Journal of Environmental Treatment Techniques
2020, Volume 8, Issue 3, Pages: 1144-1150
J. Environ. Treat. Tech.
ISSN: 2309-1185
Journal web link: http://www.jett.dormaj.com
Adsorption Studies on the Removal of Hexavalent
Chromium (Cr (VI)) from Aqueous Solution using
Black Gram Husk
Sunil Rajoriya*, Ahlaam Haquiqi, Bhawna Chauhan, Girish Tyagi*, Avdesh Singh Pundir*,
Ajay Kumar Jain, Divya Agarwal
Chemical Engineering Department, Meerut Institute of Engineering and Technology Meerut-250005
Received: 17/06/2020
Accepted: 09/07/2020
Published: 20/09/2020
Abstract
In the current work, black gram husk (BGH) as an effective adsorbent was used to remove the hexavalent chromium (Cr (VI)) from
aqueous solution in the batch mode. The characterization of adsorbent was done by Fourier transform infrared spectroscopy (FT-IR) to
identify the functional groups present on the surface of BGH. The study was done with synthetic wastewater having a Cr (VI)
concentration of 100 mg/L. Batch experiments were conducted to study the effects of various process parameters such as solution pH (1
–
7), adsorbent dosage (0.5 – 1.5 g/100 mL), initial Cr (VI) concentration (100 – 200 mg/L), and contact time (0 – 30 min) on the
efficiency of the adsorption process. The maximum % removal of Cr (VI) was 65.23% at the optimized set of process parameters i.e.
solution pH of 3, adsorbent dosage of 1 g/100 mL, contact time of 15 min. Freundlich and Langmuir adsorption isotherms were applied
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to investigate adsorption data, The observed experimental data fitted well to Langmuir isotherm (R = 0. 9804 and qmax = 9.19 mg/g).
The reusability study showed that BGH material is recyclable up to only one cycle with 45.19% Cr (VI) removal efficiency. The obtained
experimental results revealed that BGH as an efficient adsorbent may be used for the Cr (VI) removal from aqueous solutions.
Keywords: Black gram husk (BGH); Cr (VI); Adsorption; Reusability; Isotherms
Introduction1
cost, incomplete metal removal, large quantity of toxic sludge,
1
high energy requirement (16). However, Adsorption process
has been found to be suitable process to remove toxic metals
from wastewater using low cost adsorbents due to its high
efficiency, simple to operate, low cost, reusability of adsorbent
In recent years, the polluted water containing heavy metals
has led to serious issues due to the random discharge of heavy
metals in to the water bodies (1). Among the heavy metals,
chromium has the harmful effects on the aquatic environment
(
17). In the recent years, many authors have utilized the various
(
2). Chromium occurs in two stable oxidation states i.e.
trivalent chromium (Cr(III)) and hexavalent chromium
Cr(VI)) in aqueous solution. Cr (VI) compounds are 500 times
adsorbents towards the removal of chromium from wastewater
such as modified groundnut hull (2), paper mill sludge (3), tea
waste (5), neem leaves (18), husk of Bengal gram (19),
modified corn stalks (20), fertilizer industry waste material
(
more toxic as compared to Cr(III) because of its high water
solubility, carcinogenic, mutagenic properties (3). According
to the World Health Organization (WHO), the maximum
acceptable limit of hexavalent chromium concentration is 0.05
mg/L in wastewater (4). United States Environmental
Protection Agency (US EPA) has recommended the acceptable
level of Cr(VI) is 0.05 mg/L for potable water and is 0.1 mg/L
for inland surface waters (5). If hexavalent chromium is present
in water beyond the acceptable limit which causes skin
irritation resulting in ulcer formation, liver damage and
pulmonary congestion (6). Hence, it is necessary for industries
to decrease the Cr(VI) concentration from their wastewaters to
acceptable limit before discharging it into the aquatic
environment. There have been various processes implemented
to remove the chromium from industrial wastewater including
ion exchange (7,8), electro-dialysis (9), chemical coagulation
(
21), distillery sludge (22), coconut husk and palm pressed
fibers (23).
To the best of our knowledge, none study has been reported
in literature on the utilization of the husk of black gram for the
removal of chromium from industrial wastewater. Therefore, in
the present work, the possible use of the black gram husk for
the removal of chromium (VI) has been investigated for the
efficient removal of chromium (VI). The characterization of the
BGH adsorbent was done by Fourier transform infrared
spectroscopy (FTIR) analysis. Proximate analysis of the BGH
was also carried out. The influence of the different process
parameters like solution pH, adsorbent dosage, initial
chromium (VI) concentration and contact time was studied.
Reusability of the prepared adsorbent was also investigated in
order to check the efficiency of BGH. Besides, the adsorption
isotherms were also illustrated in the current work.
(
10), nanoparticles (11), membrane filtration (12),
electrochemical technologies (13), and adsorption (14, 15).
These processes have many disadvantages such as high capital
*
Corresponding authors: (a) Sunil Rajoriya, Chemical Engineering Department, Meerut Institute of Engineering and Technology
Meerut-250005, E-mail: sunilrajoriya@gmail.com. (b) Girish Tyagi, Chemical Engineering Department, Meerut Institute of Engineering
and Technology Meerut-250005, E-mail: girish.tyagi@miet.ac.in. (c) Avdesh Singh Pundir, Chemical Engineering Department, Meerut
Institute of Engineering and Technology Meerut-250005, E-mail: 2013rch9513@mnit.ac.in.
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