Background: Potable, clean and safe water is the basic need for all human beings. Major portion
of the earth is occupied by water, however, this is contaminated by rapid industrialization, improper
sewage and natural calamities and man-made activates, which produce several water-borne and fetal
diseases. In this review we presented some recent patent for environmental remediation.
Methods: Various technologies have been developed for the treatment of waste water consist of chemical,
membrane, filtration, sedimentation, chlorination, disinfection, electrodialysis, electrolysis, reverse
osmosis and adsorption. Among these entire phenomenon’s, adsorption was the most efficient method
for wastewater treatment, because it is a quick and cheap technology which signifies extensive practical
applications. Adsorption phenomenon has been tactfully used for the removal of biological waste as
well as soluble and insoluble material with a removal efficacy of 90-99%.
Results: Clean water supply is limited to human beings. The people in the developing countries have
less or no access to the clean and potable water. The shortage of potable water resources and long term
safe water deficiencies are some of the leading problems worldwide. In this review, we have explained
in the detail adsorption phenomena of chitosan, pharmaceutical importance and other applications. It is
worth to say that adsorption technologies using chitosan and its derivative is one of the quickest and
cost effective methods for the wastewater treatment. The review comprises of ninety eight references.
This review also covers various patents vis-a-vis the role of chitosan-nanocomposite in environmental
application for wastewater treatment.
Conclusion: Chitosan is a pseudo-neutral cationic polymer which is formed by the de-acetylation of
chitin polymer. Various patent on chitosan and chitosan-nanocomposite were taken into account related
to wastewater purification. We have found that chitosan and chitosan-nanocomposite are used for the
removal of viruses, bacteria, cryptosporidium oocysts and giardia cysts, soluble and insoluble organic
pollutants, poly aromatic hydrocarbons and heavy metals from wastewater. In this study, we also found
that chitosan and chitosan-nanocomposite are selected for the removal of transition metals.