Nanoclay for Micropollutant Removal in Wastewater-Effective Alternative?

Abstract:

The effluent of wastewater treatment plants (WWTPs) is an important source of priority substances and is, therefore, one of the bottlenecks in achieving the European Water Framework Directive (WFD) objectives. At various locations in the Netherlands, standard for priority substances are exceeded. The current concern regarding the cost and treatment method of these micropollutants in receiving waters may call for new approaches in wastewater treatment. In this study, a new treatment alternative is developed to remove micropollutant and wastewater parameter effectively and in a more cost effective way. A potential solution is the used of clay coupled with biodegradable polymer flocculants. Clay is naturally abundant and relatively inexpensive compared to currently conventional used adsorbent which can also act as coagulants. Experimental studies were carried out with four different nanoclay to select the best nanoclay for further optimisation. The atrazine removal percentage archived is in the range of 10-99% based on the nanoclay concentration of 0.01-50 g/L. Optimisation of best nanoclay performer leads towards atrazine reduction of >99% with dosage of 0.1 g/L. The best and underperformed nanoclay then tested in other experiments with the addition of cationic starch flocculants. In this experiment, the addition of polymer increased the atrazine removal for the underperformer nanoclay to 46% with only 0.01 g/L clay dosages. This new approach in dealing with both micropollutant and wastewater parameter is promising and might help in reducing the compound concentration and the operational cost. However, further analysis and optimisation is required before any conclusion can be made.

• Periodical: Advanced Materials Research (Volume 1024)
• Pages: 11-14
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1024.11
• Online since: August 2014
• Authors: Mohamad Faiz Mohd Amin*, S.G.J. Heijman, L.C. Rietveld
• Keywords: Atrazine, Flocculations, Micropollutant, Nanoclay, Polymer

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