Thermodynamic Equilibrium Kinetics of Sewage Sludge Ash Pellets for the Removal of Methylene Blue (MB) from Aqueous Solutions

The utilization of Sewage Sludge Ash Pellets (SSAP) as an efficient sorbent material for dye removal is highlighted in this work. On MB removal, the effects of several factors such as contact time, agitation speed, solution pH, adsorbent dosage, and beginning concentration were investigated. When the MB concentration was 25 mg/L, the SSAP concentration was 30 g/L, and the speed was 250 rpm, the maximum removal efficiency was 98 %. The equilibrium time was found to be 60 minutes, and the maximum dye removal occurred at pH 10 for SSAP adsorbents. The Langmuir and Freundlich isotherm models were used to analyze the adsorption data. Adsorption isotherm studies revealed that the Langmuir model fits this case better. In most cases, the R2 correlation coefficient value exceeds 0.95. According to the findings of this study, SSAP can be used as an effective adsorbent for the removal of MB from aqueous solutions.