BTEX removal from aqueous solution with hydrophobic Zr metal organic frameworks.

The Zr based metal organic framework, UiO-66, has been synthesized along with its isostructural equivalence tetrafluorinated, the UiO-66-F4. The corresponding ligands to these MOFs are the widely used BDC (1,4-benzenedicarboxylic acid) and the TFBDC (2,3,5,6-Tetrafluoro-1,4-benzenedicarboxylic acid). These coordination materials have been tested towards the sorption of the organic pollutants (Benzene, Toluene, Ethylbenzene and Xylene) in aqueous phase and both materials showed capacities to adsorb all the pollutants. It has been possible to compare the efficiency in the adsorption of two iso-structural MOFs, which will behave differently due to the hydrophobic behavior of the UiO-66-F4 MOF. The addition of F in the structure of the ligand of the MOF allows to obtain a hydrophobic material by changing the nature of the interactions between the adsorbent and the adsorbate from π-π stacking in the pristine UiO-66 to hydrophobic interactions in the UiO-66-F4. However, size of the pores has also revealed an important effect, since steric impediments will decrease the capacity of the fluorinated MOF towards the sorption of bigger molecules.

Recovery of metals from simulant spent lithium-ion battery as organophosphonate coordination polymers in aqueous media.

An innovative approach is proposed for the recycling of metals from a simulant lithium-ion battery (LIBs) waste aqueous solution. Phosphonate organic linkers are introduced as precipitating agents to selectively react with the metals to form coordination polymers from an aqueous solution containing Ni, Mn and Co in a hydrothermal process. The supernatant is analyzed by ICP-AES to quantify the efficiency and the selectivity of the precipitation and the materials are characterized by Scanning Electron Microscopy (SEM), Powder X-Ray Diffraction (PXRD), Thermogravimetric Analyses (TGA) and nitrogen gas sorption (BET). Conditions have been achieved to selectively precipitate Manganese or Manganese/Cobalt from this solution with a high efficiency. This work describes a novel method to obtain potentially valuable coordination polymers from a waste metal solution that can be generalized on any waste solution.