Synthetic Water-Gel Crystals (Orbeez Balls) as Environmentally Friendly Adsorbent for Removal of Toxic Brilliant Green Dye From Aqueous Solutions
Haneen H. Ghazi, Aseel M. Aljeboree
Abstract
Water pollution caused by dyes is a major threat to marine organisms. Hydrogels (decorative balls),  called water-gel crystals, are widely used to treat wastewater pollution caused from toxic dyes. This study aims to  remove Brilliant Green (BG), a toxic harmful pigment that can cause widespread biota and environmental damage,  from the aqueous solution. Water-Gel Crystals efficiently eliminate BG in a short time frame. Furthermore, several  variables, such as counting equilibrium time, pH solution, the concentration of BG dye and adsorbent dosage were  investigated. The results of this study exhibited that the adsorption equilibrium increased as BG dye concentration  increased at pH = 7 after an equilibrium time of 2h, with 0.1 g of water-gel crystals having the top adsorption  efficiency at 95.567 mg/g. This water-gel crystals adsorbent is regarded as an effective candidate that can be utilised  for water treatment because the re-usability method of produced beads can successfully complete four cycles, and  the adsorbent maintained its ability to remove BG dye. The water-gel crystals are therefore excellent candidates to  be used as potent BG dye adsorbents from aqueous solutions. The water-gel crystals regeneration and re-usability  investigation for the removal of BG dye was completed in at least four cycles successfully. This indicates that the  Water-Gel Crystals produced have a high adsorption value. The (ΔG) was negative for the adsorption processes,  indicating that the process was spontaneous. In addition, (ΔH) was determined for the adsorption method utilising  water-gel crystals at 5.146 KJ/mol. ΔH Positive indicates that the method is endothermic in the range of 15-35  °C, using water-gel crystals.