Extração líquido-líquido de ferro(III) e titânio(IV) pelo ácido bis-(2-etil-hexil) fosfórico (D2EHPA) em meio de ácido sulfúrico/ Liquid-liquid extraction (LLE) of Fe(III) and Ti(IV) by bis-(2-ethyl-hexyl) phosphoric acid (D2EHPA) in sulfuric acid medium
Resumo em inglês This work presents a study on the separation of Fe(III) and Ti(IV) from sulfuric acid leaching solutions of ilmenite (FeTiO3) using liquid-liquid extraction with D2EHPA in n-dodecane as extracting agent. The distribution coefficients (K D) of the elements related to free acidity and concentration of Fe(III) and Ti(IV) were determined. Free acidity was changed from 3x10-2 to 11.88 mol L-1 and D2EHPA concentration was fixed at 1.5 mol L-1. Recovery of final products as well (mais) as recycling of wastes generated in the process were also investigated. The LLE process as a feasible alternative to obtain high-purity TiO2.
Resumo em inglês The volatile compounds of raw and extruded bovine rumen, extracted by dynamic headspace, were separated by gas chromatography and analyzed by GC-MS. Raw and extruded materials presented thirty-two volatile compounds. The following compounds were identified in raw bovine rumen: heptane, 1-heptene, 4-methyl-2-pentanone, toluene, hexanal, ethyl butyrate, o-xylene, m-xylene, p-xylene, heptanal, limonene, nonanal, dodecane, tridecane, tetradecane, pentadecane, hexadecane, hept (mais) adecane and octadecane. The following compounds were identified in the extruded material: 1-heptene, 2,4-dimethylhexane, toluene, limonene, undecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane and nonadecane. Mass spectra of some unidentified compounds indicated the presence of hydrocarbons with branched chains or cyclic structure.