Lisińska Magdalena, Wojtal Tomasz, Saternus Mariola, Willner Joanna, Rzelewska-Piekut Martyna, Nowacki Krzysztof
Zakłady Mechaniczne "WIROMET" S.A., ul. Wyzwolenia 27, 43-190 Mikołów, Poland.
Faculty of Materials Engineering, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice, Poland.
Materials (Basel). 2023 Dec 30;17(1):219. doi: 10.3390/ma17010219.
The paper presents the possibility of recovering metals from printed circuit boards (PCBs) of spent mobile phones using the hydrometallurgical method. Two-stage leaching of Cu(II), Fe(III), Sn(IV), Zn(II), Ni(II) and Pb(II) with HSO (2 and 5 M) and HNO (2 M) with the addition of HO (10 and 30%) and O (9 or 15 g/h) was conducted at various process conditions (temperature-313, 333 and 353 K, time-60, 120, 240, 300 min, type and concentration of leaching agent, type and concentration of oxidant, solid-liquid ratio (S/L)), allowing for a high or total metals leaching rate. The use of two leaching stages allows for the preservation of selectivity, separation and recovery of metals: in the first stage of Fe(III), Sn(IV) and in the second stage of the remaining tested metal ions, i.e., Cu(II), Zn(II), Ni(II) and Pb(II). Removing Fe from the tested PCBs' material at the beginning of the process eliminates the need to use magnetic methods, the purpose of which is to separate magnetic metal particles (ferrous) from non-magnetic (non-ferrous) particles; these procedures involve high operating costs. Since the leaching of Cu(II) ions with sulfuric(VI) acid practically does not occur (less than 1%), this allows for almost complete transfer of these ions into the solution in the second stage of leaching. Moreover, to speed up the process and not generate too many waste solutions, oxidants in the form of hydrogen peroxide and ozone were used. The best degree of leaching of all tested metal ions was obtained when 2 M sulfuric(VI) acid at 353 K was used in the 1st research stage, and 2 M nitric(V) acid and 9 g/h O at 298 K in the 2nd stage of leaching, which allowed it to be totally leached 100% of Fe(III), Cu(II), Sn(IV), Zn(II), Ni(II) and 90% Pb(II).
本文介绍了采用湿法冶金法从废旧手机印刷电路板（PCBs）中回收金属的可能性。在不同工艺条件（温度为313、333和353K，时间为60、120、240、300分钟，浸出剂类型和浓度、氧化剂类型和浓度、固液比（S/L））下，用HSO（2和5M）和HNO（2M）并添加HO（10%和30%）以及O（9或15g/h）对Cu(II)、Fe(III)、Sn(IV)、Zn(II)、Ni(II)和Pb(II)进行两阶段浸出，可实现较高或完全的金属浸出率。采用两阶段浸出可实现金属的选择性保留、分离和回收：第一阶段浸出Fe(III)、Sn(IV)，第二阶段浸出其余测试金属离子，即Cu(II)、Zn(II)、Ni(II)和Pb(II)。在工艺开始时从测试的印刷电路板材料中去除Fe，无需使用磁选方法，磁选的目的是将磁性金属颗粒（铁）与非磁性（有色金属）颗粒分离；这些程序涉及高昂的运营成本。由于用硫酸（VI）酸浸出Cu(II)离子实际上不会发生（小于1%），这使得这些离子在浸出的第二阶段几乎完全转移到溶液中。此外，为了加快工艺速度且不产生过多废液，则使用了过氧化氢和臭氧形式的氧化剂。在第一研究阶段使用353K的2M硫酸（VI）酸，在浸出的第二阶段使用298K的2M硝酸（V）酸和9g/h的O时，所有测试金属离子的浸出效果最佳，这使得100%的Fe(III)、Cu(II)、Sn(IV)、Zn(II)、Ni(II)以及90%的Pb(II)被完全浸出。
