Depollution of mining effluents: innovative mobilization of plant resources

Abstract

Based on the ability of some specific aquatic plants to concentrate metals in their roots, we propose an innovative biosorption system to clean up mining effluents. The system we propose represents an interesting solution to an important environmental problem, the decontamination of metal-polluted water and prevention of dispersal of metals into the environment. The solution presented is a form of ecological recycling of Zn, an essential primary metal in many industrial applications. Finally, the methodology developed is a sustainable way of managing the biomass from eradication or control of invasive plants.

Closing the loop in a constructed wetland for the improvement of metal removal: the use of Phragmites australis biomass harvested from the system as biosorbent

“…As for the comparison with previously published biosorption data, most of the biomaterials reported in literature for metal removal with column systems are based on agricultural wastes recycled from the food production chain (e.g., Pérez Marín et al 2009 ; Iqbal et al 2013 ; Chao et al 2014 ; Abdolali et al 2017 ; Dong and Lin 2017 ). A fewer number of studies took into consideration plant biomass (Karunasagar et al 2005 ; Stanovych et al 2019 ), and, to the best of our knowledge, only one paper tested P. australis dried biomass in column mode for the removal of Cr(VI) (Lagiopoulos et al 2017 ). The comparison of the results obtained here with those previously reported in the literature is complicated by the fact that the metal removal efficiencies, in addition to the type of biosorbent (often chemically modified prior its use as biosorbent), are strongly affected by a number of operating parameters such as the percolation rate and the metal concentration of the influent solution (Abdolali et al 2017 ).…”

I - Ecologically responsible and efficient recycling of Pd from aqueous effluents using biosorption on biomass feedstock

“…It is well known that E. crassipes roots are rich in hemicellulose (Ruan et al, 2016) and thus in carboxylate functions. Recently, we have proven by mathematical fitting of FTIR-ATR assessments that roots of many aquatic plants (M. aquatica, E. crassipes, P. stratiotes, and L. peploides) are rich in carboxylate functions (Stanovych et al, 2019). The natural affinity of carboxylate moieties for transition metallic elements is consistent with functional features of aquatic plants and the biosorption performances of their roots.…”

“…So it was fair to assume that precipitation of the metallic species would prevent efficient adsorption on the biomaterials. ii) Nonetheless, we have recently shown that materials based on roots of aquatic plants are rich in carboxylate functions (Stanovych et al, 2019;De Laet et al, 2019). This fact could make roots of our group 4 plants more suitable than the biosorbents of other groups for the biosorption of Pd, owing to their stronger affinity for transition metals based on the formation of metal carboxylate salts.…”

“…Previously, we demonstrated that E. crassipes roots are rich in carboxylate functions. It seemed interesting to test for correlations between biosorption performances and the abundance of carboxylate functions (Stanovych et al, 2019;De Laet et al, 2019). Consequently, we investigated different materials derived from plant feedstocks.…”

“…Moreover, controlling the reproducibility of rhizofiltration parameters with living plants is challenging and seems incompatible with feasibility for industrial applications. Recently, we established that Zn phytoaccumulation by rhizofiltration is a passive non metabolically-mediated process (Stanovych et al, 2019;Grison et al, 2018). This result suggests an opportunity to develop a more practical approach based on the direct use of dead aquatic plants through biosorption technology.…”