2301
Sustainable Valorization of Phosphate Waste Rock: Ecofriendly
Phosphate Recovery Using Novel Flotation Biobased Reagents
Asmae El-Bahi, Yassine Taha, Yassine Ait-Khouia, Mostafa Benzaazoua
Geology &Sustainable Mining Institute (GSMI), Mohammed VI Polytechnic University, Ben Guerir, Morocco
ABSTRACT: Phosphate ore is crucial for fertilizer and chemical production but leads to substantial waste and
environmental impact. To address sustainability concerns, eco-friendly solutions are sought. This study aims
to recover phosphate from waste using biobased reagents in flotation. These renewable reagents can mitigate
ecological effects associated with conventional chemicals. Through fundamental studies and batch flotation tests,
the reagents’ adsorption behavior and performance are evaluated. Automated mineralogical characterization
enhances understanding of mineral separation efficiency. Results indicate the potential applicability of these
biobased reagents in phosphate waste rock valorization, offering a promising pathway towards a more sustainable
and environmentally friendly mineral processing approach.
Keywords: Phosphate waste rock, biobased reagents, sustainability, circular economy
INTRODUCTION
Phosphate is a strategic resource that has significant impli-
cations for global agriculture as part of a variety of other
industrial processes. It is crucial in the production of fer-
tilizers that are critical for promoting agricultural growth
and ensuring food security (El Bamiki et al., 2021). Its
extraction requires the execution of a succession of complex
mining procedures, which inevitably generate substantial
quantities of waste materials. These materials exhibit a het-
erogeneous composition, consisting of a variety of miner-
als that, in spite of their considerable content of apatite,
have conventionally been neglected and stored in the form
of phosphate mine waste rock piles (Amar et al., 2023). A
number of studies focused on the characterization and the
exploration of the different valorization pathways of these
waste materials. They revealed that these waste materials
are mainly composed of different types of rocks including
indurated phosphate, flintstone, phosphated flint, silicious
marls, dolomitic limestone, silexite, tender marls, and some
clays. Numerous applications were proposed as prospective
methods to valorize these waste materials (Mabroum et al.,
2020). They have the potential to be effectively employed
in road construction materials, substitute binders, alterna-
tive aggregates for concrete, and as raw materials for phos-
phate recovery (A El Machi et al., 2021). This last path of
valorization can be achieved through a variety of processes,
such as leaching, calcination, gravity separation and flota-
tion (Aiman El Machi et al., 2021 el Mahdi Safhi et al.,
2022). Flotation has long been used to separate phosphate
minerals. To achieve a successful separation, this technique
requires introducing some flotation additives comprising
collectors to hydrophobize the surface of a specific fraction
of the ore and depressants to hydrophilize the other frac-
tion (Derhy et al., 2022). Petroleum based collectors are the
most used ones, but due to their non-biodegradability and
lack of sustainability many research studies were conducted
Sustainable Valorization of Phosphate Waste Rock: Ecofriendly
Phosphate Recovery Using Novel Flotation Biobased Reagents
Asmae El-Bahi, Yassine Taha, Yassine Ait-Khouia, Mostafa Benzaazoua
Geology &Sustainable Mining Institute (GSMI), Mohammed VI Polytechnic University, Ben Guerir, Morocco
ABSTRACT: Phosphate ore is crucial for fertilizer and chemical production but leads to substantial waste and
environmental impact. To address sustainability concerns, eco-friendly solutions are sought. This study aims
to recover phosphate from waste using biobased reagents in flotation. These renewable reagents can mitigate
ecological effects associated with conventional chemicals. Through fundamental studies and batch flotation tests,
the reagents’ adsorption behavior and performance are evaluated. Automated mineralogical characterization
enhances understanding of mineral separation efficiency. Results indicate the potential applicability of these
biobased reagents in phosphate waste rock valorization, offering a promising pathway towards a more sustainable
and environmentally friendly mineral processing approach.
Keywords: Phosphate waste rock, biobased reagents, sustainability, circular economy
INTRODUCTION
Phosphate is a strategic resource that has significant impli-
cations for global agriculture as part of a variety of other
industrial processes. It is crucial in the production of fer-
tilizers that are critical for promoting agricultural growth
and ensuring food security (El Bamiki et al., 2021). Its
extraction requires the execution of a succession of complex
mining procedures, which inevitably generate substantial
quantities of waste materials. These materials exhibit a het-
erogeneous composition, consisting of a variety of miner-
als that, in spite of their considerable content of apatite,
have conventionally been neglected and stored in the form
of phosphate mine waste rock piles (Amar et al., 2023). A
number of studies focused on the characterization and the
exploration of the different valorization pathways of these
waste materials. They revealed that these waste materials
are mainly composed of different types of rocks including
indurated phosphate, flintstone, phosphated flint, silicious
marls, dolomitic limestone, silexite, tender marls, and some
clays. Numerous applications were proposed as prospective
methods to valorize these waste materials (Mabroum et al.,
2020). They have the potential to be effectively employed
in road construction materials, substitute binders, alterna-
tive aggregates for concrete, and as raw materials for phos-
phate recovery (A El Machi et al., 2021). This last path of
valorization can be achieved through a variety of processes,
such as leaching, calcination, gravity separation and flota-
tion (Aiman El Machi et al., 2021 el Mahdi Safhi et al.,
2022). Flotation has long been used to separate phosphate
minerals. To achieve a successful separation, this technique
requires introducing some flotation additives comprising
collectors to hydrophobize the surface of a specific fraction
of the ore and depressants to hydrophilize the other frac-
tion (Derhy et al., 2022). Petroleum based collectors are the
most used ones, but due to their non-biodegradability and
lack of sustainability many research studies were conducted