1. Introduction
Heavy metals present in the wastewaters discharged
from industries are a subject of major concern for the
environmental issues. The Environmental Protection
Agency (EPA) has assessed the hazards caused by the
various heavy metals. Table 1 shows the discharge limits
of various heavy metals, their potential health effects on
humans along with their sources as per EPA [1].
When these metal ions present at excessive levels in
an aqueous discharge, the stream remains unusable due
to the adverse effects associated with consumption [2].
These metal ions are highly toxic and if they are directly
discharged can cause environmental imbalance and can
damage the subsequent treatments associated in the
wastewater purifcation plants. Therefore, inexpensive
and effcient methods of wastewater purifcation or
improvements in the existing methods will have to be
made to adjust the new requirements [3].
The classical methods such as adsorption, ion
exchange, chemical precipitation and evaporation have
been used for the removal of metal ions from aqueous
effuents [4-6]. But these methods are not capable
of reducing toxic level of the metals considerably.
Membrane separation technique is found as an easily
achievable and better technique for the separation of
toxic metals from wastewater which is used frequently
for the separation process [7]. Several membrane
based separation techniques including nanofltration
and reverse osmosis have been developed to remove
undesired constituents from aqueous streams [8-10].
These processes are carried out in homogeneous
solution. The usual processes such as reverse osmosis,
nanofltration seems to be highly expensive due the
requirement of higher pressures and high membrane
cost. Micellar enhanced ultrafltration (MEUF) can be
considered as a good alternative to remove heavy metals
from wastewater using micelle. It was frst introduced by
Scamehorn for the removal of both dissolved organic
compounds and heavy metal ions from waste stream
[3,7,11]. Number of investigations has been carried out for
the removal of metal ions from wastewater using MEUF
technique. The present paper attempts to review those
investigations. The infuence of various parameters such
Central European Journal of Chemistry
* E-mail: bag@ched.svnit.ac.in
** E-mail: amungray@yahoo.com
Department of Chemical Engineering,
Sardar Vallabhbhai National Institute of Technology, Surat 395007, India
Alka A. Mungray
*
, Shrirang V. Kulkarni, Arvind K. Mungray
**
Removal of heavy metals from wastewater using
micellar enhanced ultrafltration technique:
a review
Review Article
Abstract:
© Versita Sp. z o.o.
Received 2 July 2011; Accepted 19 October 2011
Keywords: Heavy metal ions • Micellar enhanced ultrafltration • Removal • Operating parameters • Rejection
Application of Micellar enhanced ultrafltration (MEUF) for the removal of different heavy metals has been reviewed. It is considered
an economical alternative available to the conventional membrane separation process, because it reduces the requirement of higher
pressure and high membrane costs. MEUF is a separation processes which uses surfactants and ultrafltration membranes to remove
multivalent ions from wastewater with high percent rejection using electrostatic attraction between metals and micelles.
This review seeks to defne the effect of the operating parameters, i.e., applied pressure, surfactant concentration,
feed temperature, metal ion concentration, feed fow rate, operating time etc. on the removal of metal ions. Emphasis is given
to the application of MEUF for the removal of single metal ions, multiple metal ions and different metals along with other organic
materials. Also, this review focuses on studies related to micelle formation, attraction between metal ions and micelles, and recovery
of surfactants for future research.
Cent. Eur. J. Chem. • 10(1) • 2012 • 27-46
DOI: 10.2478/s11532-011-0134-3
27