Phytomining, the extraction of valuable metals from soil or waste substrates using plants, has gained increasing attention as a sustainable and economically viable alternative to conventional mining practices.

The use of living plants to recover precious metals with potential catalytic activity is still at the infant stage. In this study, selective hydrogenation of furfural to furfuryl alcohol using novel bio-ore catalysts recovered from the end stage of phytomining process is demonstrated. The phytomining process was carried out in the green house by artificially contaminating cassava (Manihot esculenta) plant with 500 mg/L palladium (Pd) and platinum (Pt) solutions for a period of eight weeks. After harvesting, concentrations of metals as high as 78 ± 0.047 and 1276 ± 0.036 µg/g of Pd and Pt, respectively, were detected in the calcinated root of cassava. The produced bio-ore catalysts; @PdCassCat and @PtCassCat were fully characterized with the following techniques: transmission electron microscopy (TEM), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), powder X-ray diffraction (pXRD), N₂-sorption, and UV-visible spectroscopy techniques and directly applied as catalysts for hydrogenation of furfural to furfuryl alcohol. The reaction was conducted under an optimized condition (furfural (10 mmol), triethylamine (Et₃N) (10 mmol), formic acid (20 mmol), temperature (160 °C), catalyst amount (40 mg)) realizing a yield of 76.5% and 100% furfuryl alcohol using @PdCassCat and @PtCassCat, respectively. The catalytic activities of the @PdCassCat and @PtCassCat were excellent as well as recyclable up to four and five times, respectively.

Mining is continuously an environmental worry to human sustainability most especially in developing nations. Phytomining an eco-friendly technique is a viable approach in that it offers benefits not only in the cleaning and rehabilitation of the mine wastes but recovery of the abandoned minerals in the tailings for economic benefits. While phytomining is not a substitute for conventional mining, it has the potential to function as a complementary technology for harnessing mineral resources that would otherwise remain unutilized. However, despite its promise, this technology remains underutilized in Africa, primarily because of the substantial financial requirements and complex innovations involved. This review therefore provides an in-depth evaluation of recent developments in the phytomining of precious metals across Africa, emphasizing regional advancements, existing challenges, and possible applications. In contrast to earlier studies, it takes a future-oriented assessment of phytomining by assessing the feasibility of phytomining while incorporating emerging technologies, economic considerations, and environmental implications. By consolidating recent findings, it presents fresh perspectives on enhancing phytoextraction techniques for sustainable metal extraction in the African context. The phytomining applications including the recovery of catalytically active bio-ores/nanoparticles from plants biomass were also summarized synthesizing Africa’s progress of bio-ore applications in catalysis.