Figure 4.

The effect of cations concentration on the flocculating activity of bioflocculant dosage from Bacillus nitratireducens towards EBT solution. Experiment composition: 10 mL of EBT (1 g/L) with 390 mL of deionized (D.I), pH 2 adjusted with NaOH (1 M) and/or H₂SO₄ (0.5 M), 100 mL of nutrient broth containing Bacillus nitratireducens, and 5 mL of salt solution (CaCl₂, AlCl₃, KCl, or MgCl₂) at a concentration of 10 g/L (except for the experiments with only bioflocculant, with no salt).