Zero valent iron from iron wastes for environmental applications

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1 XVIII CYPRUS2016 ENCONTRO LUSO GALEGO DE QUÍMICA Vila Limassol Real, Portugal,,Cyprus, November, June, Zero valent iron from iron wastes for environmental applications Daniela V. Lopes, Rui C. Martins, Rosa M. Quinta Ferreira, Jorge R. Frade, Margarida J. Quina CIEPQPF Chemical Processes and Forest Products Research Center CICECO Centro de Investigação em Materiais Cerâmicos e Compósitos Chemical Engineering Department, University of Coimbra, Portugal

2 1. Introduction Metallurgical industries Chemical industries Mining industries Iron wastes production Consumption of natural resources Landfill disposal Recovery and valorisation!!! end of waste status Directive 2008/98/EC, 19 th November of

pollutants contaminant degradation chlorinated organic compounds; organochlorine

3 1. Introduction Zero valent Iron (ZVI) Fe 0 Reductive proprieties Fe 0 Fe 2+ +2e E 0 = 0,440 V Environmental remediation soil groundwater Environmental applications: Reduces pollutants contaminant degradation chlorinated organic compounds; organochlorine pesticides (PCBs); organic dyes; metal ions (As(III), Pb(II), Cu (II), Ni(II) and Cr(VI)); 3

4 1. Introduction Objective of the study Main goal: Use of iron wastes for the degradation of methyl orange 4

5 2. Experimental methodology 1) Screening of wastes: Iron Fenton Sludge (IFS) Cast Iron Shot (CIS) Grind Precipitate Dust (GPD) Iron Shavings (ISH) Fenton s Process Metallurgical industry Carpentry workshops 5

6 2. Experimental methodology 2) Chemical characterization of solid wastes: Solid wastes digestion Aqua regia (FAAS with Perkin Elmer 3300) Elemental analysis (Fisons EA1108) Surface area with BET (Micromeritics ASAP 2000) Mineralogic characterization (XRD) 6

7 2. Experimental methodology 3) Chemical reduction of iron from Iron Fenton Sludges (IFS): 200 rpm Mechanical stirrer Chemical reduction of Fe 3+ to Fe ml/min Peristaltic bomb It was not successful NaBH 4 ( 11 g/l) Extracted iron (Fe 3+ ) ( 3 g of extracted iron in 5 M of HCl for 2 h) 7

2. Experimental methodology 4) Treatment procedure for color removal of Methyl Orange (MO) + Fe 0 50 300 mg/l of MO ph tested: 5 10 GPD waste was

8 2. Experimental methodology 4) Treatment procedure for color removal of Methyl Orange (MO) + Fe mg/l of MO ph tested: 5 10 GPD waste was used in a range of 0.2 to 1 g/l C Water bath shaker, 100 rpm Color was measured at 465 nm with UV/vis spectroscopy after 90 min of reaction 8

2. Experimental methodology 5) Color removal

experiments Response variable: Factor Units 1 0

9 2. Experimental methodology 5) Color removal with DOE Design of Experiments (DOE): STATISTICA V9 Factors analyzed: Box Behnken (response surface methodology at 3 levels) 30 experiments Response variable: Factor Units MO mg/l ph ZVI g/l T C

3. Results and discussion Solid wastes characterization Wastes rejected! IFS CIS GPD ISH Moisture (%) 52.3±0.7 0.1±0.01 0.6±0.01 0 VS (%) 52.8±0.1 1.3±0.4 0 0 Fe (g/kg) 302.0±17.5 0 447.7±24.

10 3. Results and discussion Solid wastes characterization Wastes rejected! IFS CIS GPD ISH Moisture (%) 52.3± ± ± VS (%) 52.8± ± Fe (g/kg) 302.0± ± A BET (m 2 /g) 0.58± ± ±0.04 Density (kg/m 3 ) 1717± ±34 D p 26µm <0,1mm <0,1mm <0,5mm N(%) C(%) H(%) S(%)

11 3. Results and discussion Solid wastes characterization XRD Solid wastes characterization Cast Iron Shot (CIS) Grind Precipitate Dust (GPD) SiO 2 SiO 2 Al Fe Fe 3 O 4 Fe Fenton sludge (IFS) Fe 2 O 3 or FeO(OH) Fe Iron Shavings (ISH) Intensity (CPS) Fe 11 Two Teta (deg)

of ZVI wastes (GPD ans ISH) were tested; 2 ml of HCl; Fe 0 present in the

12 3. Results and discussion Fe 0 quantification present in the wastes for MO degradation Fe 0 (s) + HCl (aq) FeCl 2 (aq) + H 2 (g) 50 ml eudiometer; 50 mg of ZVI wastes (GPD ans ISH) were tested; 2 ml of HCl; Fe 0 present in the wastes GPD: 90.3% of Fe 0 and 9.8% of oxides/sio 2 ISH: 60% of Fe 0 and 40% of oxides 12

3. Results and discussion Design of Experiments R 2 = 0,73017 Factors analyzed: Factor SS df MS F p 153,734 2

620,329 2 310,165 4,500 0,033 13,262 1 13,262 0,192 0,668 Response variable: 48,580 1 48,580 0,705 0,416 21,878 1

13 3. Results and discussion Design of Experiments R 2 = 0,73017 Factors analyzed: Factor SS df MS F p 153, ,867 1,115 0,357 21, ,963 0,159 0, , ,088 7,764 0, , ,831 1,840 0, , ,165 4,500 0,033 13, ,262 0,192 0,668 Response variable: 48, ,580 0,705 0,416 21, ,878 0,317 0,582 46, ,603 0,676 0,426 15, ,249 0,221 0,646 4, ,162 0,060 0,810 Error 895, ,

14 3. Results and discussion Design of Experiments Color removal (%) RemMO 20 (%) > 60 < 60 < 56 < 52 < 48 < ph MO > 52 < 52 < 48 < 44 < 40 < RemMO 20 (%) 1, ,9 0, , ,6 0,5 ZVI MO ,4 0, ,2 ph vs MO i (mg/l) ZVI (g/l) vs MO i (mg/l) Acidic ph are better for color removal Higher loads of ZVI lead to higer efficiencies of color removal to relatively lower MO (mg/l)

15 100 ults and discussion ign of Experiments Color removal (%) > 44 < 44 < 40 < 36 < T MO T vs MO i (mg/l) > 60 < 60 < 40 ph 0,5 0, ,3 0,2 ZVI (g/l) vs ph 0,6 0,8 0,7 ZVI 0, ,0 RemMO (%)

16 38 ults and discussion ign of Experiments Color removal (%) T ph > 60 < 52 < T vs ph > 48 < 48 < 44 < 40 < 36 < 32 < ,0 0,9 0,8 0,7 0,6 ZVI 0,5 24 0,4 22 0,3 20 0,2 T vs ZVI (mg/l) 32 T RemMO 6

17 ults and discussion ign of Experiments Color removal (%) imal solution in the model with GPD: O(mg/L) 50 ph 5 ZVI (g/l) 1 T ( C) 32.6 r Removal (%) 72.3 Validation of the optimal solution in the model with GPD: 64.2±1.2% (Error: 8.1%) of iron shavings for the optimal solution: 59.4±0.4%

18 clusions and forthcoming work onclusions mical reduction of Fe 3+ from wastes seems to be challenging by sodim borohydride roach; d Precipitate Dust (GPD) and Iron Shavings (ISH) wastes can be used as ZVI in ironmental reactions; approach revealed to be relevant in order to compare the interactions of variables e model and to optimize the model ( acidic ph is the most relevant factor in order to ove MO); und 60% of efficiency on the color removal of MO was attained with both wastes. rthcoming work

19 Daniela Lopes Acknowledgements: PD/BD/114106/2015 IF/00215/2014

Optimization of ZVI Technology for In-Situ Remediation of Chlorinated Contaminants. Dr. John Freim OnMaterials, LLC Escondido, CA

Optimization of ZVI Technology for In-Situ Remediation of Chlorinated Contaminants. Dr. John Freim OnMaterials, LLC Escondido, CA Dr. John Freim OnMaterials, LLC Escondido, CA Chlorinated Solvent Contamination - Background Dry cleaners PCE used as cleaning agent Many dry cleaning facilities had leaks, spills, improper disposal Former