Application of Sustainable and Low-Cost Sludge-Based Adsorbents …
41
the adsorbents. The amount of dye adsorbed increased with increase in agitation
time. In case of GAC, the initial rate of dye uptake was rapid and it rapidly attained
equilibrium for low initial dye concentration. Similar results have been reported in
the literature on the extent of removal of dyes [57]. The isothermal plot of GAC and
CBBA differs from each other since CBBA has not much micro- and macroporous
structure. The maximum adsorption capacities of GAC and CBBA were 6.58 mg/g
and 4.02 mg/g, respectively.
2.5.3 Basic Oxygen Furnace Slag
Basic oxygen furnace slag (BOF slag), a final waste material in the basic oxygen
furnace steelmaking process [83], was also used in adsorption studies for the colour
removal of synthetic reactive dyes such as Reactive Blue 19, Reactive Black 5
and Reactive Red 120. Reactive Red 120 showed the lowest adsorption due to its
large molecular weight and complex structure. The Langmuir and Redlich–Peterson
isotherm models fitted the experimental data with higher coefficients than Freundlich
model. The first-order kinetic model followed the isothermal plot due to higher correlation coefficient. This is generally in agreement with the published research that the
first-order kinetic model was able to describe adsorption process [13]. Amin [7]
selected three different activated carbons prepared by chemical and physical activation of sugar bagasse pith in the absence of air at 600 °C for the removal of Reactive
orange dye.
2.5.4 Other Industrial Inorganic Used Resources
Over the years, a number of workers have used different waste materials such as
coal fly ash [53, 105], coal bottom ash [21, 38], bagasse fly ash [39], blast furnace
slag [37], deoiled soya [78, 79], red mud [38] and sawdust [35] from industrial and
agricultural products, as adsorbent for the removal of different pollutants. Recently,
apart from these commonly used waste materials the authors have been trying to
utilize waste materials from the boron industry to remove hazardous dyes [11]. The
adsorption of both dyes onto boron waste was exothermic in nature with dye removal
capacity slightly decreasing with increasing temperature [90]. The maximum adsorption capacities on Basic Yellow 28 and Basic Red 46 were 75.00 and 74.73 mgg
−1 ,
respectively. From the reported results, it would appear that boron waste is an
adsorbent offering greater wastewater treatment potential than other waste materials.
2.5.5 Industrial Organic Wastes
Pala et al. [96] conducted a comparative study of activated carbons prepared from
solvent extracted olive oil pulp for textile reactive azo dye removal from aqueous
streams. These residues showed a surface area of 800 m
2 /g and a pore volume
41
the adsorbents. The amount of dye adsorbed increased with increase in agitation
time. In case of GAC, the initial rate of dye uptake was rapid and it rapidly attained
equilibrium for low initial dye concentration. Similar results have been reported in
the literature on the extent of removal of dyes [57]. The isothermal plot of GAC and
CBBA differs from each other since CBBA has not much micro- and macroporous
structure. The maximum adsorption capacities of GAC and CBBA were 6.58 mg/g
and 4.02 mg/g, respectively.
2.5.3 Basic Oxygen Furnace Slag
Basic oxygen furnace slag (BOF slag), a final waste material in the basic oxygen
furnace steelmaking process [83], was also used in adsorption studies for the colour
removal of synthetic reactive dyes such as Reactive Blue 19, Reactive Black 5
and Reactive Red 120. Reactive Red 120 showed the lowest adsorption due to its
large molecular weight and complex structure. The Langmuir and Redlich–Peterson
isotherm models fitted the experimental data with higher coefficients than Freundlich
model. The first-order kinetic model followed the isothermal plot due to higher correlation coefficient. This is generally in agreement with the published research that the
first-order kinetic model was able to describe adsorption process [13]. Amin [7]
selected three different activated carbons prepared by chemical and physical activation of sugar bagasse pith in the absence of air at 600 °C for the removal of Reactive
orange dye.
2.5.4 Other Industrial Inorganic Used Resources
Over the years, a number of workers have used different waste materials such as
coal fly ash [53, 105], coal bottom ash [21, 38], bagasse fly ash [39], blast furnace
slag [37], deoiled soya [78, 79], red mud [38] and sawdust [35] from industrial and
agricultural products, as adsorbent for the removal of different pollutants. Recently,
apart from these commonly used waste materials the authors have been trying to
utilize waste materials from the boron industry to remove hazardous dyes [11]. The
adsorption of both dyes onto boron waste was exothermic in nature with dye removal
capacity slightly decreasing with increasing temperature [90]. The maximum adsorption capacities on Basic Yellow 28 and Basic Red 46 were 75.00 and 74.73 mgg
−1 ,
respectively. From the reported results, it would appear that boron waste is an
adsorbent offering greater wastewater treatment potential than other waste materials.
2.5.5 Industrial Organic Wastes
Pala et al. [96] conducted a comparative study of activated carbons prepared from
solvent extracted olive oil pulp for textile reactive azo dye removal from aqueous
streams. These residues showed a surface area of 800 m
2 /g and a pore volume