[en] Synthetic analogues of naturally occurring mineral murataite [8]A6[6]V12[5]S4[4]TH40, h (A = Y, Na; V = Ti; C = Fe; T = Zn; X = O, F, value of h depends on a cationic composition) are under consideration as candidate matrixes for immobilizing radioactive waste of different chemical composition (Laverov et al., 2011). Synthetic murataite has structural varieties (polytypes) with triple, fivefold, sevenfold and eightfold (M3, M5, M7, M8) recurrence of lattice spacing as to fluorite cell (Laverov et al., 2011). A maximum content of murataite phases (a volume fraction up to 95%) is attained in the ceramics with the following composition, wt.%: TiO₂ 55-60%, MnO 8-10%, CaO 8-10%, Al₂O₃ 4-5%, Fe₂O₃ 4-5%, ZrO₂ 5-8% (precursor) with high level waste (HLW) (oxides of actinides – Th, U, Np, Pu and rare-earth elements as well as their mixtures) 8-10%.In order to investigate radiation stability of murataite, ceramics samples of the calculated composition (% wt) Al₂O₃ 3.8; CaO 10.5; TiO₂ 54.0; MnO 10.6; Fe₂O₃ 6.0; ZrO₂ 4.6; ThO₂ 8.1; Cm₂O₃ 2.4 (including 1.8% of ²⁴⁴Cm) and specific activity 5.5x10¹⁰ Bq/g were fabricated with the use of cold compacting, sintering or melting followed by crystallization. They were exposed for 600 days (Laverov et al., 2011) to accumulate dose of radiation with regular examination of their structural properties. Polytypes of pyrochlore -murataite series with fivefold (M5), eightfold (M8) and triple (M3) fluorite cell as well as impurity phases (crichtonite, iron –manganese titanates etc.) were found out in the samples. Polytype M5 that is the major concentrator of curium becomes X-ray amorphous at 2.73x10¹⁸ alpha-decay/g or 0.21 dpa (displacement per atom). The M3 polytype lattice as well as the crichtonite lattice undergoes a low disordering at this dose value because of less amount of curium. A 5h annealing at 1250℃ causes recovery of phase composition in ceramics. Another possible application of murataite-based ceramics is incorporation of the waste from pyrochemical SNF reprocessing. To investigate interphase separation of elements in oxide deposit that is a concentrator of fission products after pyrochemical processing of spent nuclear fuel, a sample containing the elements that imitate high-level radioactive waste (HLRW) was used. It had the following composition: 3.9 SrO, 21.9 MoO₃, 27.3 CeO₂, 25.5 Pr6O₁₁, 5.0 Nd₂O₃, 7.8 Sm₂O₃, 5.3 Eu₂O₃, 3.3 UO₂. The charge (its composition is given above) was mixed in a weight ratio of 10:1 with simulated HLRW and melted at 1350℃ (Lizin et al., 2017). X-ray diffraction analysis and scanning electron microscopy made it possible to reveal that murataite makes up at least 60 vol.% of the aforesaid sample. The remaining constituents are zirconolite, crichtonite and perovskite. Murataite incorporates mostly rare-earth elements and actinides (uranium) among the elements imitating radioactive waste. Some rare-earth elements are confined in zirconolite and perovskite (mainly Ce and Nd are confined in the last one). As molybdate phases (Ca,Ba,Sr)MoO₄ that are soluble in water are present in small amounts, they cause removal of strontium and cesium from the matrix. This paper discusses the possibility of including dense calcium into murataite from acid (nitric acid, ethane, ethylene-diamino-tetra-acetic acids with a weight ratio of 5; 0.5; and 0.5%, respectively) and alkaline decontamination solutions (KMnO₄ and NaOH with a weight ratio of 0.5 and 5%, respectively). The aforesaid solutions are used for decontamination of hot cell equipment intended for radiochemical production. Solutions were mixed in equal volumetric ratios and evaporated to dryness. The initial charge of the following composition, wt.% TiO₂ 55%, MnO 8.94%, CaO 10%, Al₂O₃ 5%, Fe₂O₃ 5%, ZrO₂ 5%, waste 11.06% was prepared. It was melted at 1350℃. The resultant sample is composed of murataite, polytype 3M (lattice parameter a = 14.63±0.01 Å) and perovskite. Such a process of decontamination waste management will allow for enhancing efficiency and safety of waste management.