Skip to Main content Skip to Navigation
Theses

Procédés innovants pour la valorisation du nickel directement extrait de plantes hyperaccumulatrices

Abstract : Agromining is a chain allowing the recovery of metals dispersed in soils or other matrices, using hyperaccumulator plants (HA). The first step is to grow these plants to achieve high yields of metals and the second to produce metal compounds of interest from the plant biomass. Agromining has mainly been developed to value nickel (Ni). Until now, biomass was burnt to concentrate the metal and remove organic matter. The challenge of this research is to design processes for Ni recovery by direct extraction from biomass, without burning the plant. It will allow a better understanding of the processes involved in the extraction of Ni from dry biomass using a solvent and the determination of the the speciation in the solution. Then, appropriate separation operations will be implemented to isolate the Ni in an interesting form for subsequent applications.Water leaching experiments, run at 20 ° C with two contrasted HAs, demonstrated that up to 80% of Ni could be transferred from the plant tissues to the solution. Ni is accompanied by major ions and organic compounds. The analysis of these compounds and the modeling of the chemical equilibria in solution showed that more than 95% of Ni was complexed by organic ligands, carboxylic acids (Ni carriers in the plant) as well as stronger complexing agents. From these results, separation processes were selected: selective precipitation and adsorption on complexing resin. They made it possible to recover respectively 75 and more than 95% of the nickel in sulphide or carboxylic compound forms. In contrast, purification with decanoate did not isolate the Ni.Thus, this work has made it possible to better understand the extraction of Ni directly from plants, the speciation of Ni in a multicomponent solution in the presence of organic ligands, and to valorize nickel by ways previously unexplored with this type of material
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-01976484
Contributor : Abes Star :  Contact
Submitted on : Thursday, January 10, 2019 - 9:56:07 AM
Last modification on : Friday, January 11, 2019 - 1:18:55 AM
Document(s) archivé(s) le : Thursday, April 11, 2019 - 2:12:40 PM

File

DDOC_T_2018_0179_GUILPAIN.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01976484, version 1

Collections

Citation

Mathilde Guilpain. Procédés innovants pour la valorisation du nickel directement extrait de plantes hyperaccumulatrices. Génie des procédés. Université de Lorraine, 2018. Français. ⟨NNT : 2018LORR0179⟩. ⟨tel-01976484⟩

Share

Metrics

Record views

218

Files downloads

519