Pursuing the effect of aeration, pH increment, and H2O2 coupled with UV irradiation on the removal efficiency of manganese by microfilter membrane

Abstract

Aeration, a very common method used in conventional water treatment industries for oxidation and mixing purposes, was used along with pH increment for removal of manganese by microfilter membrane. However, experiments showed that aeration instead of accelerating the manganese oxidation process as normally expected rather declined the manganese removal percentage by a noticeable difference from that obtained by pH increment alone. As high as 97% manganese removal could be attained by microfilter membrane with an increased pH level of 9.7 of the raw water, whereas the removal percentage was reduced to 60% when the mechanical aeration was incorporated. H2O2, being activated by UV light decomposes into very reactive OH-radical which is of very high oxidizing potential and can break down or change the physical properties of even very strongly-bonded compounds which then can be removed by any suitable physical means. From this principle, H2O2 coupled with UV irradiation was also included in the experiment of manganese removal by microfilter membrane to pursue it's manganese removal efficiency. However, experiments showed that a negative manganese removal occurred with amount of manganese in the filter water surpassing the amount of manganese in the raw water. Also a very high trend in the manganese and turbidity level was found in the membrane washed drain water, which helped conclude that H2O2 coupled with UV irradiation should not be used as a process for manganese removal by microfilter membrane, rather it can be used as a process for washing of the membrane module.