Procesos para la producción de papel y pulpa : de la naturaleza a la mesa

Fil: Boeykens, Susana. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Química; Argentina.Existen varios procesos para la producción de papel y esto depende del tipo de producto que se\nproduzca. Desde la elección de los árboles de los cuales se obtiene la celulosa hasta la calidad del\npapel y el tratamiento de los efluentes, las metodologías varían y los productos utilizados en el proceso\nimplican consecuencias diversas. ¿Cómo se fabrica el papel, cuáles son las opciones de fabricación\nexistentes y cuánto compromete cada tipo de producción y tratamiento al medio ambiente?

Defining New Parameters for Green Engineering Design of Treatment Reactors

This study proposes a green way to design Plug Flow Reactors (PFR) that use biodegradable polymer solutions, capable of contaminant retaining, for industrial wastewater treatment. Usually, to the design of a reactor, the reaction rate is determined by tests on a Continuous Stirred-Tank (CST), these generate toxic effluents and also increase the cost of the design. In this work, empirical expressions (called “slip functions”), in terms of the average concentration of the contaminant, were developed through the study of the transport behaviour of CrVI into solutions of xanthan gum. “In situ” XRμF was selected as a no-invasive micro-technique to determine local concentrations. Slip functions were used with laboratory experiments planned in similar conditions using Plug Flow Reactors, to obtain useful dimensionless parameters for the industrial design

Risk Analysis of Acute and Chronic Exposure to Arsenic of the Inhabitants in a District of Buenos Aires, Argentina

The arsenic occurrence in the water constitutes a serious world health concern due to its toxicity. Depending on the intensity and duration of exposure, this element can be acutely lethal or may have a wide range of health effects in humans and animals. In Argentina, the origin of arsenic is mainly natural, and related to different geological processes. The Argentinean concern about arsenic and its influence on human health dates back to the previous century. The disease ascribed to arsenic contamination was called ‘chronic regional endemic hydroarsenism’. It is produced by the consumption of water with high levels of this element. In our study, we focused in La Matanza district, a very populated site in the Buenos Aires Province. An increasing concern of the inhabitants of the area regarding health problems was detected. In order to establish a full view of arsenic exposure in the area, several matrices and targets were analyzed. As matrices, water and soil samples were analyzed. As targets, canine and human hair was studied. The aim of this study was to investigate acute and chronic exposure to arsenic of La Matanza inhabitants

Remoción de Iones Metálicos de Mezclas Binarias Usando Dolomita

In the present work we evaluated the use of dolomite as an alternative for the adsorption of lead and copper ions from their aqueous solutions. The possible interferences between them and the selectivity of the process were studied working with mixtures of these two ions in adsorption processes. From the analysis of the results it can be inferred that the adsorption of lead is not affected by the presence of copper, since no changes in its adsorption capacity are observed as the concentration of the other ion changes. Copper adsorption is not affected by the presence of lead up to a copper level of 130 mg / L. For higher concentrations of copper, the antagonistic competition of Pb is manifested. From the kinetic studies performed at an equimolar concentration of Pb (400 mg / L) and Cu (130 mg / L), it was observed that the presence of copper increases the time required to reach the equilibrium of lead adsorption, but its adsorption capacity is unchanged. For the adsorption of copper the equilibrium time was not modified by the presence of lead.Keywords: Competitive adsorption, binary mixtures, copper, lead

Agroindustrial Waste for Lead and Chromium Biosorption

There is a need to re-evaluate the residues generated in industrial processes for the production of new raw material, reducing the volume of waste. In this regard, the biosorption is a low-cost alternative method for treating effluents compared to conventional methods. The main objectives of this research were: the evaluation of the biosorbent capacity of six waste materials for the extraction of chromium(VI) and lead(II) ions from aqueous solutions and, the determination of the adsorption and kinetic parameters for the more efficient system. The materials evaluated were: peanut shell (Arachis hypagaea), sugarcane bagasse (Saccharum officinarum), avocado peel (Persea americana), pecan nutshell (Carya illinoinensis), wheat bran (Triticum aestivum) and banana peel (Mussa paradisiaca). The highest percentage of lead removal was obtained with wheat bran (89%). For chromium, the percentage was generally much lower compared with lead for all tested biosorbents, the banana peel being the most efficient with a 10% removal. The models that better describe the adsorption processes were: Langmuir and Freundlich. The pseudo-second order kinetic model allowed obtaining the parameters for both systems. The equilibrium time, in both systems, was reached after 60 minutes. The study of Fourier Transformed Infrared spectra and the results of desorption experiments allowed to hypothesize on the mechanisms involved in the adsorption of these metals

Evaluation of an Organic Waste Composting Device to Household Treatment

The performance of a plug-flow automated aerobic digester used with the compost of the Biodegradable Organic Waste (BOW) from a typical family at its generation rhythm was evaluated. During a 13 month assessment, 179.7 kg of BOW were treated and 106.7 kg of compost were obtained with a C:N ratio of 12 and an average concentration of N of about 2.72%. Additional tests enabled to assess the generation of stable and good quality compost according to the considered standards, suitable for using as organic fertilizer and other uses, such as biotreatments. The design, location and operational characteristics of the device have determined reduced leachate emissions, the absence of unpleasant odour generation and incidence of insects or other vectors, implying the viability of their use without affecting the user´s life quality. It could be an efficient alternative treatment for household BOW, from a technical, economic, energy, cultural and environmental point of view, easy to implement for users lacking in special training

Cotton Industry Waste as Adsorbent for Methylene Blue

Removing dyes used in the textile industry from the water bodies is a relevant task because of the importance of their high toxicity. The cotton industry waste is a big problem in the final disposal. Waste cotton fibrils were studied as adsorbent material to treat the coloured effluents of the textile industry. Washing with boiling water was determined as the most efficient method for cleaning. The material was physical characterized. After that, methylene blue adsorption tests were carried out to review the dry removal process at different pH. The Langmuir isotherm and the pseudo-second kinetic order models best described this adsorption process. The results would indicate that the process involve a chemisorptions

Transferencia y propiedad intelectual : Programa 211

Fil: Boeykens, Susana. Universidad de Buenos Aires. Facultad de Ingeniería. Laboratorio de Química de Sistemas Heterogéneos; ArgentinaFil: Francés, Mónica. Universidad de Buenos Aires. Secretaría de Ciencia y Técnica. Dirección de Vinculación Tecnológica; ArgentinaEn esta emisión, contamos con la participación de Fabio Nigra, Profesor Adjunto de la Cátedra de Historia de EE.UU., Gilda Bevilacqua y Mariana Piccinelli, ambas Doctorandas y Profesoras de Historia (UBA), para dialogar acerca del discurso histórico en el cine de Hollywood

Reusing Materials: Pb and Cr biosorption

The heavy metals such as chromium and lead are highly toxic and have high persistence in the environment. This has direct implications on the ecosystem and the health of populations not directly exposed to contaminated water. There is a need to reevaluate the residues originated in industrial processes for the production of new raw material, reducing the volume of waste. In this regard, the biosorption is an alternative method for treating effluents more economical compared to conventional methods. The main objectives of this research were: the evaluation of six waste materials biosorbent capacity for the extraction of Cr (VI) and Pb (II) ions from aqueous solutions and, the determination of the adsorption and kinetic parameters for the more efficient system. The materials evaluated were: peanuts shell (Arachis hypagaea), sugarcane bagasse (Saccharum officinarum), avocado peel (Persea americana), pecan nutshell (Carya illinoinensis), wheat bran (Triticum aestivum) and banana peel (Mussa paradisiaca). The highest percentage of lead removal was obtained with wheat bran (89%). For chromium, the percentage was generally much lower compared with lead for all tested biosorbents, being the most efficient the banana peel with a 10% of removal. The models better describes the adsorption processes were: Langmuir and Freundlich. The pseudo-second orden kinetic model allowed obtaining the parameters for both systems. The equilibrium time, in both systems, was reached after 60 minutes.Fil: Boeykens, Susana Patricia. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Química; ArgentinaFil: Saralegui, Andrea Beatriz. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Química; ArgentinaFil: Gobbi Miñones, Alejandro Ricardo. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Química; ArgentinaFil: Piol, María Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Química; Argentin