The paper focuses on a transition from studying synthetic analogs of rare titanosilicate minerals (lintisite, ivanyukite, and zorite) in the powdery state to investigating their new granulated forms. Five different methods for granulating titanosilicate samples are tested: fluidized bed and spray dry granulation, spray bed granulation, screw rotor granulation, and manual pressing of paste through a stainless-steel sieve with a 1 mm mesh size. The results of studying sorption of trace amounts of 137Cs and 90Sr radionuclides from model solutions of various compositions onto inorganic sorbents in powdered and granulated forms are presented.

Materials of the 2D zeolite class retain local catalytically active sites and the stability of traditional zeolites but with layered structures. Synthetic and naturally occurring single- and multilayer apophyllite-related compounds are prototypes of advanced industrial materials for use in various technologies. Their surface chemistry allows for functionalization, and these layers serve as fundamental building blocks for zeolitic frameworks. The discovery of the first triple-layer silicate, günterblassite, provided a critical link that established a fundamental crystal–chemical relationship between layered and framework structures in a wide range of micro- and mesoporous minerals and synthetic materials. The most prominent topic in the development of 2D zeolites remains the synthesis and structural characterization of these 2D zeolite structures This review offers a comprehensive overview of the current state of 2D and 3D zeolites constructed based on apophyllite-type layers. In accordance with the terms of modular crystal chemistry, we present a straightforward classification scheme based on the topological and symmetrical distinctions of the layers and provide ways for their stacking, creating a valuable basis for understanding the modular assembly of advanced porous materials.

An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

A simple method for the direct transformation of Sr-exchanged titanosilicate with the sitinakite structure (IONSIV) into ceramic material through cold pressing and subsequent sintering at 1100 °C for 4 h is presented. The temperature transformation of Sr-exchanged sitinakite showed the stages of recrystallization of the material with the formation of Sr-Ti phases matsubaraite (Sr4Ti5[Si2O7]2O8), jeppeite (SrTi6O13), tausonite (SrTiO3), and rutile. Leaching experiments showed the efficiency of fixation of Sr cations in a ceramic matrix; extraction into water does not exceed 0.01% and desorption in 1 M HNO3 solution is only 0.19% within three days. The leaching rates of immobilized Sr demonstrate the structural integrity of the formed phases in the ceramic (2.8 × 10−5–1.0 × 10−5 g/(m2·day). The decrease in the crystallinity of the initial Na-sitinakite, which is achieved by reducing the synthesis temperature from 250 to 210 °C, does not affect the sorption capacity and the fixation of cations in the ceramic matrix. The obtained results confirm the prospect of using inexpensive precursors, titanium ore enrichment waste, for the synthesis of sorption materials.

An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Flexible crystal() structures, which exhibit() single-crystal()-to-single-crystal() (SCSC) transformations(), are attracting attention() in many applied aspects: magnetic() switches, catalysis, ferroelectrics and sorption. Acid treatment() for titanosilicate material() AM-4 and natural() compounds with the same structures led to SCSC transformation() by loss() Na+, Li+ and Zn2+ cations with large structural() changes (20% of the unit()-cell() volume()). The conservation() of crystallinity through complex() transformation() is possible due() to the formation() of a strong hydrogen bonding() system(). The mechanism() of transformation() has been characterized using single-crystal() X-ray() diffraction analysis(), powder() diffraction, Rietvield refinement, Raman spectroscopy and electron microscopy. The low migration() energy() of cations in the considered materials() is confirmed using bond()-valence and density() functional() theory() calculations, and the ion conductivity of the AM-4 family's materials() has been experimentally verified.

Titanosilicates comprise a broad class of materials with promising technological applications. The typical obstacle that restricts their industrial applicability is the high manufacturing cost due to the use of specific organotitanium precursors. We herein report a new approach to the synthesis of titanosilicates using an inexpensive inorganic precursor, ammonium titanyl sulfate (ATS or STA), (NH4)2TiO(SO4)2∙H2O. The latter is an intermediate in the processing of titanium-bearing concentrates produced from apatite-nepheline ores. In this paper, the new synthetic approach is exemplified by the microwave-assisted synthesis of IONSIVE-911, one of the most effective Cs-ion scavengers. The method can be modified to synthesize various titanosilicate compounds.

In this study, the one-pot synthesis of glycidol from glycerol (Gly) and dimethyl carbonate (DMC) was demon-strated in the presence of novel composite materials based on the microporous layered titanosilicate AM-4 (Aveiro-Manchester material number 4) and a zeolitic imidazolate framework ZIF-8. It was found that the re-action rate and selectivity towards glycidol depended on the ZIF-8 content in composite. Maximum 74.4% yield of glycidol with 92.5% conversion of glycerol was observed in the presence of 0.5%ZIF-8/AM-4 at DMC/Gly-molar ratio of 2, catalyst/glycerol weight ratio of 7.9 wt.% and temperature of 100 degrees C for 8 h. The catalytic properties of developed ZIF-8/AM-4 composite correlated with (1) ZIF-8 particle size, (2) the decreasing basic sites strength, and (3) the increasing microporosity of materials.

A number of minerals that have become prototypes of functional materials have been discovered on the Kola Peninsula.The paper presents structural adaptation mechanisms accompanying ion exchange reactions in zorite, sitinakite, and ivanyukite.

Nanoparticles in titanite CaTiSiO5 were found using transmission electron microscopy. Chemical and XPS analyzes of the nanoparticles were performed. The study showed the content of the elements Si, Ti and Ca to be about 19, 14 and 12 % in the ore, respectively, belonging to the titanite phase. Based on TEM images, it was established that titanite exhibits a disordered lamellar structure with a diameter of 3 to 5 nm and an interplanar distance of about 6.3 A.

Nepheline, ideally Na3K(Al4Si4O16) is a key mineral of silica-undersaturated igneous rocks. Under subsolidus conditions, nepheline is intensively replaced by numerous secondary minerals, of which various zeolites (mainly natrolite, analcime, gonnardite), as well as cancrinite, muscovite and Al-O-H phases (gibbsite, böhmite, nordstrandite) are the most common. In the rocks of the Lovozero alkaline massif (Kola Peninsula, NW Russia), nepheline is extensively replaced by the association natrolite + nordstrandite ± böhmite ± paranatrolite. To reproduce the conditions for the formation of such a mineral association, a series of experiments were carried out on the dissolution of nepheline in deionized water, 0.5 mol/L NaCl, 0.5 mol/L NaOH, and 0.1 mol/L HCl at 230 °C for 1/5/15 days. When nepheline is partially dissolved, phases and mixtures of phases precipitate on the surface of its grains, and these phases were diagnosed using X-ray powder diffraction and Raman spectroscopy. Observations in natural samples and experimental studies have shown that the nepheline alteration in the rocks of the Lovozero massif with the formation of natrolite and Al-O-H phases occurred under the influence of a high to medium salinity solution at a pH of near 6.

Eudialyte-group minerals (EGMs) are typical accessory or rock-forming minerals of the Lovozero peralkaline massif (Kola Peninsula, Russia). The EGM grains in the rocks of the massif are often replaced by an association of various secondary minerals such as lovozerite and wöhlerite group minerals, as well as terskite, catapleiite, elpidite, gaidonnayite, vlasovite, zircon, and loparite-(Ce). However, EGMs in the Lovozero massif can be not only pseudomorphized, but also partially or completely dissolved. The partial dissolution of eudialyte grains was simulated in three series of experiments, and the results obtained were compared with natural samples. Observations in natural samples and experimental studies have shown that the partial dissolution of eudialyte-group minerals occurs in two stages: (1) loss of sodium and hydration; (2) loss of other cations not included in the zirconosilicate framework. This process proceeds most intensively in acidic hydrothermal solutions and may be responsible for the appearance of new mineral species in the eudialyte group.

Аннотация.Исследованы ионообменные и сорбционные свойства мурманита в отношении катионов Pb 2+ и Cd 2+ .Мурманит способен полностью обменивать катионы Na + на Cd 2+ и Pb 2+ в хлоридных растворах при температуре 160 ° С. Внедрение свинца в межслоевое пространства мурманита происходит по схеме 2Na + ↔ Pb 2+ + □.Кадмий входит в кристаллическую структуру мурманита по изоморфной схеме 2Na + ↔ Cd 2+ + □, замещая натрий в октаэдрических позициях.Упорядочение занятых и вакантных октаэдрических позиций для Cd-pзамещённой формы приводит к изменению элементарной ячейки с исходной пр.гр.P ,a = 5.3822( 6), b = 7.0538(8), c = 11.6477(15),α = 86.385(9),β = 81.967(10),γ = 89.970(9)в диагональную α = 8.8154 (11), b = 8.8363(11), c = 11.694(4),α = 98.786(17), β = 90.954(17),γ = 106.039(11).

The microporous titanosilicate sitinakite, KNa2Ti4(SiO4)2O5(OH)·4H2O, was first discovered in the Khibiny alkaline massif. This material is also known as IONSIV IE-911 and is considered as one of the most effective sorbents for Cs+ and Sr2+ from water solutions. We investigate a mechanism of cooperative crystal chemical adaptation caused by the incorporation of La3+ ions into sitinakite structure by the combination of theoretical (geometrical–topological analysis, Voronoi migration map calculation, structural complexity calculation) and empirical methods (PXRD, SCXRD, Raman spectroscopy, scanning electron microscopy). The natural crystals of sitinakite (a = 7.8159(2), c = 12.0167(3) Å) were kept in a 1M solution of La(NO3)3 for 24 h. The ordering of La3+ cations in the channels of the ion-exchanged form La3+Ti4(SiO4)2O5(OH)·4H2O (a = 11.0339(10), b = 11.0598(8), c = 11.8430(7) Å), results in the symmetry breaking according to the group–subgroup relation P42/mcm → Cmmm.

The production of electrolytic nickel includes the stage of leaching of captured firing nickel matte dust. The solutions formed during this process contain considerable amounts of Pb, which is difficult to extraction due to its low concentration upon the high-salt background. The sorption of lead from model solutions with various compositions by synthetic and natural titanosilicate sorbents (synthetic ivanyukite-Na-T (SIV), ivanyukite-Na-T, and AM-4) have been investigated. The maximal sorption capacity of Pb is up to 400 mg/g and was demonstrated by synthetic ivanyukite In solutions with the high content of Cl− (20 g/L), extraction was observed only with a high amount of Na (150 g/L). Molecular mechanisms and kinetics of lead incorporation into ivanyukite were studied by the combination of single-crystal and powder X-ray diffraction, microprobe analysis, and Raman spectroscopy. Incorporation of lead into natural ivanyukite-Na-T with the R3m symmetry by the substitution 2Na+ + 2O2− ↔ Pb2+ + □ + 2OH− leds to its transformation into the cubic P−43m Pb-exchanged form with the empirical formulae Pb1.26[Ti4O2.52(OH)1.48(SiO4)3]·3.32(H2O).

In this contribution the sorption properties of the framework-layered silicate mineral armbrusterite to monovalent Cs+ and Rb+ cations were reported. The models of crystal structures for the Cs-modified mineral and its decationized form are also reported. The results of experiments on the selection of necessary conditions for the synthetic analogue armbrusterite synthesis are discussed.

The description of a new and insufficiently studied mineral armbrusterite is presented in this paper. The mineral was analyzed from the point of view of its chemical properties and prospects for practical application. The mineral's sorption properties for arsenic and cesium ions were studied. The possibility of synthesis an analog of the mineral due to hydrothermal synthesis was estimated