Treatment of Cutting Fluid Waste using Activated Carbon Fiber Supported Nanometer Iron as a Heterogeneous Fenton Catalyst.

Addressing the problem of high chemical oxygen demands (COD) of cutting fluid waste generated in the machining process, its complex composition, and the specific conditions required for the treatment process, a heterogeneous Fenton fibre catalyst (NZVI@ACF) made of nanometer-iron supported on activated carbon fiber using dip-molding was developed. NZVI was homogeneously loaded onto ACF surfaces to form NZVI@ACF, with a specific surface area (S) of 726.3642 m/g. Using a multistage chemical pretreatment, the NZVI@ACF/HO system was used to effectively treat cutting fluid waste. The results indicated that the rate of COD removal in the cutting fluid waste liquid pretreated with NZVI@ACF/HO system was 99.8% when the reactions conditions were optimized to 20 nmol/L HO, 6 g/L NZVI@ACF, total reaction time of 120 min and pH 5. The treated waste solution passed China's tertiary wastewater discharge standards. NZVI@ACF/HO demonstrated an excellent catalytic performance compared to the traditional Fenton catalyst, increased the effective pH reaction range and had an adsorption effect on the waste liquid after the reaction.