Chemical synthesis of D-metal molybdates in aqueous solutions

Title : Chemical synthesis of D-metal molybdates in aqueous solutions

Abstract:

The possibility of chemically synthesizing d-metal molybdates in aqueous solutions free of hydrolysis products is demonstrated. A process flow diagram for obtaining the pure product is presented, comprising the following steps. An alkali metal molybdate and a soluble d-metal salt are dissolved in water, in which an appropriate medium is created beforehand. To dissolve the d-metal salt, the water is acidified to pH 5-6, and to dissolve the alkali metal molybdate, the water is alkalized to pH 8-9.

The prepared salt solutions are added simultaneously and at equal volumetric rates to a reaction vessel containing water with vigorous stirring, ensuring that the initial solutions are mixed only in the vessel containing distilled water. The aim of this work is to develop an optimal method for synthesizing chemically pure copper(II), cobalt(II), nickel(II), and lanthanum molybdates in aqueous solutions free of hydrolysis products.

Heavy metal molybdates possess a number of valuable properties, allowing them to be used in various fields of science and technology. Many of them have found widespread application as scintillation materials [1-5] due to their high density, radiation resistance, and ability to emit light upon absorption of ionizing radiation.

For example, lead molybdate and tungstate are used in detectors at the Large Hadron Collider at CERN as highly efficient scintillators [3] due to their high density of 8.28 g/cm³ and high radiation resistance. Molybdates are also in demand as photoconductors [1, 2], phosphors [2, 3], photocatalysts in polymer synthesis [3-5], and a pigment for coloring glazes in the production of high-strength ceramics [4].

Cobalt(II) molybdate is used in chemical processes as a catalyst and a pigment in the production of paints and inks, imparting a characteristic blue-green color [5]. Lanthanum molybdate can serve as a starting material for the production of various compounds and materials used in advanced technologies, such as electronics or catalysts [5]. Nickel molybdate is used in the production of complex catalysts, semiconductors, heat-resistant composite materials, electrolytes for nickel plating, batteries and heating elements, as well as in the production of stainless steel [5]. 

Biography:

Doctor of Chemical Sciences, Professor at Kabardino-Balkarian State University, Academician of the Russian Academy of Natural Sciences, Honored Scientist of the Kabardino-Balkarian Republic, and Honored Scientist and Educator of the Russian Academy of Natural Sciences.

Zhamal Akhmatovich Kochkarov's primary research interests include inorganic chemistry and the inorganic synthesis of molybdenum and tungsten compounds. Throughout his many years of research and teaching, 380 scientific articles have been published, including more than 200 scientific articles published in leading scientific journals indexed by the Higher Attestation Commission (HAC), Scopus, and Web of Science. He has received 20 patents and copyright certificates for inventions related to the development of: 1) heat accumulators used in alternative energy sources; 2) tungsten oxide bronzes used as stable dyes and catalysts; 3) molybdenum and tungsten carbides used as anti-corrosion refractory coatings on structural materials; 4) lead tungstate used as a radiation detector at the Large Hadron Collider. A monograph on this research area has been published, outlining the main scientific results. 30 textbooks for undergraduate and secondary school students have been published. Head of the postgraduate program in the field of "Inorganic Chemistry." Member of the editorial board of the journal "Izvestiya of the Dagestan State Pedagogical University. Natural and Exact Sciences.