Acetic acid mediated leaching of metals from lead-free solders

Abstract

Background: The replacement of lead (Pb)-bearing solders by several Pb-free solders is a subject of intense research in these days due to the toxic effects of Pb on the environment. However, the Pb-free solders contain metals such as silver (Ag), copper (Cu), and zinc (Zn). The increasing use of these Pb-free solders again increases the risk of release of Ag, Cu, and Zn metals into the environment. The Pb-free solders can, therefore, be used as a secondary source for the metals which will not only help in environmental protection but also for the resource recovery. Results:This study reports a process to leach metals from hazardous soldering materials by acetic acid. Acetic acid was found more effective for metal recovery from the tin-copper (Sn-Cu) solder than tin-copper-silver (Sn-Cu-Ag) solder. Various process parameters were optimized for recovery of metals from Sn-Cu solder. It required 30 h for 100% recovery of Cu and Sn, respectively. The metal recovery increased gradually with an increase in acid concentration approaching complete recovery at an acid concentration of 80%. Effect of shaking speed and temperature on the recovery of metals from Sn-Cu solder was studied. The metal recovery decreased with an increase in solder weight. Conclusion:The present study reveals an effective process to recycle the Pb-free solders. The low concentration of acetic acid was also found significant for metal leaching from solder. The research provides basic knowledge for recovery of metals from Pb-free solders. which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Cost-effective and eco-friendly copper recovery from waste printed circuit boards using organic chemical leaching

“…Thus, from the previous literature each individual acid (especially inorganic acids) on leaching provides less amount of copper leaching whereas the leaching using organic acids recover moderate amount of Cu 2+ ions into the leaching medium. However the combination of these acids (our study) leached copper ions efficiently at higher concentration than other methods in the literature [ 10 , 12 , 23 ] which was represented in Fig. 7 .…”

“…Previous research on the chemical leaching of waste printed circuit boards using citric acid and H 2 O 2 found no significant difference in metal ion leaching due to temperature and shaking speed changes [ 10 ]. Previous research on the chemical leaching of waste printed circuit boards using citric acid and H 2 O 2 found no significant difference in metal ion leaching due to temperature and shaking speed changes [ 12 ].…”

“…It has been widely employed in a variety of industries, including manufacturing in the medical field, and the food industry. Acetic acid was discovered to be more effective for recovering metal from lead-free and tin-copper solders [ 12 ]. For the leaching of metals from used PCB, the combination of citric acid, acetic acid, and H 2 O 2 has not yet been tested.…”

A Supported Palladium Phosphide Catalyst for the Wacker‐Tsuji‐Oxidation of Styrene

“…Hence, the drop in activity may be accounted to the leaching of metal from the catalyst, leading to depletion of active species in the recovered catalyst. It is important to note at this point, that in system D acetic acid is used as solvent, which can cause leaching to occur [58,59] …”

“…It is important to note at this point, that in system D acetic acid is used as solvent, which can cause leaching to occur. [58,59]…”