Ультразвук широко используют в пробоподготовке, в том числе для интенсификации фильтрационных, экстракционных и сорбционных процессов.Ранее нами предложен способ сорбционного концентрирования ионов металлов с использованием ультразвуковых суспензионных (УЗС) колонок [1-2], позволяющий удерживать в потоке жидкости суспензию мелкозернистого сорбента без применения фильтров.Ультразвуковое воздействие, создаваемое в колонках, влияет также на кинетику сорбции веществ за счет возникающих микротурбулентных акустических течений, которые создают условия для ускоренного протекания сорбции благодаря интенсификации массопереноса в системе сорбат-сорбент.В настоящей работе продемонстрирована возможность использования УЗС колонок (рис.)для повышения эффективности извлечения платиновых металлов на стадиях сорбции из многокомпонентных хлоридных растворов и последующей десорбции с получением индивидуальных растворов целевых компонентов.В качестве сорбента использовали силикагель Kromasil Sil, состоящий из идеально сферических частиц определенного размера (5 мкм), модифицированный фосфониевой ионной жидкостью Cyphos IL 101.Определены оптимальные условия для селективного выделения платины (IV) и палладия (II) в УЗС колонке: 0.1-1 M HCl, 10-60 г/л Cl -, содержание ионной жидкости 0.3 ммоль/г, скорость пропускания раствора 0.5 мл/мин, масса сорбента 0,02 г, интенсивность ультразвукового излучения 10 5 Вт/м 2 .Известно, что элюирование платиновых металлов обычно затруднено.Нами показано, что в условиях УЗС колонки существенно увеличивается эффективность десорбции платиновых металлов.Так, при использовании в качестве элюента перхлората натрия (0.5 М) и скорости пропускания раствора 0.2 мл/мин обеспечивается количественное извлечение металлов из фазы сорбента.Разработанная методика сорбционного концентрирования платины и палладия апробирована

The properties of a Diasorb-130-IDK sorbent based on silica gel with a grain size of about 6 µm were studied in order to choose conditions for the separation of the rare-earth elements from the samples of natural wine and their subsequent determination by inductively coupled plasma mass spectrometry. The possibility of the quantitative separation of the elements with the use of an ultrasonic flow suspension column was demonstrated. The results were compared with data obtained with the use of other sample preparation methods. A procedure was proposed for the determination of the rare-earth elements and yttrium in the samples of wines.

This paper reports the application of online membrane filtration with UV visible absorption as a mode of polydispersed substances detection for poly(acryloyl morpholine-co-2-acrylamido-2-methyl-1-propane sulfonic acid), poly[2-acrylamido-2-methyl-1-propane sulfonic acid-co-(3-acryloylamidopropyl) trimethylammonium nitrate), and poly(vinyl alcohol-co-crotonic acid) 10 % of crotonic acid which can be used in medicine and technology. The mass balance in all the cases was not below 100 ± 7 %. The calibration curve are linear at lopt. 245, 230, and 220 nm in the interval 0.1–4.0 mg/mL, 0.2–3.0 mg/mL and 0.2–6.0 mg/mL, respectively. It was also used the combination of microfiltration, MF, and gel permeation chromatography, GPC to provide more complete information about the molecular weight distribution of the obtained fractions.

This paper reports the results of the investigations of 2006–2007 on the distribution and migration forms of artificial radionuclides and chemical elements in the Ob-Irtysh water system. Three regions were studied. One of them is a local segment of the Ob River upstream from the confluence with the Irtysh River; its investigation allowed us to estimate the general radioecological state of the aquatic environment affected by the activity of the Tomsk 7 plant. The second region is a local segment of the Irtysh River upstream from its confluence with the Ob River, where the influence of emissions from the NPO Mayak could be estimated. The third region is the water area of the Ob River after its confluence with the Irtysh River. It characterizes the real level of radioactive and chemical contamination of the middle reaches of the Ob River.

To determine the molecular weight distribution of natural polydisperse compounds (peat humic acids) and synthetic substituted polyvinyls, membrane filtration, gel-permeation chromatography, and spectrophotometric determination procedures were developed. The determination limit of polyvinyls was 0.1–0.2 mg/mL. The absorbance of polyvinyl solutions was a linear function of the concentration over the range 0.1–6.0 mg/mL. It was found that the size-fraction distributions of both humic substances and substituted polyvinyls depended not only on the molecular weight, but also the molecular conformation.

Reinforced track membranes are used for the first time to study element distribution between particles of various sizes and other water components. The properties of the reinforced track membranes are considered. Factors affecting the quality of water in the Volga River in the region of the water intake of the city of Dubna in the Moscow region and potable water in various districts of the city in are characterized by the fractional composition of macro- and microcomponent.

Distribution of Cs, Sr, and Pu nuclides between suspended matter and the aqueous phase and the features of interaction of these radionuclides with dissolved organic matter are studied, to gain a better insight into the radionuclide behavior in the Ob and Yenisei estuaries and adjacent Kara Sea. For radionuclide speciation, the experimental study included determination of the radionuclide activities in aqueous solutions after filtration and ultrafiltration of large-volume water samples and membrane fractionation of small-volume water samples by passing the solution through a cartridge with filters of regularly decreasing pore size followed by mass-spectrometric determination of elements. In the water-soluble fraction, the 137Cs activity increases with increasing salinity, whereas that of 90Sr decreases, which can be attributed to the differences in the physicochemical behavior of the radionuclides in solutions and also to the effect of contamination sources. In seawater, suspended material can retain 1-10% of 137Cs and 90Sr. In the estuarine zones, these values can be 20-40%. More than 50% of 90Sr and 239,240Pu are associated with dissolved organic matter. In saline water this effect is less pronounced.

The possibility of extraction and fractionation of humic acid (HA) in the aqueous biphasic systems (ABS) was shown for the first time. The 10% PEG–10% (NH4)2SO4–H2O and 5% PEG–7.5% dextran (or dextran sulphate, sodium salt)–H2O systems were used. HA originated from peat, soddy-podzolic soil and chernozem were studied. The distribution coefficients were measured for HA of different origin, size of the molecules, molecular weights (MW) of the polymers and pH of the system. The PEG–(NH4)2SO4–H2O system was found to be better for preconcentration and isolation of HA, whereas the PEG–dextran–H2O system is preferable for HA fractionation. The extractability of HA in ABS increases with increasing the MW of HA molecules. Peat HA are extracted in ABS with higher distribution coefficients compared with chernozem and soddy-podzolic soil HA. It is consistent with higher hydrophobicity of peat HA revealed by hydrophobic interaction chromatography. ABS are promising for HA separation into fractions that differ in their hydrophobic/hydrophilic properties as well as for comparing HA of different origin by their relative hydrophobicity.