This study focuses on evaluating the carbonation potential of argon oxygen decarburization (AOD) slag and analyzing influence mechanism of carbonation on chromium leachability . Static thin-film accelerated carbonation and sequential leaching tests were carried out. Results show that the liquid to solid (L/S) ratio was the most influencing factor for AOD slag’s carbonation, and the maximum carbonation ratio of AOD slag was 50–52% (L/S = 0.4 mL/g, P CO2 = 7.5 bar, and t > 6 h). Dicalcium silicate’s carbonation resulted in the generation of amorphous calcium carbonate , crystalline calcite and silica gel . AOD slag’s smooth surface could be eroded by these products gradually with carbonation furthered. The mineral phase evolution clearly influenced the mineral phase hydrolysis and physical encapsulation, and thus affected the hydrolysis behavior of the primary phase and the generation behavior of the secondary phase in the carbonated slags. Chromium leachability (20 days) declined to its lowest value (1.7 mg/kg) as the carbonation ratio growing to 23% and then increased to its highest value (7.9 mg/kg) with the carbonation ratio increasing to 52%. Chromium leachability varies with the carbonation ratio. The optimal carbonation ratio that resulting in minimum chromium leaching risk must be taken full in mind before using AOD slag in carbonation-related production activities.
Biofouling was a considerable issue in the water treatment by membrane technology. In this study, high anti-bacterial property Ag-MOF was synthesized followed by embedding into polyamide layer with vacuum-assisted interfacial polymerization process to prepare an Ag-MOF incorporated membrane. The successful preparation of Ag-MOF and membranes was verified by FT-IR, FESEM, XPS, XRD, BET, zeta potential and contact angle test. On account to the strong hydrophility, porous structure, electronegativity and antibacterial property of Ag-MOF, modified membranes showed excellent performance for dyes, salts and bacteria. The water permeability of modified membranes was increased from 9.2 to 14.3 L m -2 h −1 bar −1 and the rejection rate of MO, MB and RB of the optimum membranes were 95.4%, 87.8% and 99.3%, respectively. The rejection rate of Na 2 SO 4 and MgSO 4 were increased from 54.0% and 36.6% to 84.1% and 73.1%. The sterilization rate of modified membranes to E. coli and S. aureus both exceeded 99%. The leaching test of Ag + evaluated the potential mechanism of anti-bacterial property. Moreover, dynamic bio-fouling test were used to detect the actual status in the filtration process. Those results suggested that modified membranes showed a strong resistance to bio-foulants thus enlarged the scope of application of membranes for water treatment.