Coffee Husk as Adsorbent for The Heavy Metals (Cr And Pb) Removal from Synthetic Wastewater
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Date
2019-05
Authors
Journal Title
Journal ISSN
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Publisher
Addis Ababa University
Abstract
Heavy metal contamination of water is a serious threat to the ecosystem. Many industries
such as electroplating, metal plating, mining operation, and tanneries release wastewaters
containing heavy metals into the environment. The objective of the study was to investigate
the efficiency of coffee husk for the removal of heavy metals
(chromium. and Lead) from
synthetic wastewater. Adsorbent was prepared from coffee husk and treated with 2%
formaldehyde solution in order to reduce biodegradation of organic compounds and avoid
mould formation during continuous sorption. It’s surface functional groups were analyzed
using fourier transform infrared spectroscopy and the major peaks were observed at 3444
cm
-1
-1
,3438cm
-1
and 3432cm
which may representing bonded –OH groups rather than –NH
group. Sorption studies were conducted in a continuous system. The sorption efficiency and
adsorption capacity were studied as a function of adsorbent dose ,pH and flow rate of
optimum results were found to be 99.8% at 30g, 3 and 5ml/min and 99.45% at 30g, 12 and
5ml/min which are the optimal conditions for Cr
(VI
) and Pb(II
) respectively. The Sorption
performance was improved as pH and flow rate decreased and adsorbent dose increased for
Cr
(VI
) and pH, adsorbent dose increased and flow rate decreased for Pb(II
). The highest
adsorption capacity were also found to be 0.18806mg/g and 0.18mg/g at distinct pH=3 & 7.5
values for Cr
(VI
) and Pb(II
) respectively and flow rate of 5ml/min.. Generally the study
showed that coffee husk can be used as a good adsorbent for the removal of chromium and
lead from synthetic waste water.
Description
Keywords
Sorption, coffee husk, Chromium, Lead, wastewater