Photocatalytic Processes for the Removal of Dye - Green Chemistry for Dyes Removal from Wastewater - page 139

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Removal of Dyes from Effluents Using
Biowaste-Derived Adsorbents
Pejman Hadi 1 , Sanjay K. Sharma 2 and Gordon McKay *,1
1 Chemical and Biomolecular Engineering Department, Hong Kong University of
Science and Technology, Clear Water Bay Road, Hong Kong SAR
2 Green Chemistry & Sustainability Research Group, Department of Chemistry,
JECRC University, Jaipur, India
Abstract
The removal of dyes from aqueous media has always been the focus of attention
since the invention of the dyeing industry. Dyes not only disturb the visual appear-
ance of the aquatic environment, but can also negatively affect human health due
to their toxicological, carcinogenic and mutagenic nature.
The hazards associated with these materials have inspired scientists to look for
different technologies to remove these toxic substances from effluents. It is now
well-established that adsorption/ion exchange is a much preferred technique over
the traditional wastewater treatment methods owing to its ease of process, effec-
tiveness and no sludge formation.
Notwithstanding the very promising dye removal efficiency of activated car-
bon materials, their high cost has incited debate on the economic aspects of these
materials. In the last few decades, researchers have employed many different types
of waste materials to develop various porous carbonaceous and siliceous materials
to act as adsorbents for dye removal.
This chapter will primarily provide an overview of the relevant studies reported
in literature undertaken to modify waste materials and use them for dye adsorp-
tion. Furthermore, the advantages and disadvantages of the waste-produced
adsorbents, their comparative uptake capacities as well as the relevant challenges
will be addressed.
Keywords: Dye removal, adsorption, ion exchange, waste materials, activated
carbon, wastewater treatment