Abstract:
Platinum group metals (PGMs) assume an important role within the chemistry and chemical
engineering due to their exceptional chemical stability in high temperatures and various environmental conditions. Their unique attributes make them highly demanded materials across an
array of industries. Nevertheless, the gradual depletion of PGM reserves underscores necessitates
of recycling PGM-containing waste as a means to ensure the reasonable utilization of resources.
Recycling of catalytic waste, in particular, presents a more cost-effective and environmentally
sustainable approach acquiring these metals, in contrast to the conventional practice of mining
from natural ores. Of particular importance are spent automotive catalysts, which represent a
valuable source of platinum group metals, featuring substantially higher PGM concentrations
than their naturally occurring counterparts. Conventionally, the recovering of PGMs from waste
materials predominantly employs hydrometallurgical and pyrometallurgical processes. Unfortunately, these established techniques entail the utilization of potent oxidizing acidic solutions,
including aqua regia and hydrochloric acid with chlorine gas, which exert adverse ecological
consequences. In recent years, there has been a growing focus on the development of alternative
methodologies that are both environmentally friendly and economically viable for the recovery of
PGMs from spent catalysts. Notable among these emerging techniques are solvometallurgy, molecular recognition technology, and magnetic separation. This comprehensive review endeavors
to study and assess the latest advancements in the recovery of platinum group metals from spent
catalysts, meticulously evaluating their respective advantages and disadvantages. Through an
analysis, this review aspires to identify the most promising method - one that combines environmental friendliness and economic feasibility.
