Batch and column adsorption of dye contaminants using a low-cost sand adsorbent

In the current study, the sand collected from a specific location called Ruba Al-Khali in Saudi Arabia has been identified and efficiently used for the removal of dye contaminate through adsorption process. It was found that the crystalline SiO₂ (including quartz and cristobalite SiO₂) is the major component in the micrometer-sized sand adsorbent with lava-like rough surface. Batch adsorption experiments were investigated and discussed by using Rhodamine B (RhB) as the model toxic contaminant. The adsorption of RhB with the exothermic nature is considered to be more favorably by the pseudo-second-order model. The corresponding adsorption capacity at room temperature is examined at around 2.94 mg g^-1 by Langmuir fitting. Furthermore, the effects of empty bed contact time, initial concentration, and the pH value of RhB solution on the breakthrough point in the column adsorption process were investigated.