425
isopropoxide is dissolved in acetic acid to obtain a transparent sol after a few minutes. Then magnesium pre-prepared slurry is added to the formed sol under continuous stirring. After about 5 h, a sol is achieved. The sol is kept in an oven at 80 °C to
be converted to the gel. The obtained gel is finally dried at 100 °C to produce a
powder. For the dehyroxylation purpose, the prepared powder is calcined at temperatures> 500 °C to obtain TiO 2 –MgO mixed metal oxide powder (Bayal and
Jeevanandam 2014).
Hydrothermal Method
Hydrothermal method is an important approach for preparation of advanced materials. This method involves any heterogeneous chemical reaction in water medium
above ambient temperature and the pressures higher than 1 bar in an appropriate
autoclave. The hydrothermal synthesis encompasses the crystal growth, phase transformation of crystal, and phase equilibrium (Byrappa and Adschiri 2007). In a typical hydrothermal approach for the synthesis of core–shell Fe 3 O 4 @C, given amounts
Fig. 16.11 The sol–gel method is performed in organic solvents and water, and the precursors
used are usually metal halides and metal alkoxides. The sol–gel process can lead to the production
of dense and porous materials. [Available on line: http://en.wikipedia.org/wiki/Sol-gel (Accessed
on 20 September 2019)]
16 Hybrid Adsorbents for Dye Removal from Wastewater
isopropoxide is dissolved in acetic acid to obtain a transparent sol after a few minutes. Then magnesium pre-prepared slurry is added to the formed sol under continuous stirring. After about 5 h, a sol is achieved. The sol is kept in an oven at 80 °C to
be converted to the gel. The obtained gel is finally dried at 100 °C to produce a
powder. For the dehyroxylation purpose, the prepared powder is calcined at temperatures> 500 °C to obtain TiO 2 –MgO mixed metal oxide powder (Bayal and
Jeevanandam 2014).
Hydrothermal Method
Hydrothermal method is an important approach for preparation of advanced materials. This method involves any heterogeneous chemical reaction in water medium
above ambient temperature and the pressures higher than 1 bar in an appropriate
autoclave. The hydrothermal synthesis encompasses the crystal growth, phase transformation of crystal, and phase equilibrium (Byrappa and Adschiri 2007). In a typical hydrothermal approach for the synthesis of core–shell Fe 3 O 4 @C, given amounts
Fig. 16.11 The sol–gel method is performed in organic solvents and water, and the precursors
used are usually metal halides and metal alkoxides. The sol–gel process can lead to the production
of dense and porous materials. [Available on line: http://en.wikipedia.org/wiki/Sol-gel (Accessed
on 20 September 2019)]
16 Hybrid Adsorbents for Dye Removal from Wastewater