2015
Rosa Richards, Irais Gómez, Elena Otazo, Francisco Prieto, Juan Hernández, Gladys Linares, César González, Alberto Gordillo & Roberto Villagómez. High Mn2+ uptake by a new polyvinyl alcohol derivative: isotherm model análisis. Separation Science and Technology (Enero, 2015), Vol.50(2):233-244, Factor Impacto en JCR 2013: 1.164. ID: 950278 DOI:10.1080/01496395.2014.950278
Abstract
The transformation of Polyvinyl alcohol (PVA) into poly(vinyl phenylthionecarbamate) (PVA-PT) was upgraded to 35 g with 45% yield and 90% conversion degree. PVA-PT has shown high uptakes (93-96%) towards Mn2+ > Cu2+ > Cd2+ after 4 hours stirring at 20C in a batch procedure, towards 31-1600 mg/L concentration range. The material and its metal ion adducts were characterized by gravimetric analysis, IR, Raman, and SEM/EDS. An experimental design was applied to evaluate the influence of parameters on the Mn2+ removal efficiency by PVA-PT. The best results were achieved after 240 min, at 20C and concentrations higher than 187 mg/L. The 20C sorption isotherms were recorded for the PVA-PT/Mn2+ system at different particle sizes and dosages. The best experimental sorption capacity (qe = 343.76 mg/g) was reached at the lowest dose (0.05 g in 10 mL solution) and the highest concentration (1809.82 mg/L). Data fit Freundlich isotherm model (R2 = 0.9462, KF = 0.8625, N = 0.8271), indicative of a moderate affinity interaction PVA-PT/Mn+2. The kinetic isotherm models demonstrate chemisorption and bulk diffusion-controlled absorption into the material after 7 min.
Aerosol composition from Tlaxcoapan, Hidalgo in central Mexico
Fluorides and dental fluorosis in students from Tula de Allende Hidalgo, Mexico
Diseño de una prueba de biodegradabilidad anóxica de compuestos orgánicos en medio líquido