Photochemical degradation of fatty amine flotation collectors

The photochemical degradation of four typical fatty amine flotation collectors, decyl propyl ether amine, dodecyl propyl ether amine, laurylamine, and stearylamine, in water was studied. The results of biodegradation tests (the ratio of BOD/CODCr) showed the four flotation collectors were difficult to be biodegraded. The UV/H2O2/air oxidation method was suitable for degrading fatty amine flotation collectors. This method was significant with advantages such as high degradation rate, mild reaction conditions, easy operation, and without secondary pollution. The degradation sequence which was consonant with the COD degradation sequence was the following: decyl propyl ether amine>laurylamine>dodecyl propyl ether amine>stearylamine. Under the conditions of the pH value of 4.5, the initial concentration of 10 mgL-1, and 1% of H2O2 as catalyst, the degradation rate of decyl propyl ether amine reached 99.99% and the COD removal rate reached 78.06% after 15 min ultraviolet irradiation. The IR spectra of wastewater simulated with two typical fatty amine flotation collectors of decyl propyl ether amine and stearylamine were studied and the mechanism of degradation of fatty amine flotation collectors by the UV/H2O2/air oxidation method was discussed.