TUNGSTEN RECOVERY AND ARSENIC REMOVAL FROM SECONDARY RESOURCES DEEP - PowerPoint PPT Presentation

28. June. 2019 J. Almeida 1 , R. Craveiro 2 , E.P. Mateus 1 , S. Barreiros 2 , A. Paiva 2 , A.B. Ribeiro 1 1 CENSE, Department of Sciences and Environmental Engineering 2 LAQV@Requimte, Department of Chemistry TUNGSTEN RECOVERY AND ARSENIC REMOVAL FROM SECONDARY RESOURCES DEEP EUTETIC SOLVENTS IN THE ELECTRODIALYTIC PROCESS Castro-Gomes, Mud collection at Panasqueira Mine, 2018

SCOPE Panasqueira Mine, Covilhã, PT Mining residues 2 J. Almeida @ Heraklion 2019

SCOPE Panasqueira Mine, Covilhã, PT Arsenic Mining residues 2 J. Almeida @ Heraklion 2019

SCOPE Panasqueira Mine, Covilhã, PT Arsenic Tungsten Mining residues 2 J. Almeida @ Heraklion 2019

SCOPE Panasqueira Mine, Covilhã, PT How to remove harmful compounds & recover critical raw materials from Arsenic secondary resources? Tungsten Mining residues 2 J. Almeida @ Heraklion 2019

SCOPE Panasqueira Mine, Covilhã, PT How to remove harmful compounds & recover critical raw materials from Arsenic secondary resources? Tungsten Electro-based Deep Eutetic Mining residues technologies Solvents 2 J. Almeida @ Heraklion 2019

SCOPE Panasqueira Mine, Covilhã, PT How to remove harmful compounds & recover critical raw materials from Arsenic secondary resources? Tungsten Electro-based Deep Eutetic Mining residues technologies Solvents Both techniques combined! 2 J. Almeida @ Heraklion 2019

SCOPE Panasqueira Mine, Covilhã, PT How to remove harmful compounds & recover critical raw materials from Arsenic secondary resources? Tungsten Electro-based Deep Eutetic Mining residues technologies Solvents Both techniques combined! Treated mining residues for reuse in the construction sector 2 J. Almeida @ Heraklion 2019

MATRIX CHARACTERIZATION ➔ Low conductivity 0.8 ± 0.4 mS/cm ➔ Acidic pH 5.3 ± 0.5 ➔ Arsenic content As: 1675 ± 564 mg/kg Castro-Gomes, Mud collection at Panasqueira Mine, 2018 ➔ Tungsten content Sample W: 130 ± 31 mg/kg Rejected fraction from sludge circuit (tube output; pumped directly to the ➔ Other elements of interest Panasqueira dam) Cu: 731 ± 270 mg/kg Sn: 38 ± 9 mg/kg 3 J. Almeida @ Heraklion 2019

MATRIX ELEMENTS X-Ray Fluorescence (XRF) Semi-Quantitative Data (%) 0.4% P, Cr, Mn, Se, Rb, Sr, Y, Zr, Nb, Cd, Sn, Ba, Pb W 13.4% 0.3% Al S, K, Ca, Ti, Fe, Cu, Zn, 18.6% As As, W 0.6% Si 67.6% XRF spectrometer 4 J. Almeida @ Heraklion 2019

DEEP EUTETIC SOLVENTS Acids, amides, amines and alcohols as liquid ≤ 100 °C Hydrogen bond donor Quaternary ammonium + Deep Eutetic Solvents = or metal salt (HDB) (DES) Ionic Liquids Deep Eutetic Solvents (natural products) X ✓ Low price Low toxicity X ✓ 100% atom X ✓ economy X ✓ Biodegradable ✓ ✓ Low vapor pressure ✓ ✓ Low volatility 5 J. Almeida @ Heraklion 2019

DEEP EUTETIC SOLVENTS Acids, amides, amines and alcohols as liquid ≤ 100 °C Hydrogen bond donor Quaternary ammonium + Deep Eutetic Solvents = or metal salt (HDB) (DES) Why DES? Ionic Liquids Deep Eutetic Solvents (natural products) X ✓ Low price Low toxicity X ✓ 100% atom X ✓ economy X ✓ Biodegradable ✓ ✓ Low vapor pressure ✓ ✓ Low volatility 5 J. Almeida @ Heraklion 2019

ELECTRO-BASED TREATMENT ➔ Electrokinetic (EK) and Electrodialytic (ED) treatments consist in a low current density (mA/cm 2 ) application between a pair of electrodes to promote removal/separation of substances, with an ionic exchange membrane interposed in the ED treatment (A) 3 compartments ED cell H + OH - (B) & (C) 2 compartments ED cell + - AEM – Anionic exchange membrane AEM CEM CEM – Cationic Exchange membrane (A) H + OH - + - - + OH - H + AEM CEM (C) (B) 6 J. Almeida @ Heraklion 2019

GOALS Arsenic Tungsten Mining residues (MR) 7 J. Almeida @ Heraklion 2019

GOALS Arsenic Tungsten Mining residues (MR) 7 J. Almeida @ Heraklion 2019

GOALS Arsenic Tungsten Mining residues (MR) 1 Selection of the most efficient DES for As and W extraction from the matrix 7 J. Almeida @ Heraklion 2019

GOALS Arsenic Tungsten Mining residues (MR) 1 Selection of the most efficient DES for As and W extraction from the matrix 2 Potential of the EK process combined with DES to improve As and W extraction from the matrix 7 J. Almeida @ Heraklion 2019

GOALS Arsenic Tungsten Mining residues (MR) 1 Selection of the most efficient DES for As and W extraction from the matrix 2 Potential of the EK process combined with DES to improve As and W extraction from the matrix 3 Feasibility of the ED process to separate As and W in a compartment apart from the matrix 7 J. Almeida @ Heraklion 2019 J. Almeida @ Heraklion 2019

METHODOLOGY 1 Selection of the most efficient DES for As and W extraction from the matrix ➔ ChCl:MA - Choline Chloride:Malonic Acid (1:2) ➔ ChCl:OA - Choline Chloride:Oxalic Acid (1:1) DES tested ➔ ChCl:LA - Choline Chloride:Latic Acid (1:2) ➔ PA:U - Propionic Acid:Urea (2:1) Liquid/solid = 9 Stirring 10 days DES + MR 8 J. Almeida @ Heraklion 2019

METHODOLOGY 2 Potential of the EK process combined with DES to improve As and W extraction from the matrix As ➔ ChCl:MA - Choline Chloride:Malonic Acid (1:2) DES tested with higher ➔ ChCl:OA - Choline Chloride:Oxalic Acid (1:1) W As and W extraction 50 & 100 mA + - mA - Liquid/Solid=9 + Stirring 4 days DES + MR +H 2 0 (1.5% ChCl:MA & 1.5% ChCl:OA) 9 J. Almeida @ Heraklion 2019

METHODOLOGY 3 Feasibility of the ED process to separate As and W in a compartment apart from the matrix As ➔ ChCl:MA - Choline Chloride:Malonic Acid (1:2) DES tested with higher ➔ ChCl:OA - Choline Chloride:Oxalic Acid (1:1) W As and W extraction 50 & 100 mA H + DES + MR +H 2 0 Liquid/Solid=9 + - (1.5% ChCl:MA & 1.5% ChCl:OA) OH - Electrolyte 0.01 M NaNO 3 AEM Stirring mA 4 days - + 10 J. Almeida @ Heraklion 2019

RESULTS & DISCUSSION 1 Selection of the most efficient DES for As and W extraction from the matrix Arsenic and Tungsten extraction As W 12% 12,1% 9% 8,6% 6,6% 6,5% 7% 7% 5% 5,0% 5% 4,8% 2% 2,4% 1,0% 1% ChCl:OA ChCl:LA ChCl:PA ChCl:MA ChCl:Acid malonic (1:2) ChCl: Oxalic Acid (1:1) ChCl: Latic Acid (1:2) Propionic Acid:urea (2:1) 11 J. Almeida @ Heraklion 2019

RESULTS & DISCUSSION 1 Selection of the most efficient DES for As and W extraction from the matrix Arsenic and Tungsten extraction As W 12% 12,1% 9% 8,6% 6,6% 6,5% 7% 7% 5% 5,0% 5% 4,8% 2% 2,4% 1,0% 1% ChCl:OA ChCl:LA ChCl:PA ChCl:MA ChCl:Acid malonic (1:2) ChCl: Oxalic Acid (1:1) ChCl: Latic Acid (1:2) Propionic Acid:urea (2:1) 11 J. Almeida @ Heraklion 2019

RESULTS & DISCUSSION 2 Potential of the EK process combined with DES to improve As and W extraction from the matrix Extraction percentages in relation to DES experiments without current As W + 21% + 10% + 7% + 6% + 3% + 0.4% 0% -2% -2% 50 mA – ChCl:OA 100 mA – ChCl:OA 50 mA– ChCl:MA 100 mA – ChCl:MA 12 J. Almeida @ Heraklion 2019

RESULTS & DISCUSSION 2 Potential of the EK process combined with DES to improve As and W extraction from the matrix Extraction percentages in relation to DES experiments without current As W + 21% + 10% + 7% + 6% + 3% + 0.4% 0% -2% -2% 50 mA – ChCl:OA 100 mA – ChCl:OA 50 mA– ChCl:MA 100 mA – ChCl:MA 12 J. Almeida @ Heraklion 2019

VOLTAGE, pH & CONDUCTIVITY CONTROL pH 15 10 Voltage pH 5 Voltage (V) 10 0 0 Conductivity 0 24 48 72 96 Time (hours) Conductivity (mS/cm) 50 mA - ChCl:OA 50 mA - ChCl:MA 5 100 mA - ChCl:OA 100 mA - ChCl:MA 0 0 24 48 72 96 Time (hours) 13 J. Almeida @ Heraklion 2019

RESULTS & DISCUSSION 3 Feasibility of the ED process to separate As and W in a compartment apart from the matrix Compartments distribution of As and W extracted contents 40% 30% 17% 20% 7% 21% 10% 18% 5% 15% 6% 1% 4% 5% 1% 6% 4% 4% 3% 2% 0% As W As W As W As W 50 mA - ChCl:OA 100 mA - ChCl:OA 50 mA - ChCl:MA 100 mA - ChCl:MA Sample compartment (Liquid phase) Electrolyte compartment 14 J. Almeida @ Heraklion 2019 Removed – Liquid phase + electrolyte contents; Separated – electrolyte content

RESULTS & DISCUSSION 3 Feasibility of the ED process to separate As and W in a compartment apart from the matrix Compartments distribution of As and W extracted contents 40% 30% Higher As separation 17% Higher W separation 20% 7% 21% 10% 18% 5% 15% 6% 1% 4% 5% 1% 6% 4% 4% 3% 2% 0% As W As W As W As W 50 mA - ChCl:OA 100 mA - ChCl:OA 50 mA - ChCl:MA 100 mA - ChCl:MA Sample compartment (Liquid phase) Electrolyte compartment 14 J. Almeida @ Heraklion 2019 Removed – Liquid phase + electrolyte contents; Separated – electrolyte content