abstract
- Plastic derived carbon nanotubes (CNTs) were tested as catalysts in persulfate activation for the first time. Four catalysts were prepared by wetness impregnation and co-precipitation (using Al2O3, Ni, Fe and/or Al) and implemented to grow CNTs by chemical vapour deposition (CVD) using low-density polyethylene (LDPE) as carbon feedstock. A catalyst screening was performed in batch mode and the best performing CNTs (CNT@Ni+Fe/Al2O3-cp) led to a high venlafaxine mass removal rate (3.17 mg g- 1 h- 1) in ultrapure water after 90 min (even with a mixture of micropollutants). Its degradation increased when the matrix was replaced by drinking water and negligibly affected in surface water. A composite polymeric membrane was then fabricated with CNT@Ni+Fe/Al2O3-cp and polyvinylidene fluoride (PVDF), a high venlafaxine mass removal rate in surface water being also observed in 24 h of continuous operation. Therefore, the results herein reported open a window of opportunity for the valorisation of plastic wastes in this catalytic application performed in continuous mode.
- This work was financially supported by project POCI-01-0145- FEDER-031439 (PLASTIC TO FUEL&MAT) funded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI), and by national funds (PIDDAC) through FCT/MCTES. We would also like to thank the scientific collaboration under Base- UIDB/50020/2020 and Programmatic- UIDP/50020/2020 Funding of LSRE-LCM - funded by national funds through FCT/MCTES (PIDDAC), Base Funding UIDB/00690/2020 of the Centro de Investigação de Montanha (CIMO) - funded by national funds through FCT/ MCTES (PIDDAC), and projects NORTE-01-0145-FEDER-031049 (InSpeCt - PTDC/EAM-AMB/31049/2017) funded by FEDER funds through NORTE 2020 - Programa Operacional Regional do NORTE, and by national funds (PIDDAC) through FCT/MCTES, and NORTE-01-0145- FEDER-000069 (Healthy Waters) funded by NORTE 2020 under the PORTUGAL 2020 Partnership Agreement through FEDER. Fernanda Fontana Roman also thanks to the FCT for the individual research grant SFRH/BD/143224/2019. Technical assistance with SEM analysis is gratefully acknowledged to CEMUP team.