4. In water treatment systems, Arsenic (As) removal is achieved generally by two consecutive processes. Dissolved As(III
Posted: Thu Jun 09, 2022 9:45 am
4. In water treatment systems, Arsenic (As) removal is achieved generally by two consecutive processes. Dissolved As(III) is first oxidized to As(V), which then is removed by an ion- exchange process. In order to ensure that more than 99% of total As is oxidized before the ion- exchange process, what is the minimum target pe of the water at pH 6.7? (40 pt) AsO4 + 2H+ + 2e → ASO3³ + H₂O peº = 2.64 As species and the pK values are as follows: H3ASO4, H₂ASO4, HASO4, AsO4³, H3ASO3, H₂ASO3, HASO3²-, ASO3³- pKal pka2 pka3 As(III) 9.23 12.10 13.41 As(V) 2.24 6.76 11.60