We stack it, some hoard it and mostly it ends up as pulp or packaging material. Now, the discarded rag of a newspaper could be reincarnated as a highly sophisticated form of cleansing agent. Japanese scientists are developing a process wherein a residue obtained from old newspapers could be used to extract precious metals from discarded e-waste.
E-Waste is now a necessary evil. And its proportion is going up with each passing day as the world gets increasingly digitized. Generation of e-waste is not as much a problem as its disposal. That is where newer technologies are concentrating. When it comes to disposing off e-waste even 21st century’s technology hasn’t managed to reach satisfactory levels of expectations. Every recycling plant is basically a shredder. Masses of junked computers and electronic products are crushed under giant pulverizers and the extract is mined for precious metals like Gold, Silver, Nickel, Copper and Platinum. But this mining and extraction process is crude at best and the high processing costs inherent in any recycling effort discourages wide adoption of the practice.
According to the U.S. Environmental Protection Agency, less than 20 percent of discarded electronics are currently recycled in the U.S. Most of the waste is shipped across the seas to Asian countries where unsafe recycling practices are a danger to not only the workers on the ground but also to the environment. Third world countries concentrate on the metals but discard the useless plastic to be burnt. This releases toxic dioxin clouds into the atmosphere adding to the pollution woes.
The nascent e-waste recycling industry would surely welcome this development from the Saga University in Japan. Katsutoshi Inoue and his colleagues have developed a new gel compound using discarded newsprint as a base. This gel like compound can be used to treat e-waste for its precious metals without damaging the environment. The innovation involved the treatment of crushed and washed paper pulp with chlorine. The chlorinated paper was then treated with a mixture of dimethylamine (DMA) and formaldehyde to form what they call a DMA-paper gel. The paper gel is then dried into powdery substance. The gel was tested on a ‘liquor’ of industrial waste metals dissolved in hydrochloric acid. The gel surprisingly proved to be highly selective in the metals it adsorbed. It took up over 90% of the gold, platinum and palladium, but almost negligible quantities of copper, zinc and iron. Though the exact science is still unclear, it seems that that the binding structure of newsprint is responsible for the selective assimilation of the metals. The shapeless structure of cellulose in the paper also gives the gel a high relative capacity by weight to absorb the metals. One kilogram of gel can hold 906 grams of gold.
Of all the research done so far on recycling e-waste this development from Japan is the most promising yet. Prepared from discarded newsprint using an inexpensive process, the gel’s high absorption capacity makes it a wonderful new age material. The distance from the laboratory to the real world is often fraught with many hurdles and Katsutoshi Inoue’s team might have to take them in their stride but it is a promising beginning for the fledgling and the still unattractive field of e-waste management.
