Review on solvent desorption study from exhausted adsorbent

Hazardous solid waste is one of the most serious problem faced by all over the World, which comprises spent solid adsorbents. Spent solid adsorbents are generally regenerated by different methods including solvent desorption, owning its merits and demerits. Basic information of desorption and eluent like desorption efficiency, desorption cycle, desorption breakthrough curve and eluent parameters are elucidated. Main objective of this review paper is explored batch and column desorption of metal, dye and other hazardous compounds using ion exchange compounds (such as acid and alkaline solution), organic solvent and mixture of these as an eluent in desorption study; and revealed that desorption is mostly depends upon ion exchange process. Desorption of positively charged metals is conducted using acid eluent, while alkaline solution is used to elute negatively charged dyes and other contaminations due to electrostatic attraction. Acidic eluent hydrochloric acid and alkaline eluent sodium hydroxide solution are most utilized for desorption study to elute copper(II) and anionic dye. Feasibility of these eluents using desorption cycles and its efficiency is also discussed in this paper.