Advances in Environmental Technologies: Recycling and Sustainability Joint Session: Poster Session
Sponsored by: TMS Extraction and Processing Division, TMS Light Metals Division, REWAS Organizing Committee, TMS: Pyrometallurgy Committee, TMS: Recycling and Environmental Technologies Committee
Program Organizers: John Howarter, Purdue University; Mark Kennedy, Proval Partners SA; Naiyang Ma, ArcelorMittal; Elsa Olivetti, Massachusetts Institute of Technology; Randolph Kirchain, Massachusetts Institute of Technology

Monday 6:00 PM
February 27, 2017
Room: Hall B1
Location: San Diego Convention Ctr

D-4: Chronopotentiometry Applied to the Determination of Copper Transport Properties through a Cation-exchange Membrane: Kayo Barros1; Jorge Tenório1; Denise Espinosa1; Juliana de Jesus1; 1University of São Paulo (USP)
    Over the past several decades electrodialysis membranes have been employed for the removal of metals from galvanizing industry effluents. For the technical viability, it is useful to know some properties of the system to avoid, for example, precipitation of inorganic salts, destruction of the membranes and an increase in the energy consumption. The scope of the presente study is to use the chronopotentiometry method to determine the limiting current density, transition time and resistence of the cationic membrane HDX 100 using a simulated solution of the galvanizing industry effluent prepared with copper sulfate and sulfuric acid in different concentrations: 0.1; 0.5 and 1.0 g/L of Cu2+. The current-voltage curves obtained have the three regions clearly defined, which makes possible determine the limiting current and the membrane resistence. The chronopotentiometric curves were also effectively constructed and transition times were determined, which comproves the success of the method used in this work.

D-5: Effect of Flow Rate on Metals Adsorption of Synthetic Solution Using Chelating Resin Dowex XUS43605 in Column Experiments: Isadora Perez1; Mónica Correa1; Flávia Silvas1; Jorge Tenório1; Denise Espinosa1; 1University of São Paulo
    In view of the rising generation of wastewater containing metals, sustainable and clean techniques to recover them are being researched. Thus, this study investigates the adsorption of the metals aluminum, cobalt, chromium, copper, iron (III), magnesium, manganese, nickel and zinc in a produced effluent in nickel mining by chelating ion exchange resin Dowex XUS43605. The resin was tested in columns experiments, analyzing the flow rate parameter, for pH 1.5 and at 20ºC. The concentration of metal in solution was obtained by the technique of x-ray fluorescence spectrometry energy dispersive (EDX). The results showed that breakthrough by some metals (aluminum, manganese and zinc) reached brokenthrough the initiation of the feed, while the breakthrough of copper began later. For column elution tests were used sulfuric acid first followed by ammonium hydroxide. Therefore, the study showed that the ion exchange resin can be used to treat effluents in particular mining.

D-6: Evaluation of the Silver Recovery from Solid Industrial Wastes in an Electrochemical Reactor: Pedro Ramirez Ortega1; Victor Reyes Cruz2; Maria Veloz Rodriguez2; Laura Garcia Hernandez1; 1Universidad Tecnológica de Tulancingo; 2Universidad Autónoma del Estado de Hidalgo
    In this work the evaluation of an electrochemical reactor with stainless steel (A304) and titanium (Ti) electrodes was realized, applied in the silver recovery. The studies were performed at different flow velocities with empirical and dimensionless correlations, and parameters such as: current efficiency φe, energy consumption Es and space-time yield ρST. The results of the variation of the concentration of Ag at different flow linear velocities allowed the determination of the mass transfer coefficients of silver (order of 10-5) for A304 SS and Ti electrodes, which are consistent with the literature. The empirical and dimensionless correlations obtained pointed towards a fully developed turbulent flow. The current efficiency values above 100% indicated that the electrochemical process is coupled to an electroless process. The results showed low energy consumption Es and high φe and ρST values indicating that the reactor presents an excellent performance in the recovery of silver.

D-7: Preparation of Core-shell Fe3O4@SiO2 Nanoparticles from Iron Tailing via Chemical Co-precipitation Method: Chao Lv1; Shuming Wen1; Kun Yang1; Shaojun Bai1; 1Kunming University of Science and Technology
    In this study, iron was extracted from an iron tailing by phosphoric acid for synthesizing a high-value magnetic Fe3O4 nano-powder product by chemical co-precipitation. Furthermore, the Fe3O4 nano-powder was modified by coating with SiO2, the core-shell Fe3O4@SiO2 nanoparticles would have a big potential in water decontamination, biological science and medical technology. Under the optimum leaching condition, iron leaching efficiency could reach 81.55%. The synthetic Fe3O4 NPs with a high purity (Total Fe 72.04 %). Fe3O4 and Fe3O4@SiO2 particles were characterized by X-ray diffraction (XRD), Transmission Electron Microscope (TEM), Fourier transform infrared spectroscopy (FT-IR) and magnetic analysis. The results showed that the synthesized Fe3O4 NPs had a high level of crystallinity with an average diameter of about 10nm and Fe3O4@SiO2 NPs exhibited better dispersion and uniform spherical morphology with about 20nm diameter. Therefore, a new way was proposed for utilization of the iron tailings.

D-8: Recycling of Worn Lithium Ion Batteries through a Process of Co-grinding with PVC: Luz Ocampo Carmona1; Juan Betancur Pulgarin1; Juan Sanchez Echeverri1; 1Universidad Nacional de Colombia
    Li-ion used batteries were used, which were discharged by immersion in NaCl solution 5% w / w, subsequently subjected to a comminution process with its respective granulometric and compositional analysis by fluorescence X-rays to identify the it cobalt content on each sieve, then a co-grinding with PVC was performed in a ball mill high energy to times of 1, 2, and 3 hours to generate a reaction between chlorine of PVC and metals present in the waste batteries to form metal chlorides. Dilution of metal chlorides was then performed in water for producing metal ions available in an aqueous medium, which were analyzed by atomic absorption spectrophotometry. Cyclic voltammetry parallel tests were conducted to determine the potential values ​​to which the electrodeposition of metals occurs. By increasing the co-grinding time increased the amount of the obtained metal chlorides.

D-9: Chemical Reduction of Fe(III) in Nickel Lateritic Wastewater to Recover Metals by Ion Exchange: Amilton Botelho Junior1; Monica Jimenez1; Denise Espinosa1; Jorge Tenório1; 1University of São Paulo
    Wastewater from nickel lateritic process still has values metals that could be recover. Using ion exchange method to separate selective metals, the main problem is the iron precipitation, whereupon reduce the resin efficient. The goal of this research was to make iron soluble by reducing Fe+3 to Fe+2. Reducing agents sodium dithionite and sodium metabisulfite were used and the potential was verified using as a reference the iron’s Pourbaix diagram. The pH was ranging between 0,5 to 2, the reducing agent’s concentration was ranging between 0,5 to 2M, the reaction time was ranging between 30 to 420min and the temperature was ranging between 25 to 60⁰C. The results show the ideal point of reduction Fe+3 to increase the resin efficiency. Thereby, the batch process of ion exchange using these parameters was studied and temperature influence were also studied, which presented higher efficiency than before.