Bioleaching of Typical Electronic Waste—Printed Circuit Boards (WPCBs): A Short Review

Abstract

The rapid pace of innovations and the frequency of replacement of electrical and electronic equipment has made waste printed circuit boards (WPCB) one of the fastest growing waste streams. The frequency of replacement of equipment can be caused by a limited time of proper functioning and increasing malfunctions. Resource utilization of WPCBs have become some of the most profitable companies in the recycling industry. To facilitate WPCB recycling, several advanced technologies such as pyrometallurgy, hydrometallurgy and biometallurgy have been developed. Bioleaching uses naturally occurring microorganisms and their metabolic products to recover valuable metals, which is a promising technology due to its cost-effectiveness, environmental friendliness, and sustainability. However, there is sparse comprehensive research on WPCB bioleaching. Therefore, in this work, a short review was conducted from the perspective of potential microorganisms, bioleaching mechanisms and parameter optimization. Perspectives on future research directions are also discussed.

The reuse of electronic components from waste printed circuit boards: a critical review

“…19 WPCBs are then divided into bare boards and ECs for the deep processing step. 20 In the deep treatment stage, researchers have developed mechanical, 21 pyrogenic, 22 pyrolysis, 23 wet, [24][25][26] bioleaching, [27][28][29] and many other methods for resource recovery of WPCBs. For example, Wang et al 30 proposed a process to recover copper from PCBs by froth otation and oxidative leaching to increase the copper grade from 38.70% to 68.34%.…”

Metal Recycling via Biohydrometallurgy

“…Ein wichtiger Bestandteil von Elektronikschrott sind Leiterplatten (PCBs), die etwa 3-6 % des Gesamtgewichts des Elektronikschrotts und den gro ¨ßten Anteil an hochwertigen Metallen (z. B. Pt, Au, Ag, Cu, W, Co, Ge, Ga, In) ausmachen [60]. Die Biolaugung bietet hier gegenu ¨ber den bisherigen konventionellen Methoden eine potenziell nachhaltigere Alternative [58].…”

In situ high-valued transformation of nonmetals in waste printed circuit boards into supercapacitor electrodes with excellent performance

“…1 According to the statistics, the global quantity of electronic waste had reached approximately 57 Mt in 2021. 2 It is predicted that the annual growth rate of electronic waste will reach up to 2 Mt, which could lead to a total mass of 74.7 Mt accumulated by the year 2030. 3,4 Electronic waste not only contains toxic substances 5 but also contains a signicant number of valuable metals.…”