Nanofibrous filtering membranes modified with sucrose-derived carbonaceous materials for adsorption in batch and fixed bed

Membrane technologies have been considered as an efficient and economical alternative to help providing clean water for the population on a large scale. In this regard, the development of low-cost adsorbent membranes, with scalable production and high efficiency is indeed necessary and urgently required. In this work, we investigated the methylene blue removal performance of solution blow spun (SBS) polyamide 6 (PA6) nanofibrous mem-branes (NFMs) coated with different types of carbonaceous materials. Sucrose was employed as carbon source and two distinct approaches, namely hydrothermal and caramelization routes, were investigated to produce it. The NFMs were functionalized by dip-coating and then chemically activated using NaOH to further enhance the adsorption efficiency. The carbonaceous materials-modified NFMs were characterized by scanning electron microscopy (SEM), contact angle, Zeta potential, Fourier-transform infrared spectroscopy (FTIR), X-ray photo-electron spectroscopy (XPS), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). Batch and fixed bed experiments revealed that the NFMs modified by dip coating with the carbonaceous materials present competitive adsorption capacity in addition to be a simple, low cost and scalable strategy. The experi-mental and maximum adsorption capacities of batch adsorption were 371.69 mg/g and 471.58 mg/g for the NFMs modified with hydrothermal carbon, and 260.52 mg/g and 651.04 mg/g for the NFMs coated with black caramel, respectively. The NFMs modified with hydrothermal carbon and caramel carbon showed applicability in scalable systems based on fixed bed adsorption experiments. Our results suggest that nanofibrous membranes coated with carbonaceous materials from sucrose are a suitable tool to develop adsorptive membranes for pol-lutants removal and open the venue to also explore other carbon-rich sources, including bio-and food residues for adsorptive applications.

Automated summary

This study investigates the use of carbonaceous materials coated on solution blow spun polyamide 6 nanofibrous membranes for efficient methylene blue removal. The results show that the dip coating modification with carbonaceous materials offers competitive adsorption capacity along with a simple, low-cost, and scalable strategy for pollutant removal on a large scale.