Proceedings of CUChE Alumni Symposium 2022
On Circular Economy on Sustainable Basis: The Role of Chemical Engineers
CUChEAA ISBN: 978-81-954649-1-3
December 2022 P a g e | 75 Volume 2, Issue 1
Prospect of electrochemical process-induced separation techniques to redefine waste-water as
the resources A journey towards circular economy
Pallab Kumar Bairagi
Ordnance Factory Nalanda, Department of Defence Production, Ministry of Defence, Rajgir, Bihar, India
Telephone: 06112-257-121 Extn. 4010/11
Exponential population growth, rapid industrialization and urban expansion in 20
and 21
centuries have adverse effect
on natural resources and living beings because of industrial, municipal and agro-industrial waste generation in billion tons
per year. Efficiency of these resources can be enhanced by proper treatment of contaminated natural resources. Therefore,
to control the natural resources sacristy, to reduce anthropogenic activities on ecosystem and to minimize climate change,
efficient treatment and separation techniques need to be developed or chosen carefully. Water is one of those badly
affected natural resources, and therefore, treatment of waste-water is a major concern especially in India. However, waste-
water can be considered for mining the valuable precursors and bioactive substances present in it which needs highly
selective, fast, and efficient separation processes. The process must involve materials with high selectivity to capture target
compounds/molecules/species from complex systems or complex fluids. Herein, this review describes an outline of
different separation techniques used for the separation and treatment of precursors and bioactive substances present in
waste-water with a focus on electrochemical techniques. The review describes the recovery of nitrogen- and phosphorus-
nutrients as the case study for their important role in natural, semi-natural and artificial systems where nitrogen and
phosphorus present as several species, mainly, ammonia and nitrates. Different selective materials are also discussed for
their applications in selective separation. Moreover, this perspective provides an idea of the fast, efficient, and resource-
oriented separation techniques integrated with electrochemical processes, which will play a crucial role to make waste-
water as the useful resources for the nutrients-recovery and to enable the target molecule-specific circular economies in the
next few decades. This review may pave a way to develop different selective materials and separation techniques which
can integrate circular economy (CE), bio-economy and green-economy towards a total economy to redefine different waste
materials as the resources of different nutrients, bioactive substances, and microorganisms.
Keywords: natural resources, electrochemical processes, waste-water, bioactive substances, circular economy (CE).
1. Introduction
A special format of the periodic table was presented by
the European Chemical Society for celebrating 150
birthday of Mendeleev’s periodic table on 2019 to
describe and indicate the scarcity of elements and
subsequent potential threat [1, 2]. Increasing rate of
population growth in the urban areas and rapid
industrialization in 20
and 21
centuries have adverse
impact on natural resources and living beings by
generating billion tons of industrial, municipal, and agro-
industrial waste annually [3]. The European Chemical
Society emphasized that our precious resources must be
used carefully in the upcoming years with a special effort
on minimizing the waste generation and partial recycling;
failing which, a few natural elements which are highly
important and critical for our surrounding world may be
diminished because of their limited existence, area of
location, or our inability to recycle those elements
properly [4, 5]. Development of new techniques or
modification of existing methods and introduction of
those for taking remedial action through post-utilization
recycling of resources and recovery of precious elements
from the waste generated may enable the use of these
resources, elements and materials in a circular way which
is the key to conserve these precious natural elements [6,