CC BY
5
практика образования в современном мире Материалы VIII Международной научной конференции. 2015. С. 22-26.
3. Куправа А.Э. Вопросы традиционной культуры абхазов // Традиционная культура абхазов - Апсуара. РУП «Дом печати». 2014. C. 2-48.
УДК 628.16.081.3
Silaycheva М. V. graduate student of 2 courses faculty of environmental safety, information and process security Kazan national research technological university
Russia, Kazan
Stepanova S. V., Ph.D. in Engineering Science, associate professor associate professor of Engineering Ecology department Kazan national research technological university
Russia, Kazan
BIOSORPTION TREATMENT OF POLLUTED WATER FROM IRON (III)
IONS USING MAPLE TREE WASTE
The first aim of article is obtaining of kinetic curves of iron ions (III) on to maple tree waste at different temperatures. The second aim is determination of minimum residual concentration of iron ions (III), maximum sorption capacity and the most effective process temperature.
Keywords: biosorption treatment, iron ions (III), maple tree waste, temperature, kinetic curves.
Today factories of the world produce a huge amount of wastewater. What is wastewater? It is the water, obtained after cooling, washing of raw material and different reactional solutions. Wastewaters are polluted with heavy metals, oil products, acids and alkalis, mineral impurities, etc.
Heavy metals are among the most dangerous industrial pollutants. Industrial effluents contain such heavy metals as iron, nickel, zinc, lead, cadmium, chromium and others. So my research is related to treatment of water bodies from iron ions, because domestic water from underground sources has a lot of these ions in its composition.
Elevated levels of iron in water (above 0,3 mg/L) as bicarbonates, sulfates, chlorides give unpleasant red-brown color, impair the taste, lead the development of iron bacteria, the formation of deposits in the tubes. Also iron ions can affect to people's health. People may receive following health problems: dizziness, kidney failure, violation of the intestinal mucosa [1].
There are many ways of water purification from metal ions. One of them is biosorption. Biosorption is the removal of materials (compounds, metal ions, etc.) by inactive, non-living biomass (materials of biological origin) due to "high attractive forces" present between the biomass and metal ions. It means that components of maple tree waste can attach metal ions from waters.
The examples of biomass, used as biosorbents, can be algae, sea-weeds, coconut shell, tea waste, rice husk, mango and other leaves, etc. Maple leaves are used as biosorbents in this scientific work. The main components of these leaves are cellulose, lignin, tannins, sugars as well as other compounds carrying different functional groups like carboxyl, hydroxyl, carbonyl, methoxy, et al. These groups, present in the cell wall, make it possible removal of metal ions from waters, because of formation of complex compounds on the surface or in the pores of biosorbent.
In comparison with conventional sorbents, such as activated carbon, silica gel and zeolites, natural biosorbents have high efficiency and high biosorption capacity too. But it also has cost-effectiveness and renewability. These parameters are important for making studied materials as economical alter-natives for metal removal and waste remediation [2].
The aim of this research is to investigate the possibility of polluted water treatment from iron ions (III). Sorption process was carried out at the temperature range: 303-368 K for iron (III).
During the experiment, 100 cm3 of water polluted with iron chloride with concentration of iron ions 100 mg/L was added to each of the five flasks, where we also added 1 g of ground leaves.
Then contents of flasks were heated in water-bath at different temperatures. Every 10, 30, 60, 75 and 90 minutes the content of each subsequent flask was cooled and filtered, and then we measured residual concentration of iron ions by photocolorimetric method.
The essence of this method is measuring of filtered sample's optical density with respect to the blank solution. The blank solution is distilled water. Then the values of optical density were converted into values of residual concentration of iron ions with calibration schedule [3].
We received dependence of residual iron ions concentration on contact time in minutes. Then we turned the values of residual concentration of iron ions into the values of sorption capacity. The dependence of iron (III) sorption capacity on contact time is shown in Figure 1.
^12
-**-368 К
-Q-313K
-л-353К
-<^303 К
0
20
40 60
Time (min)
80
100
Figure 1 - Kinetic curves of iron ions (III) sorption at different temperatures In the case of maple leaves, the sorption capacity of iron (III) increases rapidly in the initial stage (up to 20 min) but becomes slow in the later stages at the attainment of equilibrium [4]. The sorption capacity, residual concentration of iron ions and equilibrium time are shown in Table 1.
Table 1 - The values of sorption capacity, residual concentration of iron ions (III) and equilibrium time._
Temperature, K Sorption capacity, mg/g Residual concentration of iron ions (III), mg/L Equilibrium time, min
303 8,847 11,53 It does not come
313 8,984 10,16 79
353 9,075 9,25 49
368 9,389 6,11 34
In this way, with rising of temperature the sorption capacity is increased while the residual concentration of iron ions (III) and equilibrium time are decreased. So maximum of sorption capacity is equal to 9,389 mg/g at the temperature of 368 K and the minimum residual concentration of iron ions is equal to 6,11 mg/L at the same temperature. Consequently, the sorption process should be carried out at the temperature of 368 K.
According to the requirements, the MPC (Maximum Permissible Concentration) of iron ions in water is 0,3 mg/L. During our experiment, iron ions (III) concentration is equal to 6,11 mg/L, so biosorption method can't be used for basic treatment, but for sure, it will be used for pre-treatment of water.
References:
1. Елизарова Т.В., Михайлова Л.А. Гигиена питьевой воды. Уч. пособие. -Чита: ЧГМА, 2007. - 63 с.
2. Farooq U., Kozinski J.A., Khan M.A., Athar M. Biosorption of heavy metal ions using wheat based biosorbents - A review of the recent literature // Bioresource Technology. - 2010. - Vol. 101. - № 14. - P. 5043-5053.
3. ПНД Ф 14.1:2:4.50-96. Количественный химический анализ вод. Методика измерений массовой концентрации общего железа в питьевых, поверхностных и сточных водах фотометрическим методом с сульфосалициловой кислотой. - М.: ФБУ «ФЦАО», 2011. - 17 с.
4. Acheampong M., Pereira J., Meulepas R., Lens P. Kinetics modelling of Cu(II) bio-sorption on to coconut shell and Moringa oleifera seeds from tropical regions // Environmental Technology. - 2012. - Vol. 33. - № 4. - P. 409-417.
