ITDI Develops Solar Technology

To clean industrial-wastewater pollutants, Industrial Technology Development Institute (ITDI) of the Department of Science and Technology (DOST) has eliminated pesticides in contaminated water by developing a technology using sunlight and ordinary cosmetics ingredients.

Environmentalists in Bulacan welcome the development as it pose a possible solution to revive the Marilao, Meycauayan and Obando river system that the Blacksmith Institute, an international environment watchdog, has listed among the 30 dirtiest rivers in the world.

Beth Padilla, editorial and public affairs unit head of the Science and Technology Information Institute of the DOST, said in a statement that trial runs are onstream to treat wastewater contaminated with dyes used in handicraft industry, to help cottage-dyeing industries comply with strict regulations imposed by countries that rigorously monitor the environmental impact of exporters and their manufacturing activities.

Christopher Silverio, chief of the ITDI’s environmental division, explained: “Eventually, we intend to design and build a simple and inexpensive technology that runs using sunlight and, when that is not available, by using ultraviolet lamps as backup.”

The technology is called solar photocatalysis, a promising technique that uses sunlight and titanium dioxide, a nontoxic chemical commonly used as white pigment in paints and cosmetics to break down toxic and hard-to-remove pollutants.

Photocatalysis occurs when a relatively small amount of light-absorbing material, called photocatalyst, chemically reacts with the pollutants without itself being consumed; and in this case, the photocatalyst used is titanium dioxide.

The innovation is designed so that it will be cheap, easy to operate, and does not need filtration process that limits its commercial feasibility in the past. It simply involves passing of wastewater through glass tubes packed with titanium dioxide under sunlight. Solar photocatalysis is virtually unheard of domestically until ITDI researchers thought of ways to use sunlight to remove difficult-to-treat pollutants in wastewater. [via PIA]