The paper presents the results of a study of the porous structure and sorption characteristics of technogenic foam silicate obtained in the process of complex processing of waste ore raw materials and modified in the process of thermochemical treatment in the gas phase of hydrocarbons. The parameters of thermochemical modification of the surface of foam silicate to obtain an oleophilic adsorbent for the removing of petroleum products from aqueous media, as well as the modes of its regeneration, have been determined. It has been established that the degree of extraction of petroleum products from water by the resulting adsorbent under static conditions is 99.8

A micropaleontological study of the oldest sediments of the Cenozoic sedimentary cover of the Sea of Japan, found on the Yamato Rise, allowed us to identify the palynological assemblage of the late Paleocene age (59.2–56.0 Ma) and refine the age of the host sediments. The findings of exclusively marine microfossils (diatoms and silicoflagellates) in these sediments, the high content of geochemical indicators of paleosalinity (B, B/Ga) in them, the chemical composition of autigenic minerals, as well as the presence of organic remains close to seaweed in them, prove the marine genesis of these deposits. It is assumed that sedimentation occurred on the periphery of the epicontinental shallow sea basin under climate conditions close to subtropical.

The paper analyzes data on the removal of arsenic by sorption methods using materials that have prospects for large-scale application in water treatment. These materials include transition metal oxides in the micro- and nano-dimensional form, including those in the composition of composite materials with inorganic matrices, or hybrid sorbents in the composition with polymer resins or natural biopolymers. Examples of the use of composite (hybrid) sorbents for the removal of arsenic from solutions with low concentrations (at the level of MPC) are given. The objective of this article was to sum the up-to-date information about the most important features of chitosan-containing and chitosan-carbon materials we developed in view their use in arsenic removal processes at low concentrations to concentrations that meet WHO requirements. The paper presents data on the sorption properties of Mo-containing activated carbon fibers and chitosan-carbon composite materials towards arsenic (V) when it is extracted from bidistilled and tap water under static and dynamic conditions. The factors of the different behavior of the sorbents depending on the form of a biopolymer deposited on the fiber and the stability of the sorbents during the sorption of arsenic are discussed.

The paper presents the results of multidisciplinary studies in the carbonate–barite mineralization area revealed on the western slope of the Kuril deep-water basin in the Sea of Okhotsk. Findings of carbonate concretions and barite in different age (Miocene–Holocene) deposits indicate that the bottom of this area hosted a long-lived center of gas–fluid emanations over several million years. The age of the host deposits was determined based on the diatom analysis: the oldest age corresponds to the Late Miocene (7.67‒6.57 Ma). The carbonate–barite mineralization originated due to the migration of hydrocarbon (mainly methane) and Ba-containing gas–fluid flows derived from both near-surface reservoirs and deep sources. The flows were most likely associated with mud volcanism. Hydrocarbon gases in pore fluids of the sediment are enriched in heavy methane homologues, while carbonate concretions are characterized by a heavier oxygen isotope composition. The Sr isotope composition (87Sr/86Sr) is significantly lower (0.708581) compared to the water of modern sea basins, which may also indicate the deep nature of fluids. Modern activity is expressed in the episodic manifestation of gas flows as strong hydroacoustic anomalies in the water core.

Sodium and potassium aluminosilicates samples are synthesized from solutions formed via the alkaline hydrolysis of rice straw. The fabricated samples are characterized by means of X-ray diffraction analysis and IR-spectroscopy, and their elemental composition, particle morphology, specific surface area, and thermal properties are determined. The sorption properties of the synthesized aluminosilicates with respect to Cs+ ions are investigated under static conditions. Kinetic curves and sorption isotherms are provided and a sorption kinetic model is described.

The possibilities of using chitosan and its composites with transition metal oxides for arsenic removal from solutions with low concentrations are discussed. Methods for the formation of composite sorbents based on chitosan and molybdenum in a composition with a carbon fiber providing improved physical and chemical properties with respect to the recovered component are considered. The sorption properties of the obtained materials under dynamic conditions for the purification of solutions from arsenic are compared. It is shown that the preliminary modification of the carbon fiber with chitosan by ionic gelation using sulfate ion and then by adsorption with molybdate ion leads to the production of an efficient sorption material that provides the purification of 1600 column volumes of an arsenic solution at an initial concentration of 105 μg L –1 to a maximum permissible concentration of 50 μg L –1 . The calculation methods show that the gel ability of sulfate and molybdate ions is approximately the same.

Variations in mercury contents in marine sediments have implications for hydrothermal activity, paleoclimate, depositional environments, and primary bioproduction. Mercury contents reach 148 ppb in hydrogenic ferromanganese crusts on flat-topped seamounts. Such crusts, with up to 4120 ppb Hg, were dredged from the slopes of Seth Guyot in the western Marcus-Wake Seamounts in 1982, during the 13th cruise of RV Vulkanolog. The Seth Fe-Mn crusts are of the same origin as hydrogenic Co-rich ferromanganese deposits from seamounts in other oceanic regions. Mercury accumulated in the Cenozoic as Fe-Mn oxyhydroxides in the crusts adsorbed Hg from bottom water. The process was especially rapid during the Pliocene volcano-tectonic rejuvenated stage. (C) 2018, V.S. Sobolev IGM, Siberian Branch of the RAS. Published by Elsevier B.V. All rights reserved.

The REE composition of modern mineral–organic associations in the sulfide ore hypergenesis zone of the Berezitovoe deposit in the Russian Far East was studied for the first time. It is shown that the mineral–organic associations widely abundant in the valley of Konstantinovskii Creek and represented by bright brown crusts on the surface of deluvial deposits were formed at the expense of the influence of acid highly mineralized mine waters from the Berezitovoe deposit. The mineral–organic associations found in the Creek valley may be considered as a new indicator for evaluation of the geoecological state of modern technogenic landscapes.

Procedure for obtaining new hybrid sorbents based on carbon fibers and chitosan-carbon materials modified with molybdenum, which determines the affinity of the sorbents for arsenate ions, is described. The surface morphology was examined and a qualitative chemical analysis of the surface of the composite sorbents was made by the method of scanning electron microscopy–energy-dispersive analysis. Sorption isotherms were obtained for unmodified materials, carbon fibers and chitosan-carbon materials, and hybrid sorbents in twicedistilled and tap water at low As(V) concentrations.

Perspectives of use of activated carbon materials modified with transition metal oxides for purification of water from arsenic were considered. Sorption isotherms for two types of hybrid sorbents based on carbon fibers modified with manganese oxide as birnessite as well as on fiber and chitosan-carbon materials on its basic modified with molybdenum determining affinity of the sorbents to arsenate-ions are presented.

Manganese oxides have been prepared on the surface of carbon fiber by simple methods: coprecipitation of manganese salts of different valence in the presence of fiber as a support or electrodeposition from Mn(II) salt solution on a carbon fiber cathode, in the presence of chitosan including, under oxidation with air oxygen conditions. The obtained samples have been characterized by scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Sorption properties of the composites toward As(V) have been studied. The relationships between sorption properties, structure, Mn valence, and manganese oxide surface morphology have been discussed.

Экспериментально изучено влияние серы на сорбцию платины углеродистым веществом (УВ) при 200–400°C и Робщ = 1 кбар. По результатам ИК-спектроскопии продуктов опытов зафиксировано ускоряющее влияние серы на конденсацию и ароматизацию УВ, при этом эффект серы на содержание Pt в органических фракциях заключен в пределах неопределенности анализа. На электронном сканирующем микроскопе (СЭМ) наблюдается образование многослойной пористой углеродной пленки на стенках ампул и платиновых подложках, непосредственно контактирующих с УВ. Состав пленки в зависимости от ее толщины (3–25 мкм) варьирует в пределах (мас. %): С = 61.06–100, Pt = 0–33.7, O = 0–5.17, S = 0–0.74. Пленка содержит включения микрокристаллов Pt, морфология которых меняется с увеличением длительности опытов от нано-микро-сфероидальной до субизометричной, таблитчатой и проволоковидной. В зависимости от размеров состав кристаллов варьирует (мас. %): Pt – 23.30–52.45, C – 49.57–73.52, O – 0–4.20. В керогене по данным СЭМ также обнаружены микрокристаллические выделения углеродистой платины, аналогичные по морфологии и составу присутствующим на пленке. Углеродистость микрокристаллов осажденной из раствора платины может быть следствием как фонового влияния субстрата пленки и керогена, так и кристаллизации их из платиноорганических комплексов. В кинетических опытах вследствие локальных электрохимических реакций образуются скопления наносфероидов (60–250 нм) вокруг более крупных микросфероидов (до 10 мкм), агрегация которых ведет к укрупнению и дальнейшей трансформации кристаллов. Сделан вывод о том, что полиморфизм, иерархическая агрегация и переменность составов платиновых образований характерны для углеродсодержащих систем вследствие их кристаллизации из платиноорганических метастабильных комплексов.

First data are reported on a new manifestation of carbonate-barite mineralization found at a site of methane emanations on the western slope of the Kuril Basin, Sea of Okhotsk. Morphological types of barite, aragonite, and low-magnesian calcite are considered in detail; the results of carbon and oxygen isotope study of carbonate concretions and crusts are presented. It is shown that the barite was formed in sediments owing to the diffusion infiltration of the barium-rich fluids through sedimentary succession. The component and isotope compositions of gases are determined and the relatively elevated content of heavy hydrocarbons is revealed. It was assumed that the relatively heavy isotope composition of carbonates is caused by the influence of fluid released from deep sedimentary horizons owing to the dehydration of clay minerals during post- sedimentation transformations. Obtained data show that the origin of carbonate-barite mineralization is related to the migration of hydrocarbons (mainly methane) and barium-bearing cold gas-fluid flows, which were derived not only from near-surface reservoirs but also from deeper-seated sources.

The effect of sulfur on platinum adsorption on carbonaceous matter (CM) was experimentally studied at 200–400°C and P tot = 1 kbar. The IR spectra of the experimental products indicate that sulfur accelerates HC condensation and aromatization, but the effect of sulfur on platinum concentrations in the organic fractions is within the analytical uncertainties. SEM images show the development of a multilayer porous carbonaceous film on the walls of the ampoules and platinum in physical contact with carbonaceous matter. The composition of the film varies, depending on its thickness (3–25 μm), within the following limits: 61.06–100 wt % C, 0–33.7 wt % Pt, 0–5.17 wt % O, and 0–0.74 wt % S. The film contains tiny Pt crystals, whose morphology varies with increasing duration of the experiments from nanometer- and micrometer-sized spheroids to subequant, tabular, and wire-like. Depending on their size, the composition of the crystals varies as follows: 23.30–52.45 wt % Pt, 49.57–73.52 wt % C, and 0–4.20 wt % O. According to our SEM data, the kerogen also contains tiny crystalline segregations of carbon aceous platinum whose morphology and composition are analogous to those on the film. The presence of carbon in the tiny platinum crystals deposited from solution can be explained by the background effect of the kerogen of the film and/or by their crystallization from organo-platinum complexes. In our kinetic experiments, local electrochemical reactions produced aggregates of nanometer-sized (60–250 nm) spheroids around larger micrometer-sized (up to 10 μm) spheroids, whose aggregation resulted in larger crystals and their further transformation. The polymorphism, hierarchical aggregation, and compositional variability of the platinum segregations are likely typical of car- bon-bearing systems because of their crystallization from metastable organo-platinum complexes.

Monzogabbrodiorites and monzodiorites from the Tatibin Group of Central Sikhote Alin (Primorye), which hosts the Glukhoe gold ore deposit, are considered with discussion of the most important data on the geological structure and composition of magmatic complexes and the results of U–Pb and SHRIMP dating. It is first established that mineral associations of the gold ore deposit include native Pt, Cu, and other compounds and mineral associations. Their formation conditions of both scientific and practical significance are analyzed.