To study the influence of NaCl on the desorption efficiency, four desorption solvents were prepared with varying NaCl concentrations namely: RS1 (no salt), RS2 (10 mM NaCl), RS3 (50 mM NaCl) and RS4 (500 mM NaCl). After 72 hours of adsorption, the adsorbent was recovered by filtration and placed respectively in 20 mL desorption solvent containing the above NaCl concentrations to be continuously stirred for another 72 hours at room temperature. Sample preparation for NMR analysis followed the steps mentioned previously.