Vol. 8, Issue 5, Part E (2022)

In batch-type contact operations, a fixed amount of adsorbent is stirred with a fixed amount of contaminated water or a fixed amount of an adsorbate's solution until the contaminant or adsorbate's concentration in the aqueous phase has either dropped to a specified level or has been fully eliminated. According to the requirements, the amount of adsorbent and the duration of contact are adjusted. Following removal, the adsorbent is either discarded or recycled for later use. The concentration of adsorbate species, system agitation speed, amount of adsorbent, adsorbent particle size, etc. all affect how long it takes to reach equilibrium. In the batch adsorption process, single-stage and multi-stage counter-current operation procedures are typically employed. Small volumes of wastewater can only be treated by single stage operations, which rely on fill and draw processes. Large volumes of wastewater must be treated by multistage operations, which are utilised in series and alternate between fill and treat modes. The adsorbent employed for this function is often powdered, increasing surface area while lowering diffusion resistance inside pores. Several contaminants have been removed using the batch technique in the past.