scholarly journals Magnetic Composite Sorbents for Trapping Heavy Metals from Liquid Waste and Their Immobilization in a Mineral-Like Matrix

Author(s):  
Yana Yu. Chernykh ◽  
Tatiana A. Vereshchagina ◽  
Elena V. Mazurova ◽  
Vladimir A. Parfenov ◽  
Leonid A. Solovyev ◽  
...  

Magnetic sorbents were prepared by addition of ferrospheres to zirconia-silica gel followed by thermal treatment at 500 °C. The ferrosphere narrow fraction E -0.063+0.050 mm from fly ash resulted from combustion of Ekibastuz coal was used as a magnetic component. The surface of magnetic composites was additionally functionalized by grafting of – POONa and – NH2 groups. Under equilibrium conditions sorption capacities of the sorbents with respect to Се3+ used as a U4+/Th4+ simulator and Pb2+ were measured by means of determination of sorption isotherms which were fitted by the Langmuir model. It was established that extraction of Се3+ and Pb2+ from aqueous solutions is characterized by distribution coefficients of 104–106 ml/g. Temperature conditions for solid-phase crystallization of the sorbents resulting in polyphase systems with the content of zircon phase of 50 wt. % were found

Author(s):  
Tatiana A. Vereshchagina ◽  
Ekaterina А. Kutikhina ◽  
Yana Yu. Chernykh ◽  
Elena V. Fomenko ◽  
Elena V. Mazurova ◽  
...  

The influence of hydrothermal conditions on synthesis of analcime and a composite material ZrO2- analcime as well as zirconomolybdate coverings with ion exchange properties was studied using narrow fractions of aluminosilicate microspheres with a high content of a glass phase (91-95 wt. %). The possibility to synthesize ZrO2-analcime composites of narrow particle size distributions with maximum of about 40 μm and 6 μm under hydrothermal treatment at 150 °С was demonstrated starting from microspheres with Si/Al=2.7 and applying different regimes of a reaction mixture agitation. A microsphere material of a “core-shell” type such as ZrMo2O7(OH)2(H2O)2@(SiO2-Al2O3)glass with the nanostructured covering was prepared. Sorption properties of the materials regarding Nd3+, Sr2+ and Cs+ were studied under equilibrium conditions by means of determination of sorption isotherms and their fitting by the Langmuir model. Sorption parameters were determined including distribution coefficients which reach the values of 104−105 mL/g


2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Michał Sadowski ◽  
Piotr Anielak ◽  
Wojciech M. Wolf

The coagulation process is used as the first step for the chemical treatment of liquid waste. Resulting wet sludge is treated with coagulants or polyelectrolytes to improve dewatering characteristics of its so-called conditioning. The coagulants such as aluminum sulphate or polyaluminum chloride (Al2Cln(OH)6−n) are widely used for dairy wastewater treatment systems. The pretreatment dairy sludge can be applied in agriculture as fertilizer containing valuable nutrients. Hence, a simple, cost effective, and rapid method for the determination of aluminum content in the sludge is essential for calculation of the appropriate coagulant dose at the sludge pretreatment process. In this paper either colorimetric or atomic absorption spectrometric methods as applied for the determination of aluminum concentration in the dairy wastewater are compared. For colorimetric method, the optimum experimental conditions such as pH, reaction time, and concentration of other ions in the sample were determined. The sorption isotherms of aluminum on the activated sludge were determined for diverse aluminum species.


2016 ◽  
pp. 137-142
Author(s):  
V.O. Benyuk ◽  
◽  
V.M. Goncharenko ◽  
T.R. Nykoniuk ◽  
◽  
...  

The objective: to еxplore the relationship between the activity of endometrial proliferation and the state of the local immune response in the uterus in the conditions berprestasi process. Patients and methods. Examined 228 women of reproductive and perimenopausal age with endometrial pathology using ultrasound and then performing hysteroresectoscopy. Determination of the concentrations of the cytokines IL-1, IL-2, IL-6 and TNF was performed by solid phase ELISA. Results. Found a trend that confirms the loss of sensitivity to hormones at the stage of malignancy of the endometrium and can be used as diagnostic determinants in determining the nature of intrauterine pathology and criterion of the effectiveness of conservative therapy. Conclusion. Improving etiopatogenetice approach to the therapy of hyperplastic proce.sses of endometrium with determination of receptor phenotype of the endometrium is a research direction in modern gynecology, which will help to improve the results of treatment and prevention of intrauterine pathology. Key words: endometrial hyperplasia,the receptors for progesterone and estrogen, immunohistochemical method.


2019 ◽  
Vol 85 (2) ◽  
pp. 12-16
Author(s):  
I. V. Saunina ◽  
E. N. Gribanov ◽  
E. R. Oskotskaya

The sorption of Hg (II), Cd (II), and As (III) by natural aluminosilicate is studied. It is shown that the mineral absorbs those toxicants in a rather wide pH range, quantitative extraction of analytes being achieved in a neutral or close to neutral medium (pH values range within 7.0 - 8.0; 6.3 - 7.5; 7.4 - 8.5 for Hg (II), As (III), and Cd (II), respectively). The effect of the time of phase contact on the degree of extraction of elements is shown. The sorption capacity of the mineral in optimal conditions of the medium acidity (0.06 mmol/g for mercury, 0.31 mmol/g for cadmium, and 0.52 mmol/g for arsenic) is determined. The distribution coefficients attain values of aboutnX 103-nX 104. A new combined method for determination of Hg (II), Cd (II), and As (III) in natural and waste water is developed and tested. The method consists in a preliminary group sorption concentration of the analytes by aluminosilicate, desorption of the analytes from the surface of the mineral and their subsequent atomic absorption determination. The correctness of the method is verified in analysis of spiked samples. The method is easy to use and exhibits high sensitivity, reproducibility and accuracy of analyte determination. The relative standard deviation does not exceed 0.13. Economic availability and possibility of using domestic sorption materials are the important advantages of the proposed procedure which can be used in the practice of laboratories monitoring the quality and safety of environmental objects.


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