Tanya Tsoncheva

Bio: Tanya Tsoncheva is an academic researcher from Bulgarian Academy of Sciences. The author has contributed to research in topics: Catalysis & Mesoporous material. The author has an hindex of 27, co-authored 116 publications receiving 2365 citations. Previous affiliations of Tanya Tsoncheva include Hungarian Academy of Sciences.

Cobalt oxide species supported on SBA-15, KIT-5 and KIT-6 mesoporous silicas for ethyl acetate total oxidation

Abstract: Cobalt oxide modified SBA-15, KIT-5 and KIT-6 mesoporous silicas with different pore size/pore entrances have been synthesized by a conventional wet impregnation method using cobalt nitrate as the precursor. The modified materials were characterized by N2-physisorption, XRD, TEM-EDX, XPS, FT-IR, UV–vis and TPR-TG with hydrogen. Their catalytic activities in total oxidation of ethyl acetate were evaluated. A good correlation was observed between the catalytic activity, and the presence of spinel-type Co3O4 in the materials. Supports with larger mesopores facilitated the formation of such easily reducible spinel particles. However, the interconnectivity of the mesopores and the uniformity of the channel dimensions also had an influence on the catalytic activity, implying that mass-transfer effects, especially in the case of supports with cage-like mesopores.

Mechanochemically synthesized nano-dimensional iron–cobalt spinel oxides as catalysts for methanol decomposition

Abstract: Iron–cobalt spinel oxide nanoparticles with different Fe/Co ratios have been prepared by the combination of chemical precipitation with simultaneous ultrasonic treatment and subsequent mechanical milling. For comparison, their analogues obtained by thermal synthesis were also studied. Phase composition and structural properties of iron–cobalt oxides are investigated by X-ray diffraction and Moessbauer spectroscopy. Their catalytic behavior in methanol decomposition to CO and methane is tested. A well-defined effect of the preparation method and Fe/Co ratio on the reduction and catalytic properties of iron–cobalt samples is established.

Nanosized iron and iron–cobalt spinel oxides as catalysts for methanol decomposition

Abstract: Nanosized iron and mixed iron–cobalt oxides supported on activated carbon materials and their bulk analogues prepared by thermal synthesis are studied by X-rays diffraction, Mossbauer spectroscopy, magnetic measurements and temperature programmed reduction. Their catalytic behavior in methanol decomposition to H 2 , CO and methane is tested. Phase transformations in the metal oxides affected by the reaction medium are also investigated. Changes in the reaction mechanism of the methanol decomposition after the metal oxides deposition on the support as compared to the bulk phases are discussed.

Cu and Cu-Based Nanoparticles: Synthesis and Applications in Catalysis.

Abstract: The applications of copper (Cu) and Cu-based nanoparticles, which are based on the earth-abundant and inexpensive copper metal, have generated a great deal of interest in recent years, especially in the field of catalysis. The possible modification of the chemical and physical properties of these nanoparticles using different synthetic strategies and conditions and/or via postsynthetic chemical treatments has been largely responsible for the rapid growth of interest in these nanomaterials and their applications in catalysis. In addition, the design and development of novel support and/or multimetallic systems (e.g., alloys, etc.) has also made significant contributions to the field. In this comprehensive review, we report different synthetic approaches to Cu and Cu-based nanoparticles (metallic copper, copper oxides, and hybrid copper nanostructures) and copper nanoparticles immobilized into or supported on various support materials (SiO2, magnetic support materials, etc.), along with their applications i...

Recent Advances in the Catalytic Oxidation of Volatile Organic Compounds: A Review Based on Pollutant Sorts and Sources.

Abstract: It is well known that urbanization and industrialization have resulted in the rapidly increasing emissions of volatile organic compounds (VOCs), which are a major contributor to the formation of secondary pollutants (e.g., tropospheric ozone, PAN (peroxyacetyl nitrate), and secondary organic aerosols) and photochemical smog. The emission of these pollutants has led to a large decline in air quality in numerous regions around the world, which has ultimately led to concerns regarding their impact on human health and general well-being. Catalytic oxidation is regarded as one of the most promising strategies for VOC removal from industrial waste streams. This Review systematically documents the progresses and developments made in the understanding and design of heterogeneous catalysts for VOC oxidation over the past two decades. It addresses in detail how catalytic performance is often drastically affected by the pollutant sources and reaction conditions. It also highlights the primary routes for catalyst deactivation and discusses protocols for their subsequent reactivation. Kinetic models and proposed oxidation mechanisms for representative VOCs are also provided. Typical catalytic reactors and oxidizers for industrial VOC destruction are further discussed. We believe that this Review will provide a great foundation and reference point for future design and development in this field.