Preparação e caracterização de biofilmes à base de manipueira para imobilização de caulinita intercalada com ureia

Abstract

The problem of industrial waste generation has aggravating mainly by the fact that only a small portion of that waste is properly treated and properly designed in suitable places. An example of waste with high pollution potential is manipueira, liquid effluent generated in large quantities in manihot processing for the production of flour and starch. Manipueira contains a large organic load in its composition, with high levels of residual starch, resulting in low yield of the extraction process. Another major environmental problem is the loss of nutrients applied to the soil through fertilizers, especially nitrogen, resulting from leaching processes by rain water and volatilization soil heating, which brings financial damage to farmers and environmental damage by excess nutrients carried to water bodies. Allying these two issues, the objective of this work was to produce biofilms based on pure manipueira, and too manipueira with incorporation of additives poly (vinyl alcohol) and sodium alginate, thus assessing the influence of these additives in the final characteristics of biofilms. After this step, we evaluated which of biofilms produced consistent characteristics obtained for the immobilization of kaolinite intercalated with urea, to evaluate this set as a slow release fertilizer nitrogen, which prioritizes the gradual release of the nutrient. From the characterization of cassava used, it was determined that it has a content of 3% starch in composition, thus the residue was used as filmogenic solution for the formation of biofilms.These biofilms were described and presented barrier properties to water vapor low, however, the biofilm manipueira and pure manipueira and manipueira with poly (vinyl alcohol) have good mechanical properties and high thermal stability. Biofilms manipueira with sodium alginate showed inferior mechanical characteristics to those cited above and with lower thermal stability. From the characteristics presented, the biofilm pure manipueira was chosen to be the means of immobilizing kaolinite intercalated with urea, which, besides the characterization performed as in other biofilms was also investigated the release of nitrogen through leaching tests and heating. It was observed that the leaching tests was not effective immobilization, losing 73.37% of the nitrogen already incorporated in the shortest time employed in the assay, however, a test of heating, the biofilm pure manipueira showed high immobilization to 170 ° C, with a loss of nitrogen of only 14.93%. The analysis suggests that biofilms based manipueira are a viable reuse of this waste, with good features, however, when employment is immobilization of kaolinite intercalated with urea requires a larger study looking at ways to reduce leaching losses.