Cotton Fiber and Carbon Materials Filters for Efficient Wastewater Purification

Abstract

Carbon materials and cotton fibers (CFs) are eco-friendly and cost-effective solutions for water purification. However, enhancing the filtration efficiency of these materials remains challenging. In this study, the capacity of heat-treated sorbents (CFs and low-temperature graphite intercalation compounds (LT-GICs)) to improve the efficiency of wastewater purification from heavy metals and petroleum compounds, was investigated. The properties of the thermally modified CFs were studied in order to obtain a material which is highly efficient in purifying wastewater from heavy metal ions (HMIs). The duration of sorption equilibrium and the optimal ratio of heat-treated cotton fibers (HTCFs) and wastewater were determined. The adsorption capacities of CFs for iodine and methylene blue were determined before and after the heat treatment. Experimental results indicated that thermal treatment of CFs resulted in increased numbers of micropores and mesopores, indicating a high sorption capacity for petroleum products (PPs) in wastewater (A = 11.5 g/g) with an efficiency score of 90%. Furthermore, LT-GIC/CF composite filters were optimized for efficient purification. The results indicated that a filter with a composition of 1 g LT-GIC + 3 g CF had the highest sorption capacity for HMIs (28.7 mg/g) and PPs (80.6%) due to its looser surface structure. The X-ray phase analysis of the sintered composite filters showed the presence of carbon in the amorphous phase, which had a similar structure to the activated carbon from black coal. In summary, the high sorption capacities and simple preparation processes of LT-GIC/CF composites make them potential candidates for wastewater purification.

Keywords

• cotton fibers
• heavy metals
• low-temperature graphite intercalation compounds
• petroleum products
• wastewater purification