Every year there is deterioration in water quality. This is due to human activity. The current environmental strategies of many countries motivate the scientific community to develop reliable, economically viable and environmentally friendly technologies that are able to remove pollutants from the environment, including water. The study purpose is to determine of influence regularity of the bio-adsorbent composition and amount, which consists of red and black tea leaves mixture, on the Cd, Co and Ni adsorption process based on experimental data. As well as determine the most rational bio-adsorbent dose and the necessary red and black tea dose in bio-adsorbent to achieve MPC of heavy metals, with which process duration will be minimal. Initially, to study the adsorption process kinetics, the nature of the curve that describes the obtained experimental values was visually analyzed. To determine the adsorption process kinetic regularity, which most adequately and reliably describes the experimental data and to determine the values of the coefficients in the exponential regularity, the least squares method was used. It was observed that for Cd and Co, an increase in the black and red tea amount leads to a drastic reduction of the adsorption process time (up to 10 times); while for Ni the black tea addition slows down the adsorption process. Ni adsorption is the most complex and for certain bio-adsorbent composition values, complete Ni removal cannot be achieved in a technologically reasonable adsorption time. The technological process of Cd, Co and Ni adsorption can be expedient, if it is carried out in several stages with optimal red and black tea amounts for each of the metals. Adsorption process kinetic regularity, which was determined, can be used to calculate of adsorption process technological parameters in values wide range.

The origins of changes in the catalytic activity of platinum catalysts in the ammonia oxidation process are studied. A general mathematical model for the dependence of the catalyst activity on the operation time of a single platinum gauze is proposed. Simpli®ed expressions for the catalytic activity of two basic types of catalyst sets are obtained. Optimization of the catalyst operation mode is investigated and an optimal mode is selected based on the industrial data.

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Purpose: To develop a new concept of laboratory support for learners at different levels of education to maintain a high education quality in conditions of limited opportunities, such as lockdown, lack of funding, etc. Design/methodology/approach: To create a new concept, the practical experience of school teachers, educators of technical colleges and universities, research workers, as well as experience of scientists in the educational field published in open information' sources was taken into account. The development of a new concept was carried out from 2014 to 2016, and its implementation, introduction into the educational process, and possible ways to solve technical and organizational difficulties from 2016 to the present. In the last year, special attention was paid to distance learning. Findings: The development and the first practical steps to implement the new concept of updating the laboratory support of educational institutions clearly demonstrate of its practical implementation' feasibility. Positive consequences from the implementation were identified as constant improvement of laboratory equipment, increase in the educators’ level, transformation of virtual distance learning based on lectures and videos into real learning with "live" visual demonstration of physical, chemical, biological and other processes and experimental research. As a recommendation, should wish that at the state level to recommend the implementation of this approach and to propose some legal mechanisms to overcome identified problems. Research limitations/implications: The present study was conducted for Ukrainian educational institutions with the involvement of foreign students from different countries studying in Ukraine. Practical implications: The introduction of a new concept into the educational process in countries with a weak economy will improve the educational quality and reduce the cost of creating laboratory support. Originality/value: Equipment should not only be a teaching tool, but also a teaching subject.