Synthesis and Characterization of Thiol-Functionalized Polynorbornene Dicarboximides for Heavy Metal Adsorption from Aqueous Solution
Por:
Onchi, Alejandro, Corona-Garcia, Carlos, Santiago, Arlette A., Abatal, Mohamed, Soto, Tania E., Alfonso, Ismeli, Vargas, Joel
Publicada:
1 jun 2022
Resumen:
The contamination of water resources with heavy metals is a very serious
concern that demands prompt and effective attention due to the serious
health risks caused by these contaminants. The synthesis and
ring-opening metathesis polymerization (ROMP) of norbornene
dicarboximides bearing thiol pendant groups, specifically,
N-4-thiophenyl-exo-norbornene-5,6-dicarboximide (1a),
N-4-(methylthio)phenyl-exo-norbornene-5,6-dicarboximide (1b) and
N-4-(trifluoromethylthio)phenyl-exo-norbornene-5,6-dicarboximide (1c),
as well as their assessment for the removal of heavy metals from aqueous
systems, is addressed in this work. The polymers were characterized by
NMR, SEM and TGA, among others. Single and multicomponent aqueous
solutions of Pb2+, Cd2+ and Ni2+ were employed to perform both kinetic
and isothermal adsorption studies taking into account several
experimental parameters, for instance, the initial metal concentration,
the contact time and the mass of the polymer. In general, the adsorption
kinetic data fit the pseudo-second-order model more efficiently, while
the adsorption isotherms fit the Freundlich and Langmuir models. The
maximum metal uptakes were 53.7 mg/g for Pb2+, 43.8 mg/g for Cd2+ and
29.1 mg/g for Ni2+ in the SH-bearing polymer 2a, 46.4 mg/g for Pb2+,
32.9 mg/g for Cd2+ and 27.1 mg/g for Ni2+ in the SCH3-bearing polymer 2b
and 40.3 mg/g for Pb2+, 35.9 mg/g for Cd2+ and 27.8 mg/g for Ni2+ in the
SCF3-bearing polymer 2c, correspondingly. The better performance of
polymer 2a for the metal uptake was ascribed to the lower steric
hindrance and higher hydrophilicity imparted by -SH groups to the
polymer. The results show that these thiol-functionalized polymers are
effective adsorbents of heavy metal ions from aqueous media.
Filiaciones:
Onchi, Alejandro:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Unidad Morelia, Antigua Carretera Patzcuaro 8701, Morelia 58190, Michoacan, Mexico
Corona-Garcia, Carlos:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Unidad Morelia, Antigua Carretera Patzcuaro 8701, Morelia 58190, Michoacan, Mexico
Santiago, Arlette A.:
Univ Nacl Autonoma Mexico, Unidad Morelia, Escuela Nacl Estudios Super, Antigua Carretera Patzcuaro 8701, Morelia 58190, Michoacan, Mexico
Abatal, Mohamed:
Univ Autonoma Carmen, Fac Ingn, Ave Cent S-N Esq Con Fracc Mundo Maya, Ciudad del Carmen 24115, Campeche, Mexico
Soto, Tania E.:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Unidad Morelia, Antigua Carretera Patzcuaro 8701, Morelia 58190, Michoacan, Mexico
Alfonso, Ismeli:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Unidad Morelia, Antigua Carretera Patzcuaro 8701, Morelia 58190, Michoacan, Mexico
Vargas, Joel:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Unidad Morelia, Antigua Carretera Patzcuaro 8701, Morelia 58190, Michoacan, Mexico
Green Published, gold, Gold, Green
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