Separation of N–C5H12–C9H20 Paraffins Using Boehmite by Inverse Gas Chromatography

The separation of a mixture of C5–C9 n-paraffins was achieved by Inverse Gas Chromatography (IGC) by using boehmite; AlO(OH), in a packed column with short exposure times and temperatures; from 45 °C to 52 °C. The boehmite was characterized by XRD; ATG; SEM; IR spectroscopy and N2 adsorption. The material exhibited a low crystalline boehmite (AlOOH) structure and presented high hydration (pseudoboehmite). The reverse gas chromatography measurements showed that the elution temperatures of the C5–C9 n-paraffins were low compared with those obtained for other adsorbents. The differential heat of adsorption values ensures the satisfactory separation of the components in the C5–C9 mixture under suitable chromatographic conditions

Separation of N–C₅H₁₂–C₉H₂₀ Paraffins Using Boehmite by Inverse Gas Chromatography

The separation of a mixture of C5−C9 n-paraffins was achieved by Inverse Gas Chromatography (IGC) by using boehmite; AlO(OH), in a packed column with short exposure times and temperatures; from 45 °C to 52 °C. The boehmite was characterized by XRD; ATG; SEM; IR spectroscopy and N2 adsorption. The material exhibited a low crystalline boehmite (AlOOH) structure and presented high hydration (pseudoboehmite). The reverse gas chromatography measurements showed that the elution temperatures of the C5−C9 n-paraffins were low compared with those obtained for other adsorbents. The differential heat of adsorption values ensures the satisfactory separation of the components in the C5−C9 mixture under suitable chromatographic conditions

CHARACTERIZATION AND USE OF A CUBAN MINERAL IN ELIM INATION OF CRYSTAL VIOLET FROM AQUEOUS SOLUTION

ABSTRACT: A Cuban mineral was used to evaluate its adsorption capacity of crystal violet (CV) from aqueous solutions. The mineral was characterized by several physicochemical techniques. Both N2 adsorption-desorption isotherm at 77K, fitted with the Brunnauer-Emmet-Teller model, and the results of the average pore distribution revealed that the Cuban mineral used in this study is a mesoporous material. The FTIR spectrum indicated a high content of carbonate species; however, the XPS spectrum also revealed the presence of silicon species on the surface of the adsorbent, which suggests the coexistence both carbonate and silicate species in the raw material. The efficiency for CV removal, the role of the contact time and of the initial concentrations of the adsorbate was evaluated in this study. The adsorption kinetic was fitted with the pseudo second order model. This result indicated that the adsorption mechanism was through chemisorption process between CV and Cuban mineral. The results showed that CV adsorption isotherm was best described by the Langmuir model. The adsorption capacity for CV was 55.63 mg/g. The abundant deposits, low cost and easy access make of mineral SAN1 a good natural adsorbent to treat large volumes of dye polluted waters

Compilación de Proyectos de Investigacion de 1984-2002

Instituto Politecnico Nacional. UPIICS