A team of scientists has developed a technique to use tea and banana waste to make non-toxic activated carbon that can be used for several purposes such as industrial pollution control, water purification, food and beverage processing, and odour removal.
The processing of tea generates a lot of waste, generally in the form of tea dust. They could be converted to useful substances. The structure of tea is particularly favourable for conversion to high-quality activated carbon. However, it normally involved the use of strong acid and bases, making the product toxic and hence unsuitable for most uses. A non-toxic method of conversion was needed to overcome this challenge.
Dr N. C. Talukdar, former Director, Institute of Advanced Study in Science and Technology (IASST), Guwahati, an autonomous institute of the Department of Science & Technology, Govt. of India and Dr Devasish Chowdhury, Associate Professor at the Insitute, used banana plant extract as an alternative activating agent for the preparation of activated carbon from tea wastes.
Oxygenated potassium compounds contained in the banana plant extract help in activating the carbon obtained from tea waste. An Indian patent has recently been granted for the new process. The process began with the drying of the banana peel. It was then burnt to make an ash out of it. The ash was further crushed and made into a fine powder. Subsequently, water was filtered through the ash powder using a clean cotton cloth and the final solution was used as the activating agent.
The main advantage of this process is that the starting materials, as well as activating agents, are waste materials. Also, no toxic material was used at all in the entire process. The most preferred banana was found to be Bheem Kol, which is an indigenous variety found only in Assam and parts of North East India. (India Science Wire)