Synthesis of Gamma Alumina (γ-Al2O3) Filament Granules for Removal of Lead and Chromium from Water in a Fixed Bed Continuous Reactor

One of the most important problems in today's world, which is accompanied by industrial development and population growth, is the pollution of the environment, especially water sources, with toxic and dangerous heavy metals. In this study, the synthesis and application of activated gamma alumina filament granules in the removal of chromium and lead from water in a continuous fixed-bed reactor with an upward flow have been investigated. For the preparation of active gamma alumina, thermal method is used, and furfuran binder as well as phenolic resin and polyvinyl alcohol are used to form it and it is converted into filaments by an extruder. Agilent 240 AA atomic absorption spectrometer was used to measure the concentration metal ions and Thomas model was used to predict the behavior of the column. The results showed that the percentage of removal at the column height of 20 cm is at its maximum (70.7% for chromium and 94% for lead). It was found that by increasing the initial concentration of the pollutant and increasing the flow rate, the failure time decreases. The highest adsorption capacity of activated gamma alumina reactor for chromium is 20.7 mg/g and for lead 1.31 mg/g (column height 20 cm, flow rate 4.5 mL/min, concentration 10 mg/L, and pH equal to 3 for Chromium and pH equal to 7 for lead) were obtained. Formed activated gamma alumina is an effective adsorbent for adsorbing heavy metals, especially chromium and lead, due to its optimal adsorption, ease of preparation, and reasonable price.