(215w) Biofiltration of Cu (II) Using Acclimated Mixed Culture

Heavy metal pollution by industrial activities and technological development is posing significant threats to the environment and public health because of its toxicity, non-biodegradability and bio-accumulation [1, 2]. The threat related to the disposal of heavy metal ions would increase significantly in the future years. Cupric compounds find many industrial applications such as in manufacturing of pesticides and fertilizers, mining, petroleum refineries, textile industries,synthetic rubber manufacturing ,preparation of catalysts etc. Copper, in lower concentration is not harmful to health (1mg/L). High dose of copper is harmful to all living organisms. It causes headache, vomiting, dizziness, nausea, damage to liver and kidneys and damage to marine organisms. A lot of physicochemical strategies, such as filtration, chemical precipitation, electrochemical treatment, oxidation/reduction, ion exchange, membrane technology, reverse osmosis, and evaporation recovery, have been developed for removing heavy metals from the polluted water [3]. However, most of them appear to be expensive, low efficient and labour intensive [4]. The main disadvantage associated with the above mentioned methods are the production of secondary pollutant obtained while separation of toxic metal compounds. In case of reverse osmosis the membrane has to be disposed when it is exhausted. So in all these methods the secondary pollutants produced have to be treated before dumping it to the environment. Considering these disadvantages, a new technique called bioremediation has been proposed for the removal of heavy metals from waste water. This can be solved by using biofiltration. Biofiltration uses a natural process of removing heavy metal ions from waste water using microorganisms. Microorganisms attach to the packing material in the form of biofilm. It  acts as a catalyst and is able to utilize heavy metal compounds as a source of available carbon for further cell growth. This technique is environment friendly as it does not produce any secondary pollutants. Biofiltration does not require external energy and utilizes the capacity of microorganisms to transform the toxic heavy metals. The isolation of microorganisms that can sustain heavy metals and the understanding of the mechanisms can contribute to the development of improved detoxification processes.

The present study deals with the biofiltration of Cu(II) from aqueous solutions using an acclimated mixed culture developed from activated sludge. The biodegradation studies are conducted for 40 mg/L initial Cu(II) concentrations with different inlet concentrations such as 10, 20 and 30 mL/min. The final copper concentration is measured using Atomic Absorption Spectrophotomer. A maximum of 97% removal copper is achieved on the 23^rd day of operation of the biofilter column for 30 mL/min of inlet flow rate of copper solution. The CFU analysis showed a decreasing trend of growth from top to down of the column.

References:

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