Paper Title
Enrichment of Noble Metals and Rare Earth Elements from Contaminated Biomass Before Extraction

Abstract
In this era of industrialization and metal reserve depletion, recovering noble metals (NMs) and rare earth elements (REEs) from secondary resources is essential which assists to strengthen the circular economy. Contaminated biomass growing from brownfield lands is a potential material for metal recovery. However, before the extraction process, the bulky contaminated biomass needs to be lessened to a manageable volume and amount. This study investigates the combustion process of biomass containing NMs, REEs, and the behavior of these metals in the burning system. Contaminated biomass gathered from an abandoned mining area was combusted in a pilot-scale boiler, while solid residuals from different positions in the burning system were collected and analyzed. Higher concentrations of NMs and REEs in the ash samples compared to that in the woody biomass indicate the efficiency of the combustion process from the metal enrichment perspective. The significant metal concentration in the ashes is an advantage for the following step of extraction to reclaim NMs and REEs. The results also show the low volatility of REEs, while NMs are highly volatilized during biomass incineration. Keywords - Polluted Biomass, Biomass Combustion, Precious Metals, Rare Earth Metals