Байланысты: Сборник конф Фараби Әлемі 2023 химфак-печать
NITROGEN SELECTIVE REDUCTION OF NITRATES IN AQUEOUS ENVIRONMENT BY NANOCOMPOSITES APPLICATION Dyussenkulova B.Z 1,2 , Omirzakova A.T 2,3 Research supervisor: c.ch.s., senior teacher Vassilina G.K. 1,2 1 Al-Farabi Kazakh National University 2 Society of Petroleum Engineers International 3 Nazarbayev University balgyn111@gmail.com Nitrates are abundant contaminants in the groundwater’s composition. Natural nitrogen
balance has nitrates in less amounts which is negligible. Agricultural sectors usually use nitrates as
the source of fertilizers for vegetables and other types of flora. Excessive amounts of nitrates
washed off with rainwaters to the groundwater. Consequently, nitrogen species are exceeded than
allowed contamination levels for NO
3
-
—N is 10ppm when 0.3ppm for NO
2
-
—N due to
anthropogenic factors. Nearly all nitrate removal technologies for drinking water treatment rely on
biological denitrification else physicochemical separations such as ion exchange resins,
electrodialysis, reverse osmosis. Biological treatments are effective for nitrogen selective reduction
of nitrates; however, consume a lot of energy which was not satisfied to green ecological principles
and has high cost.
Nitrates remediation (nitrate to nitrogen) is preferable than nitrates valorization (nitrate to
ammonium). In this case, nitrates reduction by natural catalysts is applicable which will continue
about 30 days. Natural catalysts are based on support materials. Metals combination defines the
selectivity of obtaining products. Natural catalysts are different by their size scale such as macro,
submicron, nano, pico, etc. By decreasing of the size, the efficiency of the material increases.
In this work, natural catalyst was developed on the nano size. The developed nanocomposite
was In(6%)-Pt(1.5%)@BEA-MEG-3 which meant bimetallic catalysts on the surface of beta zeolite
which modified by monoethylene glycol. Synthesized BEA-MEG-3 differs than common beta
zeolite by the particle size and porosity including the zeta potential on the surface. Classical beta
zeolites have only micropores. Modified beta zeolite has mesopores too. The main novelty of the
conducted experiments is the catalytic reduction ability in 10 minutes instead of 30 days. Ammonia
selectivity was about 0.2% from the reduced nitrates amount. The difference of nitrogen species
gave the nitrogen gas amount. Then it could be concluded that In(6%)-Pt(1.5%)@BEA-MEG-3
reduced nitrates in 10 minutes with 99.8% of nitrogen selectivity.
The research work was financially supported by SC at MEHS RK as part of №AP14870836
“Development of Catalytic Wastewater Treatment Technology for Enhanced Removal of Nitrogen
Species”.
«Фараби Әлемі» атты студенттер мен жас ғалымдардың халықаралық конференциясы
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