@article{MTMT:34437318, title = {The fate of noble metals and rare earth elements during pelletized biomass combustion}, url = {https://m2.mtmt.hu/api/publication/34437318}, author = {Dinh Phi, Truong and Kovács, Helga and Dobó, Zsolt}, doi = {10.1016/j.heliyon.2023.e23546}, journal-iso = {HELIYON}, journal = {HELIYON}, volume = {10}, unique-id = {34437318}, abstract = {The extraction of rare earth elements (REEs) and noble metals (NMs) from unconventional resources is playing a crucial role under the context of industrialization and reserve depletions. Plants used for phytoextraction are promising materials for the recovery of metals, but the biomass needs to be reduced to a manageable amount and volume prior to the extraction process. This paper investigates the combustion process of biomass focusing on NMs and REEs flow. The plants harvested from a brownfield land were pelletized and incinerated in a fixed-grate pilot-scale boiler, meanwhile, solid remains from various points in the combustion and flue gas system were captured and analyzed. The results show that levels of NMs in deposited ash and fly ash are greater than in bottom ash. Meanwhile, the higher REE concentration in bottom ash compared to that in other solid residuals demonstrates the less ability of these compounds to escape from the combustion chamber. Generally, the concentrations of REEs and NMs in the solid residues are significantly higher compared to biomass. SEM-EDS analyses of the contaminated solid remains indicate that gold forms individual particles with purity higher than 95 wt% in the bottom ashes, and this finding adds novel insights into gold phytomining.}, keywords = {Rare earth elements; Precious metals; Biomass combustion}, year = {2024}, eissn = {2405-8440}, orcid-numbers = {Kovács, Helga/0000-0001-9189-2048} } @article{MTMT:34442884, title = {Experimental system for combustion of contaminated biomass}, url = {https://m2.mtmt.hu/api/publication/34442884}, author = {Dinh Phi, Truong and Dobó, Zsolt and Kovács, Helga}, journal-iso = {Doktorandusz Almanach}, journal = {Doktorandusz Almanach}, volume = {1}, unique-id = {34442884}, issn = {2939-7294}, year = {2023}, pages = {220-226}, orcid-numbers = {Kovács, Helga/0000-0001-9189-2048} } @article{MTMT:34062288, title = {Elemental Analysis of Contaminated Biomass Ashes for Phytomining of Rare Earth Elements}, url = {https://m2.mtmt.hu/api/publication/34062288}, author = {Dinh Phi, Truong and Dobó, Zsolt and Kovács, Helga}, doi = {10.14232/analecta.2023.3.26-32}, journal-iso = {REV FAC ENG ANALECTA TECH SZEGED}, journal = {ANALECTA TECHNICA SZEGEDINENSIA}, volume = {17}, unique-id = {34062288}, issn = {1788-6392}, abstract = {Phytomining of rare earth elements (REEs) provides a potential possibility for metal recovery at brownfields where conventional mining technique is not reasonable or profitable. The holistic concept of phytomining is instituted from three scientific sectors. Phytoextraction is the first stage referred to accumulation of REEs in plants. This is followed by the enrichment process aiming to elevate metal concentration into solid remains. Eventually, extraction technology is applied to reclaim these valuable metals from the bio-ores. The main goal of this study is to identify a possible location for REEs phytomining, which lays the groundwork for further investigations. To do that, different woody biomass from disparate contaminated spots was harvested and examined. A brownfield land located in Gyöngyösoroszi, Hungary has been selected based on the elemental analysis of ash samples obtained from the incineration of the collected plants at 500 °C. The outcomes also preliminarily indicate the viability of phytomining in recovering REEs.}, year = {2023}, eissn = {2064-7964}, pages = {26-32}, orcid-numbers = {Dinh Phi, Truong/0000-0003-3810-4764; Kovács, Helga/0000-0001-9189-2048} } @CONFERENCE{MTMT:33828370, title = {Enrichment of valuable metals from contaminated biomass into combustion solid remains}, url = {https://m2.mtmt.hu/api/publication/33828370}, author = {Dinh Phi, Truong and Dobó, Zsolt and Kovács, Helga}, booktitle = {11th European Combustion Meeting, ECM 2023}, unique-id = {33828370}, abstract = {Recovering valuable metals including noble metals (NMs) and rare earth elements (REEs) from unconventional resources is necessary under the context of metal reserve depletion. Contaminated plants coming from brownfields are a potential metal source. Nonetheless, the amount of these plants should be reduced and valuable metals in biomass should be concentrated before the extraction process. Combustion of contaminated biomass is a metal enrichment option that was investigated in this study. Polluted plants collected from a former mine were combusted in a pilot-scale boiler. While ashes captured from different points of the burning system were dissected to research the behavior of valuable metals. The outcomes show that NMs are highly volatile as their concentrations in bottom ash are lower than in other solid remains. The opposite trend was observed in the case of REEs indicating the minor volatility of these metal compounds during the combustion process. More importantly, the grades of valuable metals in combustion ashes are greater than that in the biomass sample demonstrating the effectiveness of the combustion process in heightening metal levels. High concentrations of valuable metals in solid remains are favorable for the subsequent extraction process to recover NMs and REEs.}, year = {2023}, pages = {1-5}, orcid-numbers = {Kovács, Helga/0000-0001-9189-2048} } @CONFERENCE{MTMT:33712109, title = {Enrichment of Noble Metals and Rare Earth Elements from Contaminated Biomass Before Extraction}, url = {https://m2.mtmt.hu/api/publication/33712109}, author = {Kovács, Helga and Dinh Phi, Truong and Dobó, Zsolt}, booktitle = {Proceedings of IASTEM International Conference 2022}, unique-id = {33712109}, 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.}, year = {2022}, pages = {13-16}, orcid-numbers = {Kovács, Helga/0000-0001-9189-2048} } @article{MTMT:33541153, title = {The overall concept of phytomining of noble metals}, url = {https://m2.mtmt.hu/api/publication/33541153}, author = {Dinh Phi, Truong and Dobó, Zsolt and Kovács, Helga}, journal-iso = {Doktorandusz Almanach}, journal = {Doktorandusz Almanach}, volume = {1}, unique-id = {33541153}, issn = {2939-7294}, year = {2022}, pages = {224-230}, orcid-numbers = {Kovács, Helga/0000-0001-9189-2048} } @inproceedings{MTMT:33354753, title = {The overall concept of phytomining of rare earth elements}, url = {https://m2.mtmt.hu/api/publication/33354753}, author = {Dinh Phi, Truong and Dobó, Zsolt and Kovács, Helga}, booktitle = {Fókuszban a hazai felszín alatti természeti erőforrások}, unique-id = {33354753}, year = {2022}, pages = {113-120}, orcid-numbers = {Kovács, Helga/0000-0001-9189-2048} } @book{MTMT:33322109, title = {Fókuszban a hazai felszín alatti természeti erőforrások. Nyersanyagok, energia és technológiák nexusa}, url = {https://m2.mtmt.hu/api/publication/33322109}, isbn = {9789633582770}, editor = {Kovács, Helga and Madarász, Tamás and Nagy, Gábor and Nagy, István and Szűcs, Péter and Németh, Norbert and Vadászi, Marianna}, publisher = {University of Miskolc}, unique-id = {33322109}, year = {2022}, orcid-numbers = {Kovács, Helga/0000-0001-9189-2048; Nagy, Gábor/0000-0003-3571-9122; Németh, Norbert/0000-0002-4264-5136} } @article{MTMT:33051536, title = {Enrichment of rare earth elements from contaminated biomass prior to extraction}, url = {https://m2.mtmt.hu/api/publication/33051536}, author = {Dinh Phi, Truong and Dobó, Zsolt and Kovács, Helga}, doi = {10.14232/analecta.2022.1.77-82}, journal-iso = {REV FAC ENG ANALECTA TECH SZEGED}, journal = {ANALECTA TECHNICA SZEGEDINENSIA}, volume = {16}, unique-id = {33051536}, issn = {1788-6392}, abstract = {Under the context of reserve depletion, recovering 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 REE recovery. However, prior to the extraction stage, polluted plants need to be lessened to a manageable volume. In this study, 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 REE concentration in the ash samples compared to that in the woody biomass indicates the efficiency of the combustion process from the metal enrichment point of view. The significant metal concentration in the solid remains is an advantage for the following step of extraction to reclaim REEs. It was concluded that the concentration of REEs in bottom ash is greater than in the other solid residuals. That indicates that the volatility of rare earth minerals is limited during biomass incineration.}, year = {2022}, eissn = {2064-7964}, pages = {77-82}, orcid-numbers = {Kovács, Helga/0000-0001-9189-2048} } @misc{MTMT:32759670, title = {Enrichment of Rare Earth Elements from Contaminated Biomass Prior to Extraction}, url = {https://m2.mtmt.hu/api/publication/32759670}, author = {Dinh Phi, Truong and Dobó, Zsolt and Kovács, Helga}, unique-id = {32759670}, year = {2022}, orcid-numbers = {Kovács, Helga/0000-0001-9189-2048} }