Johnson Matthey Technology Review - Fast Track

Abstract: In order to systematically sort out the current research status, application areas, and development direction of ozone in environmental catalysis, a bibliometric analysis of the relevant literature published in the Web of Science database from 2005 to 2025 was carried out. VOSviewer and CiteSpace software were utilized to view data from 1379 journal articles. Data visualization and analysis identified 5330 authors, 249 journals, and 1276 institutions. The results show that the number of publications in the field of ozone-related environmental catalysis is on an increasing trend, especially after 2017. China, Spain, the United States, Iran, and India are the main driving forces, with China being the most active country. The Chemical Engineering Journal and the Journal of Hazardous Materials are the journals that publish the most relevant research. Harbin Institute of Technology, University of Engineering and Technology Lahore and Beijing Forestry University are the three institutions that publish the most literature. Currently, a more complete theoretical framework and research methodology on ozone environmental catalysis have been developed worldwide. However, the research network is too centralized, with fewer frontier peripheral branches. The research focus has gradually shifted from the early direct oxidation of ozone to the design of catalytic materials, radical modulation and multi-technology coupling (photocatalysis, plasma), and in recent years, more attention has been paid to the synergistic degradation of complex pollutants (antibiotics, VOCs) and the optimisation of the green and sustainable processes. It is necessary to overcome the bottlenecks of catalyst stability, energy consumption and by-product control, and promote the scale-up of ozone catalysis technology in water treatment and air purification. The present study is of great importance for a better understanding and further supporting the research of ozone environmental catalytic processes.

The increase in population and need for energy in the world's fastest developing economies like India, make it critical to increase the supply of energy and augment its utilization. According to most of the energy projections, the expected future global and current demand patterns of energy are not sustainable. Thus, India will soon run out of its non-renewable energy sources. As per the study analysis, India receives 657.4 MW of solar radiation which when converted to power can be utilized to attain the energy demand of India. Solar hotspots represent geographical areas that receive abundant solar energy and offer significant prospects for commercial energy generation. Our study reveals that approximately 58% of India's geological zones qualify as sun-based hotspots. Furthermore, we propose an economically viable setup of solar plants based on the identified hotspots. To analyze these solar hotspots in India, we have employed a density-based 3-D clustering approach. In our research, we have substantially enhanced the efficiency of the 3-D DBSCAN spatial clustering method by incorporating KD-Trees and spatial indexing for 3D data. We conducted a comparative analysis between two techniques: 3D DBSCAN using the Euclidean distance as the distance metric and 3D DBSCAN Spatial clustering with KD-Trees as the distance function, aiming to optimize nearest neighbor searches. Our analysis demonstrates that, particularly when evaluating solar hotspots, utilizing 3D DBSCAN spatial clustering with KD-Trees yields more accurate results, especially when considering statistical parameters like the Silhouette Score and Dunn Index.

Currently, the traditional hydrodesulfurization (HDS) process is extensively utilized in oil refining industry for removing of sulfur compounds from petroleum fractions which have worst environmentally and healthy effects behind the low products quality. HDS process needs to high pressure and temperature, costly hydrogen gas, and it has low activity towards extract of thiophene and its derivatives. Alternative desulfurization processes like catalytic oxidative desulfurization (ODS) is one of the auspicious approaches because of its mild process conditions, no need for hydrogen, and efficient in removing of thiophenes and its derivatives. ODS process is developed with using various types of catalyst, oxidant (OX), and design of reactors used under different conditions of operating. In continuation with developing more workable and economical parameters in ODS technology, different types of reactors were considered in ODS technology as alternative for the traditional batch reactors. This work investigates the most recent developments in the used reactors for ODS process and reviews the advantages, limitations, and future potential of each reactor. A full comprehensive details were studied for reach reactor design, with the utilized parameters in the ODS technology, the oxidizing agents, and catalysts. The oscillatory baffled reactor (OBR) one of the most promising reactors for ODS process due to high proven sulfur removal efficiency and improving mass and heat transport steps through the oxidation reaction.

Abstract: This review delves into the production of sustainable aviation fuels derived from biomass and residual wastes through pyrolysis. The article addresses the challenges associated with the pyrolysis of wastes and provides an overview of both conventional and emerging pyrolysis technologies. The diverse forms of biomass and its significant economic benefits on a global scale. The underlying reason for it is the establishment of widely acknowledged renewable and sustainable energy sources. Approximately half of the global population relies on biomass as their primary energy source. Generating energy, heat, and electricity is a highly important source. The minimal levels of environmental pollution have facilitated the utilization of biomass as a sustainable energy source in recent technological advancements. Three types of biomass energy are biogas, bio-liquid, and bio-solid. In the domains of transportation and energy, it can serve as a substitute for fossil fuels. The primary focus of this study is to examine the data, explore the potential of biomass, and analyze the mechanisms of pyrolysis carried out using various processes, technologies (such as pyrolysis speed and temperature), and different types of reactors to produce bio-oil. This text also examines the current state and forthcoming obstacles of the pyrolysis process. In addition to the diverse array of pyrolysis byproducts. Based on this research, it can be inferred that the characteristics of pyrolysis products are influenced by the diversity of the materials utilized. Furthermore, pyrolysis products, such as bio-oil, have the potential to make a lucrative contribution to the expanding economy. To overcome future problems, further exploration is ultimately necessary. The primary factors of significance in pyrolysis technology are government subsidies and scientific advancements. The discussion emphasizes the significant barriers posed by the energy efficiency and capital costs involved in converting biomass and residual wastes into aviation fuels, hindering widespread adoption. To meet the aviation industry's greenhouse gas reduction targets by 2050, there is a pressing need for further advancements in technology development, highlighting the critical role of advanced technologies in overcoming these barriers.

Abstract: The Ćuk converter is extensively utilized across various applications for its capability to handle a wide range of input voltages and efficiently perform both voltage step-up and step-down conversions. However, the presence of parasitic elements, such as inductor winding resistance, capacitor equivalent series resistance (ESR), and losses in switches and diodes, significantly impacts the converter's performance, stability, and efficiency. This paper addresses these challenges by analyzing the effects of non-idealities in Ćuk converters operated under closed-loop voltage mode control. A detailed mathematical model of a 12 V to 24 V Ćuk converter is developed to evaluate the influence of parasitic elements and their interactions within the control system. This model provides valuable insights into the complexities introduced by these non-idealities and serves as a foundation for designing more resilient control strategies. To ensure output voltage stability and improved dynamic performance, a PID controller is employed with parameters optimized using the Ziegler-Nichols tuning method. The proposed control strategy is validated through MATLAB simulations, showcasing its effectiveness in countering the adverse effects of parasitics. The results indicate a stable operation with a steady-state error of less than 1%, a peak overshoot of 6.31%, a rise time of 6.21 ms, and a settling time of 37.4 ms. This work contributes to enhancing closed-loop voltage mode control strategies for non-ideal Ćuk converters, offering practical solutions to improve their reliability and efficiency in real-world applications.

By combining formulas known from the literature that relate thermoelectric parameters, the expression n≅1.13∙10¹⁹e^Sr-2/r_H(e^Sr-2-0.17) is obtained. That is, the  concentration of charge carriers can be determined using the Hall resistance and reduced Seebeck coefficient. Since these two parameters are calculated using the Seebeck coefficient, this coefficient is sufficient to determine the  concentration. To demonstrate the use of the obtained new formula, experimental data on SiGe thermoelectric are discussed.