Platinum Recovery Techniques for a Circular Economy

Abstract

Platinum and other metals are very scarce materials widely used in the energy and transportation sector among other sectors. Obtaining Platinum is becoming more difficult due to its scarcity on earth and because of the high amount of energy and water used for its extraction. In this regard, the recycling of platinum is necessary for sustainable technologies and for reaching a circular economy towards this expensive and rare metal. Conventional methods for platinum recycling make use of enormous amounts of energy for its recovery, which makes them not very attractive for industry implementation. Furthermore, these processes generate very toxic liquid streams and gas wastes that must be further treated, which do not meet the green environmental point of view of platinum recycling. Consequently, new advanced technologies are arising aiming to reach very high platinum recovery rates while being environmentally friendly and making a huge reduction of energy use compared with the conventional methods. In this review, conventional platinum recovery methods are summarized showing their limitations. Furthermore, new and promising approaches for platinum recovery are reviewed to shed light on about new and greener ways for a platinum circular economy.

Electrolyzer and Fuel Cell Recycling for a Circular Hydrogen Economy

“…The most established recycling technologies focus on recovering valuable precious metals and are already applied at an industrial scale for platinum group metal (PGM) extraction from vehicle catalytic converters. [15] Hydrometallurgy leaches PGMs from the MEA Figure 1. Breakdown of the material components of proton exchange membrane water electrolyzers and fuel cells (PEMWE and PEMFC) and their applicable recycling pathways.…”

Recovery of catalytic metals from leaching solutions of spent automotive catalytic converters using plant extracts

“…However, some of those techniques may have drawbacks such as inadequate metal recovery (especially for low concentrations of metals), high energy requirements, as well as high chemical costs and environmental problems. This issue leaves open space for the emergence of new technologies aiming efficient PGM recovery with less operational costs and reduction in energy consumption while being environmentally friendly (Granados-Fernández et al 2021). As a result, metal biorecovery strategies, which make use of biological materials and/or processes, have attracted growing attention in recent years.…”

Highly selective adsorption of Pt(IV) from spent catalyst by polyethyleneimine functionalized polyethylene/polypropylene non‐woven fabric

“…Meanwhile, the global annual recovery of Pt only accounted for around 25% of the consumption in recent several years 4 . More importantly, the concentration of Pt in spent catalysts (higher than 2000 g t −1 in fuel cell) is usually hundreds of times that in natural ores (beneath 10 g t −1 ) 2 . Consequently, developing appropriate technique with high recovery efficiency will be of great significance for alleviating the shortage of Pt resources.…”

“…Platinum (Pt) has been widely used as catalyst in industrial fields including hydrogen energy production, automobile exhaust treatment, petrochemical, and electronic devices production owing to its excellent corrosion resistance, thermal stability, chemical inertness and catalytic performance. 1,2 Especially in the field of new energy vehicles, the number of fuel cell vehicles has sharply increased in recent years in terms of environmental protection, hereby enhancing the consumption amount of Pt catalyst. 3 However, the limited natural Pt resources mainly distributed in South Africa and Russia.…”