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The relevance of the research.The solution of environmental problems in the agricultural sector is possible throughthe use of new slow-released or controlled release fertilizers.This article presents options for using montmorillonite as a component of modern nitrogen fertilizers with controlled properties and the results of studying mineral transformations in the mechanochemical activation at various parameters. The main aim of the work was to evaluate activation mechanisms of the montmorillonite as an inhibitor of nitrogen composites for creating slow-release fertilizers. The methods: mechanochemical activation by planetary and ring mills, X-ray diffraction, scanning electron microscopy, infrared spectroscopy, differential thermal analysis. Results.The proportion of intercalated urea in montmorillonite (for M1N1 mixtures) is slightly changed within 22,3...23,2% for the planetary mill activation for 3, 8 or 11 minutes. The maximum intercalation degree of 23,2% was achieved in the activation for 3 minutes. However, about 40...50% of the aggregated particles are covered with an outer shell of excess urea up to 2,5 µm in the thick after an 11-minute operation for the planetary mill. The proportion of intercalated urea in montmorillonite is slightly changed from 23,2 to 21,6% for the activation time increases from 30 to 120 minutes in a ring mill. While the activation time was increased, urea microcrystallites were formed on the surface of mineral particles. Mineral products synthesized by planetary or ring mill activation have the potential to be used as slow-release fertilizers with several beneficial functions. Composites synthesized with 11-minute or 120-minute planetary or ring mills, respectively, are characterized by two types of nitrogen. Fertilizers will initially release nutrients at a high rate from the outer urea film. After that, exchangeable nitrogen will be released from the interlayer space of montmorillonite, thereby providing prolonged nutrition of the plants.

The global energy industry works towards an increased use of carbon-neutral biomass. Nutshell represents a regional bio-waste, i.e., a bio-energy resource. Pyrolysis is a common method for processing biomass into valuable energy products. The heat demand, however, limits pyrolysis applications. Yet, such demand may be addressed via exothermic pyrolysis reactions under selected operation conditions. Making the pyrolysis of Siberian pine nutshell autothermic comprised the objective of the study. The study involved analytical methods together with a pyrolysis experiment. The analytical methods included a thermogravimetric analysis combined with differential scanning calorimetry and an integrated gas analyzer. Thermophysical characterization was executed using a thermal diffusivity analyzer with the laser flash method. At 650 °C, pyrolytic heat was released in the amount of 1224.6 kJ/kg, exceeding the heat demand of 1179.5 kJ/kg. Pyrolysis at a lower temperature of 550 °C remained endothermic, although the combusted gas product provided 847.7 kJ/kg of heat, which, together with exothermic release, covered the required heat demand for the pyrolysis process.

This research presents the mechanical creation of smart fertilizers from a mixture of smectite and urea in a 3:2 ratio by using the planetary milling technique. The smectite–urea composites show intercalation between urea and mineral, which increases steadily with increasing activation time. A shift of X-Ray Diffraction basal reflections, intensities of Fourier transform infrared spectroscopy (FTIR) peaks, and weight losses in thermogravimetric analysis (TG) document the systematic crystallo-chemical changes of the composites related to nitrogen interaction with activation. Observations of the nanocomposites by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) corroborate the inference. Nitrogen intercalates with smectite in the interlayer space and remains absorbed either within micro-aggregates or on the surface of activated smectites. Soil leaching tests reveal a slower rate of nitrogen than that of traditional urea fertilizers. Different forms of nitrogen within the composites cause their differential release rates to the soil. The formulated nanocomposite fertilizer enhances the quality and quantity of oat yield.