How to extract heavy metals from effluents released by industrial activity? Using garlic and onion peelings, a new study shows . These condiments absorb heavy metals so efficiently that they could become filters on an industrial scale.
Human activity does not create. These are present in the and are not harmful as such. However, the exploitation of natural , the metallurgical or mining industry and the use of in batteries encourage the of heavy elements into the environment. Which can then be harmful for humans. The of the oceans, for example has effects on human health. As well as .
The metallurgical and mining industries are the main sources of releases of heavy metals related to humans. In the, human activity causes the , , , and lead. How can the industry manage this ? Biotechnologists of the recently showed that the waste from the from the processing of ( Allium Cepa ) and the ( Allium sativum) could be used to decontaminate industrial effluents polluted with metals.
In the study published in the International Journal of Environment and Pollution () , researchers showed that onions and garlic absorb heavy metals from . For their experiments, they used condiment peels from onion treatment and conservation are effective decontamination materials. “This can make technology easy, affordable and with minimal maintenance for small and medium-sized businesses in developing countries, “ the researchers say.
Filtration of heavy metals with garlic and onions
By studying the influence of the acidity, the contact time, the temperature and the concentration of the different materials, the researchers optimized the conditions of realization of a heavy-metal filter on an industrial scale for the. According to their results, at 50 ° C, the efficiency of the cleaning process is largely dependent on pH. The process is optimal at pH 5. The onion then puts around half an hour to absorb the maximum of heavy metals.
This cleaning process seems to be very effective for lead. Thisis the most troublesome environmental pollutant. The Delhi University team extracted more than 10 mg of lead per gram of Allium from a test solution of 5 g / L . The condiment waste captures 70% of the in solution. Absorbed metals can then be released into a collection vessel using nitric .
Bioremediation is a clean solution for decontamination, but it is not often applicable on a large scale. However, using onion and garlic food waste, present in, can be an effective solution for medium-sized industries.