mesoporous tio2 has been prepared using a nonionic block copolymer (pluronic p-123) as structure-directing agent with sol-gel method. characterization of the product was carried out by means of x-ray diffraction (xrd), scanning electron microscopy (sem), thermogravimetry-differential scanning calorimetry (tg-dsc), nitrogen sorption isotherms, and uv-vis absorption spectroscopy. these analyses s...

The adsorption behaviour of Methyl violet and Auramine yellow from aqueous solution onto Stishovite clay was investigated as a function of parameters such as initial dye concentration, contact time, p and temperature. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms. Adsorption followed pseudo-second order model. The experimental data fitted well ...