Validation of Bromide Leaching through Response Surface Methodology and Separation of Gold from Waste Printed Circuit Boards
The daily consumption of gold is increasing worldwide; however, its availability from conventional ores is reducing. Alternatively, the presence of gold in waste electrical and electronic equipment (WEEE) is nearly 100 times higher than in natural ore. Therefore, the possibility of the recovery and...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-04-01
|
| Series: | Minerals |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2075-163X/13/4/579 |
| _version_ | 1797604160385843200 |
|---|---|
| author | Mudila Dhanunjaya Rao Pratima Meshram Abhilash Kamalesh K. Singh |
| author_facet | Mudila Dhanunjaya Rao Pratima Meshram Abhilash Kamalesh K. Singh |
| author_sort | Mudila Dhanunjaya Rao |
| collection | DOAJ |
| description | The daily consumption of gold is increasing worldwide; however, its availability from conventional ores is reducing. Alternatively, the presence of gold in waste electrical and electronic equipment (WEEE) is nearly 100 times higher than in natural ore. Therefore, the possibility of the recovery and separation of gold from waste printed circuit boards of obsolete mobile phones is studied in the present work. Initially, the optimization of parameters for the quantitative gold leaching from metal clads of PCBs with halide salts at acidic conditions is studied through response surface methodology. Three factors (parameters), viz. temperature, time and stirring speed are altered during the experiments based on the central composite design (CCD). Leaching parameters have been optimized with the help of the second-order empirical equations and analysis of variance (ANOVA) for maximum gold dissolution. The selective recovery and separation of gold from leach liquor have been achieved with solvent extraction with an organic amide as extractant followed by cementation with zinc powder. The separated gold powder has also been analyzed with XRD and SEM-EDS to check the purity and homogeneous elemental distribution. The statistical design of experiments and separation processes for the effective recovery of gold corroborates the economic feasibility of the proposed process. |
| first_indexed | 2024-03-11T04:42:27Z |
| format | Article |
| id | doaj.art-4b98c2c47fab4126bbf76adbd9a978c6 |
| institution | Directory Open Access Journal |
| issn | 2075-163X |
| language | English |
| last_indexed | 2024-03-11T04:42:27Z |
| publishDate | 2023-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Minerals |
| spelling | doaj.art-4b98c2c47fab4126bbf76adbd9a978c62023-11-17T20:36:40ZengMDPI AGMinerals2075-163X2023-04-0113457910.3390/min13040579Validation of Bromide Leaching through Response Surface Methodology and Separation of Gold from Waste Printed Circuit BoardsMudila Dhanunjaya Rao0Pratima Meshram1Abhilash2Kamalesh K. Singh3CSIR—National Metallurgical Laboratory, Jamshedpur 831007, IndiaCSIR—National Metallurgical Laboratory, Jamshedpur 831007, IndiaCSIR—National Metallurgical Laboratory, Jamshedpur 831007, IndiaDepartment of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, IndiaThe daily consumption of gold is increasing worldwide; however, its availability from conventional ores is reducing. Alternatively, the presence of gold in waste electrical and electronic equipment (WEEE) is nearly 100 times higher than in natural ore. Therefore, the possibility of the recovery and separation of gold from waste printed circuit boards of obsolete mobile phones is studied in the present work. Initially, the optimization of parameters for the quantitative gold leaching from metal clads of PCBs with halide salts at acidic conditions is studied through response surface methodology. Three factors (parameters), viz. temperature, time and stirring speed are altered during the experiments based on the central composite design (CCD). Leaching parameters have been optimized with the help of the second-order empirical equations and analysis of variance (ANOVA) for maximum gold dissolution. The selective recovery and separation of gold from leach liquor have been achieved with solvent extraction with an organic amide as extractant followed by cementation with zinc powder. The separated gold powder has also been analyzed with XRD and SEM-EDS to check the purity and homogeneous elemental distribution. The statistical design of experiments and separation processes for the effective recovery of gold corroborates the economic feasibility of the proposed process.https://www.mdpi.com/2075-163X/13/4/579goldresponse surface methodologyleachingwaste printed circuit boardscementation |
| spellingShingle | Mudila Dhanunjaya Rao Pratima Meshram Abhilash Kamalesh K. Singh Validation of Bromide Leaching through Response Surface Methodology and Separation of Gold from Waste Printed Circuit Boards Minerals gold response surface methodology leaching waste printed circuit boards cementation |
| title | Validation of Bromide Leaching through Response Surface Methodology and Separation of Gold from Waste Printed Circuit Boards |
| title_full | Validation of Bromide Leaching through Response Surface Methodology and Separation of Gold from Waste Printed Circuit Boards |
| title_fullStr | Validation of Bromide Leaching through Response Surface Methodology and Separation of Gold from Waste Printed Circuit Boards |
| title_full_unstemmed | Validation of Bromide Leaching through Response Surface Methodology and Separation of Gold from Waste Printed Circuit Boards |
| title_short | Validation of Bromide Leaching through Response Surface Methodology and Separation of Gold from Waste Printed Circuit Boards |
| title_sort | validation of bromide leaching through response surface methodology and separation of gold from waste printed circuit boards |
| topic | gold response surface methodology leaching waste printed circuit boards cementation |
| url | https://www.mdpi.com/2075-163X/13/4/579 |
| work_keys_str_mv | AT mudiladhanunjayarao validationofbromideleachingthroughresponsesurfacemethodologyandseparationofgoldfromwasteprintedcircuitboards AT pratimameshram validationofbromideleachingthroughresponsesurfacemethodologyandseparationofgoldfromwasteprintedcircuitboards AT abhilash validationofbromideleachingthroughresponsesurfacemethodologyandseparationofgoldfromwasteprintedcircuitboards AT kamaleshksingh validationofbromideleachingthroughresponsesurfacemethodologyandseparationofgoldfromwasteprintedcircuitboards |