A sustainable bio-carrier medium for wastewater treatment: Modified basalt fiber

Bio-carrier plays important roles in the performance of biological contact oxidation reactors for wastewater treatment. Most of the conventional bio-carriers are polymeric. Developing more sustainable materials is necessary to reduce the overconsumption of petrochemicals and second pollution after disposal. This work studied the inorganic basalt fiber (BF) fabricated from nature basalt rock as a green and sustainable bio-carrier medium for wastewater treatment. To improve the bio-affinity, the silica-based BF was modified with a hydrophilic cationic polymer (hexadecyl trimethyl ammonium chloride, CTAC). The modified basalt fiber (MBF) showed a more hydrophilic and positively charged surface. The bio-affinity of BF and MBF bio-carriers were evaluated in Bacillus subtilis adhesion and activated sludge immobilization tests. The influence of CTAC coating on the initial adhesion of bacteria and subsequent biomass immobilization was investigated. The results showed that MBF bio-carriers had higher biomass attachment capacity and microorganism diversity with shorter biofilm formation time. The reported MBF provided an environmental-friendly, sustainable and economical alternative to conventional bio-carriers for wastewater treatment.