Tomsk, Russia – Sand, corals and even waste building materials can become extremely efficient sorbents for water purification from arsenic, if they are treated for this purpose. Scientists of Tomsk Polytechnic University have uncovered a new technology during experiments. In practice, they succeeded to purify at least 18,000 glasses of water with the help of 200 grams of sorbent from the available raw materials, the cost of which will be about 100 rubles for end consumers.
“Arsenic in drinking water is a huge problem for many countries across the world: India, China, USA, Argentina, Chile, Poland, Hungary and others. In Russia, arsenic containing regions are the Trans-Baikal, Khabarovsk, Perm, Stavropol, Magadan, Penza region, Dagestan, Tuva. Our technology allows any country to find the cheapest material to produce sorbents. This may be a Vietnamese sand, corals, in our region, one can use sand, waste from the production of bricks, aerated concrete”, explains the project’s scientific supervisor Mikhail Khaskelberg, engineer at the Institute of High Technology Physics.
Making simple materials work
According to him, for the experiments in the laboratory they use a solution in which the arsenic concentration was up to 50 times higher than the standards set by the World Health Organization: “Yes, scientists in different countries are studying the same corals and sand as sorbents. But we succeeded in making these simple materials to work very effectively, using simple and inexpensive processes in terms of future production.”
Thus, the scientists apply chemical adsorption resulting in contaminant deposition on the sorbent surface. By electrokinetic adsorption, the positively charged heavy metal ions are attracted to the negatively charged surface of a sorbent.
For private and industrial water
“This technology can be used for purification of water from private wells and industrial water,“ the scientist judges. „According to our calculations, one glass sorbent should be enough for at least 60-90 days, and if there is catastrophically much arsenic in water. Furthermore, our sorbent can be regenerated at least 10 times. Moreover, if a leading Bayer sorbent Bayoxide® E 33 on the market costs about $ 27 per kg; our technology can do sorbent by cost at $ 4-5 per kg. It is clear that it is not necessary ‚to fill in‘ a filter with only our sorbent. One needs only some part, the rest volume can be safely filled with any known sorbent – one gets a high quality filter with a wide range of applications.”
The technology is improved
The scientists at Tomsk Polytechnic University have already submitted an application for patenting the technology. They are also looking for Russian and foreign investors to introduce their development.
“Despite the fact that the purification of water using sorbents is not a pioneering discovery, the relevance of this subject is exceptional. Monthly top international journals published articles of serious scientists about the properties of the already known and some new materials. And this is understandable, the technology is improved, and problems are solved more elegantly. The basic idea is to develop the cheapest and most effective material. That is why the search is to be continued,” comments Mikhail Haskelberg.
Source: National Research Tomsk Polytechnic University (TPU © 2002-2016)