"Preparação de blendas de PVDF/lignina kraft para aplicação em água de produção de petróleo"

Abstract

PVDF membranes with residual eucalyptus lignin extracted from the cellulose production process were prepared and characterized in which it was washed and modified by carboxymethylated reaction. Sea water and petroleum production water were used in the permeation test. In this way, membranes were prepared from polyvinylidene-polyvinylidene -(C2H2F2) -(PVDF) and lignin macromolecule -(C6C3)-in different mass percentages with solvent 1-methyl-2-pyrrolidone (C5H9NO) (NMP). The FTIR presented two important modifications for the modified lignin at 3400 and 1600 cm-1, in its TGA it stands out more thermal events and its solubility in water increased significantly. The membranes were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The increase in the percentage of lignin reduces the degree of crystallinity, the enthalpy of fusion and the thickness of the membrane, increasing the permeate flux and the porosity of the membranes. It also shows that, based on the results obtained from the permeate flux from 52.08 to 72.67 Lh-1.m-2for production water and from 263.93 ± 1.02 to 1871 ± 0.047 Lh-1.m-2for seawater, the membranes A, B, C, D and I present greater resistance to the passage of production water, a situation that is due to the fact that the membranes developed have a smaller pore size and quantity.