Ni induced superhydrophobic melamine foam sorbent for cleanup of oils/organic solvents

In this study, hydrophobic behavior of the metal ion-modified commercial acoustic melamine foam (MF) was investigated and its use as a sorbent was evaluated. From a different perspective, secondary modifications with polydopamine (PDA) and 1-octadecanthiol (ODT) were carried out to prevent the metal release and improve hydrophobicity. FTIR, XPS, EDX, and elemental mapping analyses showed that modified MF (PNiMFO) formed a complex with Ni2+, and PDA and ODT modifications were successfully performed. SEM analysis confirmed that MF with an open-cell structure retained its porosity and structural integrity after modification. The results obtained from the compression test, which was carried out to better understand the mechanical behavior, showed that an elastic sorbent could be prepared. After the secondary surface modification, the MF became superhydrophobic and its water contact angle value was determined as 164 degrees. Meanwhile, the oil and organic solvent sorption capacity of this material was investigated under static conditions and it was determined that several pollutants could be sorbed up to 76-180-fold of their weight. Furthermore, this material, which did not release the metal ion to the water source as a secondary pollutant, could be reused for 10 cycles of the sorption-release step without any significant loss in its performance. It is expected that these properties could meet the requirements for the use of PNiMFO as a potential sorbent in environmental applications.

Automated summary

This study investigated the hydrophobic behavior of metal ion-modified commercial acoustic melamine foam (MF) and evaluated its use as a sorbent. Secondary modifications with polydopamine (PDA) and 1-octadecanthiol (ODT) were carried out to prevent metal release and improve hydrophobicity. The modified MF (PNiMFO) formed a complex with Ni2+ and showed superhydrophobicity with a water contact angle of 164 degrees. Furthermore, PNiMFO exhibited high sorption capacity for oil and organic solvents and could be reused for multiple cycles without loss of performance.