(Yin et al. 2013). The fabrication of this hybrid electrode material has been presented
in Fig. 1.8.
1.5 Oil
Oil contamination of water is a very serious issue. Large volume of oil enters the
water bodies from industries, such as petroleum refining and oil extraction, and from
oil spill incidents. Efficient removal of oil from water via oil/water separation is,
therefore, required to ensure proper treatment of oily wastewater. This section is
dedicated to this issue, containing discussions on selected major reported research
works in this area involving the use of metal oxides. For detailed literature review on
this subject, the readers may refer to Ma et al. (2016).
Adopting a typical membrane filtration method, Lu et al. (2016) used a number of
metal oxides as deposits on ultrafiltration membranes made of ceramics. The metal
oxides used were CeO 2 , CuO, MnO 2 , Fe 2 O 3 and TiO 2 , all having an average size of
10 nm. It was inferred that the more the hydrophilic nature of the metal oxide, the
more efficient it is as a material for filtration layer of a ceramic membrane. As a
consequence, the most hydrophilic oxide Fe 2 O 3 (among the studied oxides)deposited membrane showed the least tendency towards irreversible fouling, high
chemical oxygen demand rejection percentage and the highest normalized initial
permeate flux for up to 7 cycles of filtration. Zhu et al. (2010) fabricated an
innovation polysiloxane-coated magnetic Fe 2 O 3 @C core-shell nanoparticulate
adsorbent to remove oil from oil/water mixture. These corrosion-resistant
nanoadsorbent showed oil uptake up to ~4 times of their weight, in addition to
their floatable nature that is important considering that oil (light oils) in general floats
on water, and so, interaction between the contaminant oil and the nanoadsorbent will
be more feasible. A photograph of the oil adsorption and removal processes have
been shown in Fig. 1.9. On the other hand, Wang et al. (2013) designed and
Fig. 1.8 Fabrication of graphene aerogel/TiO 2 hybrid electrode material. (Reprinted from Yin et al.
(2013), with permission from Wiley)
1 Metal Oxides as Decontaminants of Water and Wastewater
13
in Fig. 1.8.
1.5 Oil
Oil contamination of water is a very serious issue. Large volume of oil enters the
water bodies from industries, such as petroleum refining and oil extraction, and from
oil spill incidents. Efficient removal of oil from water via oil/water separation is,
therefore, required to ensure proper treatment of oily wastewater. This section is
dedicated to this issue, containing discussions on selected major reported research
works in this area involving the use of metal oxides. For detailed literature review on
this subject, the readers may refer to Ma et al. (2016).
Adopting a typical membrane filtration method, Lu et al. (2016) used a number of
metal oxides as deposits on ultrafiltration membranes made of ceramics. The metal
oxides used were CeO 2 , CuO, MnO 2 , Fe 2 O 3 and TiO 2 , all having an average size of
10 nm. It was inferred that the more the hydrophilic nature of the metal oxide, the
more efficient it is as a material for filtration layer of a ceramic membrane. As a
consequence, the most hydrophilic oxide Fe 2 O 3 (among the studied oxides)deposited membrane showed the least tendency towards irreversible fouling, high
chemical oxygen demand rejection percentage and the highest normalized initial
permeate flux for up to 7 cycles of filtration. Zhu et al. (2010) fabricated an
innovation polysiloxane-coated magnetic Fe 2 O 3 @C core-shell nanoparticulate
adsorbent to remove oil from oil/water mixture. These corrosion-resistant
nanoadsorbent showed oil uptake up to ~4 times of their weight, in addition to
their floatable nature that is important considering that oil (light oils) in general floats
on water, and so, interaction between the contaminant oil and the nanoadsorbent will
be more feasible. A photograph of the oil adsorption and removal processes have
been shown in Fig. 1.9. On the other hand, Wang et al. (2013) designed and
Fig. 1.8 Fabrication of graphene aerogel/TiO 2 hybrid electrode material. (Reprinted from Yin et al.
(2013), with permission from Wiley)
1 Metal Oxides as Decontaminants of Water and Wastewater
13