aFor all experiments, .
bOther parameters: baked at 110 °C, the slurry passed through a sieve having 100 meshes (154 µm pore size), addition of 1.40 ml H2O and agitation at room temperature (24 °C) for 30 min.
cOther parameters: baked at 95 °C for 8 min, the slurry passed through a sieve having 100 meshes ( 154 µm pore size) and agitation at room temperature for 30 min.
dOther parameters: baked for 8 min, the slurry passed through a sieve having 100 meshes (154 µm pore size), addition of 1.40 ml H2O and agitation at room temperature for 30 min.
eOther parameters: baked at 95 °C for 8 min, the slurry passed through a sieve having 100 meshes (154 µm pore size), addition of 1.40 ml H2O and agitation at room temperature.
fOther parameters: baked at 95 °C for 8 min, addition of 1.40 ml H2O and agitation at room temperature for 30 min.
gOther parameters: baked at 95 °C for 8 min, the slurry passed through a sieve having 100 meshes (154 µm pore size), brine concentration being 2.00% (w/w) and agitation at room temperature for 30 min.
hOther parameters: baked at 95 °C for 8 min, the slurry passed through a sieve having 100 meshes (154 µm pore size), addition of 1.40 ml brine and agitation at room temperature for 30 min.
iOther parameters: baked at 95 °C for 8 min, the slurry passed through a sieve having 100 meshes (154 µm pore size), the addition of 1.40 ml brine (2.00%, w/w) and agitation for 30 min.
Table 2 Design and results of response surface experimentation