44
A. Geethakarthi
Red 120 and Reactive Red 141. This behaviour implied an exothermic process for
Reactive Red 2 but an endothermic process for Reactive 120 and Reactive 141. The
adsorption of less charged dyes (Reactive Dye 2) was mainly physical but that for
more charged dyes (Reactive Red 120 and Reactive Red 141) was chemical based on
the enthalpy values of adsorption: 5.5, 2.77 and 6.41 kJ/mol. Decreasing adsorption
efficiency of metal hydroxide with higher dye concentration was due to the presence
of anionic electrolytes (NaCl and Na 2 SO 4 ) in dye solution. Studies have proven the
possible effective use for paper sludge ash in the preparation of low-cost sorbents
for water purification, using steam and calcination treatments by Hojamberdiev et al.
[48].
Paper Sludge
The press mud, end derivative obtained after the paper sludge treatment process is
used in agriculture to improve soil fertility due to its high carbon content [44, 111].
This sludge has very high beneficial effects on soils that are deficient in organic matter.
The calcinated paper sludge by mechano-chemical grinding and physical activation
in the presence of nitrogen atmosphere showed relatively higher BET surface area
(70 m
2 /g at 600 °C) than other samples.
2.6 Commercial Activated Carbon
Commercial activated carbon is the most effective adsorbent among the various
adsorbents due to its structural characteristics, porous texture, regenerative capacity
and chemical nature. The activated carbons are derived from starting materials such
as charcoal and coconut husk and have led research towards wide use of pollutant
adsorption in both gaseous and liquid phases. Industries like food and beverage
processing, chemical, pharmaceutical, petroleum, mining, nuclear, automobile and
vacuum manufacturing use adsorbents in their effluent processing units. Commercial
activated carbons are prepared from many carbonaceous materials such as biomass
and organic wastes. Several recent publications [22, 30, 84, 107, 115] indicate the
interest in developing sustainable and environmentally safe recycling processes to
produce value products such as activated carbon from wastes. The properties and
surface chemistry of these adsorbents play a major role in their industrial applications [109]. The active surface area, characteristics and performance of a particular
activated carbon source depend largely on the nature of the material it was manufactured from and the process by which it was activated [43, 67]. This chapter discusses
the incineration of tannery sludge into activated carbon by combined activation and
their application in degradation of reactive dye.
A. Geethakarthi
Red 120 and Reactive Red 141. This behaviour implied an exothermic process for
Reactive Red 2 but an endothermic process for Reactive 120 and Reactive 141. The
adsorption of less charged dyes (Reactive Dye 2) was mainly physical but that for
more charged dyes (Reactive Red 120 and Reactive Red 141) was chemical based on
the enthalpy values of adsorption: 5.5, 2.77 and 6.41 kJ/mol. Decreasing adsorption
efficiency of metal hydroxide with higher dye concentration was due to the presence
of anionic electrolytes (NaCl and Na 2 SO 4 ) in dye solution. Studies have proven the
possible effective use for paper sludge ash in the preparation of low-cost sorbents
for water purification, using steam and calcination treatments by Hojamberdiev et al.
[48].
Paper Sludge
The press mud, end derivative obtained after the paper sludge treatment process is
used in agriculture to improve soil fertility due to its high carbon content [44, 111].
This sludge has very high beneficial effects on soils that are deficient in organic matter.
The calcinated paper sludge by mechano-chemical grinding and physical activation
in the presence of nitrogen atmosphere showed relatively higher BET surface area
(70 m
2 /g at 600 °C) than other samples.
2.6 Commercial Activated Carbon
Commercial activated carbon is the most effective adsorbent among the various
adsorbents due to its structural characteristics, porous texture, regenerative capacity
and chemical nature. The activated carbons are derived from starting materials such
as charcoal and coconut husk and have led research towards wide use of pollutant
adsorption in both gaseous and liquid phases. Industries like food and beverage
processing, chemical, pharmaceutical, petroleum, mining, nuclear, automobile and
vacuum manufacturing use adsorbents in their effluent processing units. Commercial
activated carbons are prepared from many carbonaceous materials such as biomass
and organic wastes. Several recent publications [22, 30, 84, 107, 115] indicate the
interest in developing sustainable and environmentally safe recycling processes to
produce value products such as activated carbon from wastes. The properties and
surface chemistry of these adsorbents play a major role in their industrial applications [109]. The active surface area, characteristics and performance of a particular
activated carbon source depend largely on the nature of the material it was manufactured from and the process by which it was activated [43, 67]. This chapter discusses
the incineration of tannery sludge into activated carbon by combined activation and
their application in degradation of reactive dye.