Khalifa University of Science and Technology today announced a team of researchers has developed a graphene-sand hybrid material capable of absorbing pollutants from industrial wastewater, using two natural resources of great abundance in the UAE – sand and dates.
It involves attaching pollutants onto small particles that are then easily removed, they added.
While synthesizing graphene-sand adsorbents can be prohibitively expensive, the University researchers have turned to a previously unused resource – date syrup – to provide the carbon needed to produce the graphene. "The adsorbent can be used as an environmentally benign and scalable option for decontaminating wastewater, with the adsorption capacity far surpassing that of similar reported graphene-based adsorbents," the research found.
Led by Dr. Fawzi Banat, Professor, Chemical Engineering, the team includes Anjali Edathil, former Research Engineer, and Shaihroz Khan, visiting Research Assistant. The in-situ strategy used to produce the graphene-sand hybrid with date syrup is described in a paper published in Scientific Reports.
Dr. Banat’s team used pyrolysis – the process of chemically decomposing organic materials at high temperatures in the absence of oxygen – to decompose the date syrup. This triggers a change of chemical composition and the synthesis of a large volume of graphene material, that subsequently attaches to desert sand without the use of any external chemical agents. Moreover, graphene’s high surface area, combined with its versatile chemistry and highly water-repellent surface physical property, makes it an ideal adsorbent for removing pollutants.
Dr. Banat’s graphene-sand hybrid adsorbent was tested in the laboratory and showed remarkable efficiency in simultaneously removing both dye and heavy metals from multicomponent systems. The researchers concluded that their adsorbent had great potential as an exceptional material resource of water purification.
"This will undoubtedly open new avenues for the practicability of graphene to curb the existing water shortage," said Dr. Banat. "We hope our material will help in increasing water resources in the UAE, reducing energy consumption in wastewater treatment processes and be used to convert oily wastewaters from waste-to-commodity that can be used in applications such as industrial recycling and agriculture."