In
this study, the solid–liquid equilibrium (SLE) data of
3-methyl-2-nitrobenzoic acid (3-M-2-NBA), 3-methyl-4-nitrobenzoic
acid (3-M-4-NBA), and 5-methyl-2-nitrobenzoic acid (5-M-2-NBA) in n-butanol, iso-butanol, tert-butanol, and sec-butanol were
determined using the method of dynamic laser at atmospheric pressure.
The experimental SLE data indicate that within the temperature range
studied (290.15–348.95 K), the solubilities of 3-M-2-NBA, 3-M-4-NBA,
and 5-M-2-NBA in the above four solvents are proportional to the temperature.
The molar fraction of solubility of the same solute in different solvents
from low to high is as follows: iso-butanol < n-butanol< sec-butanol < tert-butanol. The molar fraction of
solubility of the three solutes in the same solvent from low to high
is as follows: 3-M-4-NBA < 3-M-2-NBA<5-M-2-NBA. The experimental
data were correlated using the Apelblat model, λh model, and
NRTL activity coefficient model, and the calculated solubilities agree
satisfactorily with the measured results. The best model for every
system was selected using the result of Akaike information criterion
analysis.