Bio-removal of rare earth elements from hazardous industrial waste of CFL bulbs by the extremophile red alga Galdieria sulphuraria

Abstract

In recent decades, a shift has been seen in the use of light-emitting diodes over incandescent lights and compact fluorescent lamps (CFL), which eventually led to an increase in wastes of electrical equipment (WEE), especially fluorescent lamps (FLs) and CFL light bulbs. These widely used CFL lights, and their wastes are good sources of rare earth elements (REEs), which are desirable in almost every modern technology. Increased demand for REEs and their irregular supply have exerted pressure on us to seek alternative sources that may fulfill this demand in an eco-friendly manner. Bio-removal of wastes containing REEs, and their recycling may be a solution to this problem and could balance environmental and economic benefits. To address this problem, the current study focuses on the use of the extremophilic red alga, Galdieria sulphuraria, for bioaccumulation/removal of REEs from hazardous industrial wastes of CFL bulbs and the physiological response of a synchronized culture of G. sulphuraria. A CFL acid extract significantly affected growth, photosynthetic pigments, quantum yield, and cell cycle progression of this alga. A synchronous culture was able to efficiently accumulate REEs from a CFL acid extract and efficiency was increased by including two phytohormones, i.e., 6-Benzylaminopurine (BAP - Cytokinin family) and 1-Naphthaleneacetic acid (NAA - Auxin family).

Settling selection of Chlamydomonas reinhardtii for samarium uptake

“…Likewise, the effective photochemical quantum yield (F v /F m ) of the Y(II) was inhibited by Sm in the control, CSm0, and CSmm4. Similar growth and stress effects have been observed in other microalgae species exposed to Sm and other lanthanides (Singh et al, 2023;Tai et al, 2010). This could be related to calcium pathways as previously demonstrated in lanthanides with other microalgae (Goecke et al, 2015 We observed how the Y(II) was reduced for each strain in the presence of Sm.…”

Multi-Endpoint Analysis of Cerium and Gadolinium Effects after Long-Term Exposure to Phaeodactylum tricornutum

“…REE tolerance mechanisms have been reported in plants such as Dicranopteris linearis, Phytolacca sp., Helianthus Annuus [32][33][34], and in microalgae such as Galdieria sulphuraria and Desmodesmus quadricauda [35,36], but very little information concerns diatoms [26].…”

Microbial recovery of rare earth elements from various waste sources: a mini review with emphasis on microalgae

“…they were not only adsorbed onto the cell wall. G. sulphuraria accumulated significant levels of Ce, Nd, La and Y from red mud, a byproduct of alumina production (Náhlík et al 2023 ), and REEs from waste luminophores (Singh et al 2023 ). Another red alga Galdieria phlegrea was used to test bioaccumulation of REEs from luminophores from fluorescence lamps and energy saving light bulbs added into the medium in the form of a powder.…”

“…Synechococcus elongatus Calothrix brevissima Desmonostoc muscorum Komarekiella Biosorption Biosorption Biosorption Biosorption Biosorption Batch, 23 °CC, 37 °CC, pH8, 300 µmol/s/m 2 batch, 23 °CC, 37 °CC, pH8, 300 µmol/s/m 2 batch, 23 °CC, 37 °CC, pH8, 300 µmol/s/m 2 batch, 23 °CC, 37 °CC, pH8, 300 µmol/s/m 2 batch, 23 °CC, 37 °CC, pH8, 300 µmol/s/m 2 Paper et al ( 2023 ) Eu, Sm, Nd Anabaena sp . Anabaena cylindrica Biosorption Biosorption batch, 12d, 22 °CC, pH6.8 batch, 12d, 22 °CC, pH6.8 Fischer et al ( 2019 ) REEs from luminophores Galdieria sulphuraria Galdieria phlegrea Bioaccumulation Bioaccumulation batch, 1d, 40 °CC, pH3, 350 µmol/s/m 2 batch, 5d, 39 °CC, pH4, 150 µmol/s/m 2 Singh et al ( 2023 ) Čížková et al ( 2021 ) REEs from red mud Galdieria sulphuraria Phormidium sp. Oscillatoria sp.…”