Tallinn University of Technology

About the Laboratory of Inorganic Materials

Laboratory of Inorganic Materials has developed from the Laboratory of Mineral Fertilizers established by academician Mihkel Veiderma in 1965 and leaded by Dr. Rein Kuusik. Later, due to expansion and changes in the research area, it existed as the Laboratory of Inorganic Technology and starting from January 2017, related to bigger structural changes in TalTech, the research group belongs to the Department of Materials and Environmental Technology as the Laboratory of Inorganic Materials.

Research activities of the laboratory have been focused on the part of inorganic materials in the broad area of materials science. Its research covers chemistry and technology of inorganic materials, more specifically, fundamental and applied research of inorganic multicomponent systems in order to work out new innovative materials, to find application and new utilization methods for Estonian mineral resources, to diminish emissions of industrial wastes and to find possibilities for their reuse and/or environment-friendly storage.

Research in the laboratory at current period is mainly focused on waste management in oil shale industry – to reuse oil shale ash, diminish GHG emissions and to clarify chemical-technological fundamentals of the related processes. Research directions are related to mineral carbonation, PCC and curing materials, chemistry of apatites, enrichment and treatment technologies of Estonian phosphorite, oil shale oxy-combustion and other thermal processes, with the aim to reach to feasible, environmentally sound, optimized applications, using experimental research together with mathematical modeling.

The research in the lab up to 2002 has been analyzed more in detail by the long-term scientific supervisor of the research group, academician Mihkel Veiderma (1929-2018).

Prof. Andres Trikkel
Head of the lab

Koosseis 2018

Staff and Apparatus

Members of the research group (linked to ERIS - Estonian Research Information System):

Detailed list in  TalTech web (room numbers, phone numbers, etc)

Scientific apparatus involves:

  • TG-DTA + MS analysis unit (thermal analyzer Setaram Labsys Evo coupled to MS spectrometer Pfeiffer);
  • TG-DTA thermal analyzer Setaram Setsys Evo;
  • TG-DTA thermal analyzer Linseis STA-PT 1600 for pressurized experiments up to 5 bar;
  • Dilatometer (Setaram);
  • AAS spectrometer Varian SpectrAA 50/55;
  • UV-VIS spectrometer Biochrome Libra;
  • Sorptometer KELVIN 1042 for BET surface analysis by N2 adsorption method;
  • High-pressure Hg-porosimeter Poremaster 60-17 for porosity distribution analysis;
  • Laser analyzer Horiba LA-950V2 for size distribution measurements;
  • Carbon analyzer ELTRA CS-580 (TC ja TIC);
  • Reactor unit for solution chemistry in the environment of different gases Lara Controlled Laboratory Reactor (Radleys);
  • Automatic titrator Mettler Toledo T90;
  • Extruder Bonnot 2 1/4" for granulation;
  • Device for measuring granula strength CT3 25K (Brookfield Engineering);
  • Gas analyzer Testo 350-S/-XL Flue Gas Analyzer (CO2, SO2, H2S, O2)


There are two main research directions in the laboratory:

Research in natural inorganic materials and industrial wastes

(Mai Uibu, Rein Kuusik, Tiit Kaljuvee, Can Rüstü Yörük et al.)

  • Heterogeneous processes in the multicomponent systems CaCO3 – CaO – SO2 – CO2 – O2 – CaSO4 or in its subsystems being essential in environmental technology;
  • Chemistry and transformations of sulphur or carbon containing inorganic compounds at thermal treatment of fossil and waste fuels (Estonian oil shale, its semi-coke, coal etc.);
  • Accelerated carbonation processes;
  • Modeling and simulation of calcination – carbonation – sulphation processes of lime-containing materials;
  • PCC from the wastes of oil shale based power production;
  • Fundamentals of oxy-fuel combustion of oil shale;
  • Granulation technologies for oil shale ash and improvement of safety of nitrogen fertilizers;
  • Oil shale ash as additive in ceramics, clay bricks and construction materials;
  • Implementation of high temperature fluidized bed technique.

Research in phosphatic materials

(Kaia Tõnsuaadu, Kadriann Tamm, Marve Einard et al.)

  • ~50 years of experience in natural apatites - composition, structure, chemistry and processing technologies;
  • Synthesis of cation and anion substituted apatites by precipitation and sol-gel methods;
  • Complex characterisation of composition and structure of substituted apatites as well as their utilisation in organic catalysis;
  • Chemistry and mechanism of heavy metal binding from solutions by different substituted apatites;
  • Oil shale ash as sorbent for phosphorus recycling;
  • Enrichment and treatment possibilities of Estonian phosphorite;
  • New processing technologies of Estonian phosphorite and accompanying minerals.

Publications of the research group

Most important projects

Since 2017 after structural changes in TalTech, the projects of the laboratory are not anymore registered separately by ERIS, as the lab belongs now to the Dept. of Materials and Environmental Technology. Short abstracts of the newer projects are presented here below, descriptions of the older projects are linked to ERIS web.

ResTA23: Quality and properties of Estonian shelly phosphorite as a potential source for phosphorus and rare earth elements and its complex processing technologies (2020-2023, ETAG, A.Trikkel)

Both rare earths and phosphorus are on the list of European critical raw materials, necessitating the discovery, exploitation and research of new resources. Estonian shelly phosphorites are the largest known phosphorite resource in Europe, containing also rare earth elements in elevated concentrations. From the perspective of phosphorite valorisation, it is critical to develop new technologies for the production of phosphoric acid and phosphorous fertilizers in order to find suitable, innovative and environmentally friendly solutions for high-quality end products. The aim of the study, based on integrated geological and mineralogical methods, modeling of geometallurgical characteristics of this resource and technological experiments, is to clarify the classification possibilities of shelly phosphorites, depending on their phosphorus and rare earths content, to interpret the distribution of such raw materials, and to analyze their potential processing technologies (Project in ERIS web)

IUT3319: Fundamentals of multicomponent mineral-organic systems: Chemistry, modeling and sustainable processing (2015-2020, ETAG, A.Trikkel)

The project is focused on waste management in oil shale industry – to reuse oil shale ash and diminish GHG emissions through a complex of ideas and closely related methods in solution and thermochemistry combined with modeling. The primary aim is to clarify chemical-technological fundamentals of the processes in the multicomponent heterogeneous mineral-organic aqueous or gas – solid systems related to PCC production, oil shale or semicoke oxy-combustion and recycling of phosphorus together with extended chemistry of cation-substituted apatites for chemical synthesis, enabling to reach feasible, environmentally sound, optimized applications and generalize the novel know-how. (Project in ERIS web) (Summary of the Main Results)

RITA 1: Climate change mitigation with CCS and CCU technologies [ClimMIT] (2019-2021, ETAG, M.Uibu, A.Trikkel)

Estonia has one of the highest per capita greenhouse gas (GHG) emission rates and carbon-intensity levels in the EU. To decrease GHG emissions sharply best options for implementing carbon capture and utilization (CCU) technologies must be identified. The main goal of the project is to assess the suitability of various CCU technologies and develop scenarios for adopting these in the Estonian oil shale industry. Also, environmental effects of the most promising solutions are studied along with the technological and economic capacities for utilizing captured CO2 in other industries. Economic analysis focuses on differences in per unit costs of alternative capturing technologies, their sensitivity to CO2 quota and electricity prices and investment subsidising needs as well as export markets for Estonian captured CO2. The project results in a multifaceted overview of the feasibility of investing in carbon capture infrastructure to help to minimize GHG from the oil shale industry in Estonia. (Project web-page)

FLAME: Fly Ash to Valuable Minerals (2017-2020, EIT-KIC, A.Trikkel, C.R.Yörük)

The FLAME project develops the dusty plasma separation (DPS) technology to enable dry (ultra)fine mineral classification and extraction of valuable minerals from both primary and secondary resources in order to minimize losses of unused materials. The provision of large amounts of high-quality (ultra)fine minerals to the market is expected to engender the development of more durable and sustainable materials and products in related markets such as high-value construction materials and composite materials. The first DPS technology users are coal/oil shale power stations which produce fly ash, and have to dispose it or find markets for it. The project targets the development of at least three added value products. The main product is the DPS equipment, but also the value of the DPS output products – the ultrafine and very fine fractions of fly ash. To the end of the FLAME project the system prototype will be demonstrated in an operational environment (level TRL 7). (Project web-page)

CLEANKER: Clean Clinker Production by Calcium Looping Process (2017-2021, Horizon 2020, M.Uibu)

The cement industry is a key-sector for the reduction of CO2 emissions. Cement production is responsible for about 27% of global anthropogenic CO2 emissions from industrial sources worldwide. The focus of CLEANKER is demonstrating the feasibility of the integrated Ca-Looping process at industrial scale in a new demo system treating 4,000 m3/h of flue gas emitted by the Buzzi Unicem cement plant in Vernasca (Piacenza, Italy). Project is coordinated by L.E.A.P. (Laboratory for Energy and Environment) from Italy. Project consortium is composed from 13 partners from 7 countries including two departments from Tallinn University of Technology (Department of Geology and Department of Materials and Environmental Technology: Laboratory of Inorganic Materials). TTÜ is a coordinator of the Work Package 7 (Transport, utilization and storage study) including 7 tasks and 7 deliverables. Among these tasks are: Techno-economic modelling of selected local and regional CCUS scenarios for Vernasca, Kunda and Slantsy cement plants (TTÜ-GI); Lab-scale experiments on waste oils shale ash and CDW carbonation and recommendations for the design of the mineralization reactor in Vernasca (TTÜ-MK); Producing of concrete using waste materials from cement plants and Ca-Looped CO2 trapped in the Vernasca demo system will be finaly demostrated in the project. (Project web-page)

RITA 1: Efficient, environmentally friendly and sustainable use of Earth Resources (2017-2020, ETAG, K.Tõnsuaadu, M.Uibu, A.Trikkel)

Aim of this interdisciplinary project is to provide information on the best available and new innovative technologies for utilization of existing mineral resources and information on properties and possible processing technologies for potential resources in Estonia. Subtask RITA1/01-01-07 elaborates the properties of oil shale (OS) processing solid waste materials formed in new boilers and retorts put into use in last years. It focuses on reusability and environmental impact of these materials and provides the basis for choosing the most effective, profitable and environmentally less harmful reuse technologies for Estonian OS wastes. Subtask RITA1/01-01-11 studies the possibilities of application of novel methods for enrichment of Estonian shelly phosphorite ore and processing its concentrates into final products, and the distribution and removal of potentially harmful and/or useful accompanying components. (About the project)

Lep19098: Põlevkivituha väärindamise ja ringlusse suunamise võimaluste rakendusuuring / Applied research of the possibilities of oil shale ash valorisation and recycling (2019−2021, R-OSA Service OÜ, M.Uibu).
(About the project)

Earlier projects:

  • Uuring tööstusjäätmetest ehituslike täitematerjalide saamiseks koos CO2 sidumisega / Production of construction materials from industrial wastes and CO2 (2016-2018, KIK, M.Uibu).
  • Earlier projects and contracts (Link to ERIS web)

For students

Laboratory of Inorganic Materials offers possibilities to carry out practical BSc, MSc and PhD studies on different processes related to environmental protection (utilization of wastes, diminishing GHG emissions) as well as many other topics in inorganic technology.

Many topics are related to energetics, in Estonian context, to environmental concerns of oil shale based power production -  abatement of CO2 emissions, oil shale ashes and their new utilization methods, oil shale oxy-combustion, processes of mineral carbonation. Another direction is related to natural and synthetic apatites (apatites as catalysts, apatites for binding heavy metals from waste-water). In addition, new, more environmentally friendly technologies for processing Estonian phosphorite and accompanying minerals have appeared on the agenda.

The list of recent PhD theses topics completed in the Laboratory of Inorganic Materials is presented below.

  • Hakan Berber. Accelerated Carbonation Treatment of Industrial Wastes: Physicochemical, Environmental and Economic Aspects / Hinnang Iru elektrijaamas olmejäätmete põletamisel tekkiva lendtuha kasutusvõimalustele (supervisors V. Voronova, M.Uibu, defended in 2020)
  • Can Rüstü Yörük. Experimental and Modeling Studies of Oil Shale Oxy-fuel Combustion / Põlevkivi hapnikus põletamise eksperimentaalne uurimine ja modelleerimine (supervisors A.Trikkel, R.Kuusik, defended in 2016)
  • Kadriann Tamm. Leaching of the Water-Soluble Calcium Components of Oil Shale Waste Ash / Kaltsiumiühendite leostumine põlevkivituha vesisüsteemides (supervisors M.Uibu, J.Kallas, R.Kuusik, defended in 2016)
  • Irina Klimova. Modification of Ammonium Nitrate Fertilizer / Ammooniumnitraatväetiste modifitseerimine (supervisors T.Kaljuvee, A.Trikkel, defended in 2014)
  • Aleksandr Käkinen. The role of physico-chemical properties and test environment on biological effects of copper and silver nanoparticles / Vase ja hõbeda nanoosakeste füüsikalis-keemiliste omaduste ja testikeskkonna mõju nende bioloogilisele toimele (supervisors A.Kahru, KBFI; R.Kuusik, defended in 2014)
  • Karin Viipsi. Impact of EDTA and humic substances on the removal of Cd and Zn from aqueous solutions by apatite / EDTA ja humiinaine mõju Cd ja Zn eraldamisele vesilahusest apatiidiga (supervisor K.Tõnsuaadu, defended in 2012)
  • Riina Salmimies, Lappeenranta University of Technology.  Acidic dissolution of iron oxides and regeneration of a ceramic filter medium (supervisor J.Kallas, defended in 2012)
  • Olga Velts. Oil Shale Ash as a Source of Calcium for Calcium Carbonate: Process Feasibility, Mechanism and Modeling / Põlevkivituhk kaltsiumkarbonaadi toormena: protsessi teostatavus, mehhanism ja modelleerimine (supervisors R.Kuusik, J.Kallas, defended in 2011)
  • Mai Uibu. Abatement of CO2 emissions in Estonian oil shale-based power production / CO2 emissiooni vähendamisvõimalused põlevkivienergeetikas (supervisors R.Kuusik, A.Trikkel, defended in 2008)
  • Merike Peld. Substituted Apatites as Sorbents for Heavy Metals /Asendustega apatiidid raskmetallide sidujatena (supervisor K.Tõnsuaadu, defended in 2005)
  • Andres Trikkel. Estonian Calcareous Rocks and Oil Shale Ash as Sorbents for SO2 / Eesti karbonaatsed kivimid ja põlevkivituhk vääveldioksiidi sorbendina (supervisors R.Kuusik, M.Veiderma, defended in 2001)
In the lab