Characterization and determination of the thermodynamic and kinetic properties of the adsorption of molybdenum (VI) onto microcrystalline anthracene modified with 8-hydroxyquinoline

A reliable and effective method for the determination of trace molybdenum in effluents is proposed. Molybdenum (VI) is analyzed by Microwave Plasma Torch Optical Emission Spectrometry (MPT-OES) based on the adsorption collection onto microcrystalline anthracene modified with 8-hydroxyquinoline. The possible reaction mechanism was discussed in detail and the optimum conditions for adsorption of Mo (VI) were confirmed. The experimental data were fitted well with the pseudo-second-order kinetic model and Langmuir model at all studied temperatures. The calculated thermodynamic parameters (ΔGӨ, ΔHӨ and ΔSӨ) showed that the adsorption of molybdenum onto microcrystalline anthracene was feasible, spontaneous and endothermic at 280–320 K. The recovery of this method is in the range of 96.5%–103.3% with preconcentration factor of 100 and the limit detection after preconcentration is 0.078 μg L− 1. The proposed method has been successfully applied to the determination of trace Mo (VI) in environmental water samples with satisfactory results.

► The preparation of the sorbent, MICRO-AN-8-hydroxyquinoline, is relatively simple. ► Excellent properties of the sorbent have been illustrated in detail. ► Exhaustive data concerning Mo(VI) adsorption behavior are provided. ► Adsorption mechanism is firstly discussed from the view of ion-exchange reaction. ► Offer reference for the studies on other metal ions adsorption onto the sorbent.