Raw Materials Research Articles

СТЕНОВЫЕ МАТЕРИАЛЫ ПОЛУСУХОГО ПРЕССОВАНИЯ НА ОСНОВЕ ГРАНУЛИРОВАННЫХ ИЗВЕСТНЯКОВЫХ ОТХОДОВ КАМНЕДОБЫЧИ

this article is devoted to the study of the processes of granulation of raw materials mixtures from limestone waste of stone mining and Portland cement and the production of wall materials based on them by semi-dry pressing. The optimal humidity-time parameters of the manufacture of granules were determined, laboratory samples of wall materials from granular mixtures with different contents of Portland cement were made. It was found that the compressive strength of samples from granulated raw materials exceeds the strength of samples from non-granulated raw materials by 3-12%. Subject of research: semi-dry pressed wall materials based on granular limestone waste from stone mining Materials and methods: Nummilite limestone waste from the Skalistoe deposit (Crimea) and Portland cement PC 500 DO from the Novorossiysk Cement Plant were used for the study. The physical and mechanical properties of the prototypes were determined by standard methods. Results: Experiments have shown that the compressive strength of samples made from granules containing 5-15% Portland cement and 85-95% of stone mining waste exceeds the strength of samples from non-granulated raw materials by 3-12%. Conclusions: The use of granular limestone waste from stone mining as the main component for the production of wall materials by semi-dry pressing makes it possible to increase their strength characteristics. The addition of Portland cement in certain proportions (5-15%) improves the strength characteristics of materials. Further research can be aimed at optimizing the composition of materials, studying their durability and adapting the production process to industrial scales.

Recent Development of Functional Bio-Based Epoxy Resins

The development of epoxy resins is mainly dependent on non-renewable petroleum resources, commonly diglycidyl ether bisphenol A (DGEBA)-type epoxy monomers. Most raw materials of these thermoset resins are toxic to the health of human beings. To alleviate concerns about the environment and health, the design and synthesis of bio-based epoxy resins using biomass as raw materials have been widely studied in recent decades to replace petroleum-based epoxy resins. With the improvement in the requirements for the performance of bio-based epoxy resins, the design of bio-based epoxy resins with unique functions has attracted a lot of attention, and bio-based epoxy resins with flame-retardant, recyclable/degradable/reprocessable, antibacterial, and other functional bio-based epoxy resins have been developed to expand the applications of epoxy resins and improve their competitiveness. This review summarizes the research progress of functional bio-based epoxy resins in recent years. First, bio-based epoxy resins were classified according to their unique function, and synthesis strategies of functional bio-based epoxy resins were discussed, then the relationship between structure and performance was revealed to guide the synthesis of functional bio-based epoxy resins and stimulate the development of more types of functional bio-based epoxy resins. Finally, the challenges and opportunities in the development of functional bio-based epoxy resins are presented.

A Systematic Literature Review of Existing Methods and Tools for the Criticality Assessment of Raw Materials: A Focus on the Relations between the Concepts of Criticality and Environmental Sustainability

Critical raw materials have significant economic and social impacts across numerous sectors. Numerous artifacts have been developed to assess their criticality. However, there is no univocity around the factors determining criticality. A systematic literature review was conducted to consider all academic works and official reports on criticality assessment. The review aimed to classify these artifacts to provide a clear picture of the heterogenous literature, with a focus on the relationship between criticality and environmental sustainability. Works proposing or updating criticality assessment artifacts were included according to the eligibility criteria. Academic sources were drawn from the Scopus Database in 2023. Official reports included those considered seminal by academic literature. The risk of bias in the selection and classification of the 162 works was low, as the review sought to be comprehensive. The included artifacts are systematically classified. A mapping of the identified criticality assessment tools and methods has been developed. The review found that while environmental impacts are considered in several works, the theoretical connection between criticality and environmental sustainability is weak. Three perspectives on this relationship are identified and discussed. The main limitation of this study is the inability to analyze undisclosed artifacts. It was conducted under the Horizon Europe Programme (Grant Number 101091490).

From Conventional to Craft Beer: Perception, Source, and Production of Beer Color—A Systematic Review and Bibliometric Analysis

Beer is a popular beverage consumed globally, and studies have emphasized the benefits of moderate consumption as well as its sensory effects on consumers. Color is a crucial sensory attribute, being the first aspect a consumer notices when assessing a beer’s quality. This review seeks to offer detailed insights into how brewing methods, raw materials, and the chemical diversity of beer influence the production of beer color. The chemical mechanisms responsible for color development and how consumers and color systems perceive the color of beer were assessed. A systematic review following the PRISMA methodology, coupled with a bibliometric analysis, was performed using (Rayyan 2022) and (VOSviewer 1.6.20) software to assess and evaluate the scientific research retrieved from the Web of Science Core Collection. The findings highlight the significant roles of malt types, heat brewing processes, control of chemical parameters, and innovative brewing techniques in conventional beer color production. Novel chromophores like perlolyrine, pyrrolothiazolate, and furpenthiazinate are thought to affect Pilsen-style beers, along with melanoidins, Strecker aldehydes, and 5-hydroxymethylfurfural (HMF) in conventional beers. In craft beers, such as fruit- or herb-based beers, flavonoids like anthocyanins, along with other natural pigments and synthetic colorants, are identified as the primary sources of color. However, studies related to the influence of chromophores like perlolyrine, pyrrolothiazolate, and furpenthiazinate on beer color are scarce, and emerging additives, such as pigments from microorganisms, spices, exotic herbs, and leaves of plants, on craft beer offer insights for future research.

A global fairtrade partnership needed to address injustices in the supply chains of clean energy technology materials

Abstract Renewable sources produced close to one-third of the world’s electricity in 2023. However, a limited but growing body of research suggests rapid renewable energy development is leading to conflict and resource exploitation in energy-transitioning communities. Such injustices are attributable to the extractivist nature of renewable energy development, where raw materials, also known as Clean Energy Technology Materials (CETMs), are in limited quantities and often concentrated in resource-constrained zones in the Global South. In this perspective, we call for an urgent need for energy justice considerations in CETM’s supply chain. We used demand projection data from 2020 to 2040 to look into the effects of important CETMs like nickel, cobalt, and lithium on distributive justice. We also examined the potential of these effects to tackle systemic injustices such as conflict, labor exploitation, and transactional colonialism. Next, we analyzed global mining production data from the United States Geological Survey using a CETM life cycle lens and found that increasing demand for these materials is exacerbating restorative injustices, particularly in the Global South. Finally, building on the above evidence, we called for the creation of multi-stakeholder partnerships and the establishment of fair trade standards across the critical CETM supply chain. Graphical abstract Highlights Here, we analyzed the projected demand growth for selected clean energy technology materials by 2040 relative to 2020 levels using data from the International Energy Agency, visualized their global mining production using data from the United States Geological Survey, explained how the demand for these materials is exacerbating certain injustices, and recommended multi-stakeholder partnerships across the supply chain of these materials. Discussion The rapid growth of renewable energy technologies is creating injustices throughout the supply chain of clean energy technology materials (CETM). A lack of any energy justice framework across CETMs’ extraction, processing, decommissioning, and recycling is exacerbating restorative injustices, especially in the Global South. By examining the projected demands and geospatial patterns for the extraction of minerals, metals, and other materials essential for clean energy technology development, the inequities faced by impoverished, marginalized, and Indigenous communities become apparent. We argue that if coffee can have fair trade standards across its supply chain, why can’t we have similar considerations for the CETMs? There is a need to include transparency in the sustainability, ethics, and energy efficiency of CETM extraction and processing through global partnerships across its supply chain.

Box-Behnken design (BBD) for optimization and simulation of biolubricant production from biomass using aspen plus with techno-economic analysis

The growing concern and limitations for existing lubricants have driven the need for biolubricants, extensively proposed as the most suitable and sustainable lubricating oils. Biolubricant refers to lubricants that quickly biodegrade and are non-toxic to humans and aquatic habitats. Over the last decade, there has been a significant increase in the production of biolubricants due to the rising demand for replacing petroleum-based lubricants with those derived from renewable sources like vegetable oils and lipase that are used in various applications. In this study biodiesel (FAME) produced from blending animal fats and waste cooking was used as a raw material with ethylene glycol for biolubricant production using a transesterification reaction in the presence of calcium oxide which considers the newest and novel part as there is no production of biolubricant from animal fats and waste cooking oil in previous researches. The reaction parameters of biolubricant production were optimized using response surface methodology (RSM) with the aid of Box Behnken Design (BBD) to study the effect of independent variables on the yield of biolubricant. These variables are temperature ranging from (100–150 °C), reaction time ranging from 1 to 4 h, and FAME (Fatty Acid Methyl Ester) to alcohol molar ratio ranging from (2:1) to (4:1). The highest biolubricant yield is 91.56% at a temperature of 141 °C, a FAME/alcohol molar ratio of 2:1, and 3.3 h. Various analyses were performed on the produced biolubricant at the optimum conditions. The results include a pour point of -9 °C, a flash point of 192 °C, a kinematic viscosity at 40 °C of 10.35 cSt, a viscosity index of 183.6, an ash content of 0.76 wt.%, and a carbon residue of 1.5 wt.%, comparing favorably with the ISO VG 10 standard. The production process of biolubricant was simulated with Aspen Plus version 11 using a Non-Random Two-Liquid (NRTL) fluid package. The simulation results indicated that the production process can be applied on an industrial scale. Economic analysis was performed on the biolubricants production plant. The total capital investment was $12.7 M with a payback period of 1.48 years and an internal rate of return (IRR) of 67.5% indicating the suitability and profitability of the biolubricant production.

Design, synthesis, and characterization of novel copolymer gel particles for water-plugging applications

Abstract Multi-stage plugging represents a promising strategy for enhancing production and injection rates in medium-and low-permeability oilfields. Despite its potential, the efficacy of current plugging agents, particularly hydrophobically bonded water-soluble polyacrylamide-based gel microspheres, is hindered by notable drawbacks such as low stability and inadequate compressive strength. Therefore, a comprehensive understanding of water plugging mechanisms coupled with the optimization of gel microsphere properties is essential for advancing the development of gel-based plugging agents with superior characteristics or intelligent regulatory capabilities. The P(AA-AM-[PrSO3]Vim) ionic liquid copolymerized gel particles were designed and synthesized by using microfluidic technique and titration gel method with AM, acrylic acid (AA), 1-vinylimidazole (Vim) and 1,3-propylsulfonyl lactone (PrSO3) as the raw materials. The morphology and structure of the copolymer gel particles were characterized, and the effects of [PrSO3]Vim and cross-linker content on the water-absorbing properties and strength of the gel particles were investigated. When the amount of [PrSO3]Vim was 12%, the concentration of crosslinker was 1.5%, and the temperature was 40°C, the water absorption capacity reached the maximum value of 163 g·g−1. The strength of the P(AA–AM–[PrSO3]Vim) spherical gel particles was maximized at a [PrSO3]Vim content of 4%. Furthermore, the chemical and physical roles of the P(AA–AM–[PrSO3]Vim) spherical gel particles were studied in a typical water-plugging environment. This study provides experimental data and a theoretical basis for the application of functional spherical gel-plugging particles in current oilfield environments.

STUDIES ON THE SYNTHESIS AND CHARACTERIZATION OF ZEOLITES AND THEIR APPLICATION AS A CATALYST

Because of their wide range of uses in catalysis, adsorption, and ion exchange, zeolites, which belong to the family of microporous aluminosilicate minerals, have garnered a lot of interest in recent years. The synthesis and characterisation of a variety of zeolites, as well as their potential application as catalysts in certain industrial processes, are the primary objectives of this research. Following the hydrothermal synthesis of various zeolite structures, such as ZSM-5, Y-zeolite, and Beta-zeolite, using a variety of templates and raw materials, followed by the structural and chemical characterization of these zeolite structures using techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR), the research is being conducted. In order to evaluate the effectiveness and selectivity of the produced zeolites in comparison to traditional catalysts, their catalytic activity is examined in a number of different processes, such as cracking, isomerization, and alkylation. The findings indicate that the particular pore structure, surface area, and acidity of the zeolites have a substantial impact on the catalytic activity of the zeolites. In addition, the catalytic capabilities of zeolites can be further improved by modifying them by ion exchange or impregnation with metal nanoparticles (for example, platinum or lead). After doing the research, the researchers came to the conclusion that zeolites have the potential to be effective catalysts for a variety of chemical transformations that are also kind to the environment. These catalysts are interesting alternatives to traditional catalysts in industrial processes such as the refinement of petrochemicals and the creation of sustainable energy because of their adaptability, the fact that their characteristics may be tuned, and the fact that they can be recycled.

CONSTRUCTION WASTE RECYCLING ORGANIZATION

The purpose of the article is to study the global experience of organizing the collection and processing of construction and demolition waste for their reuse in construction, to determine the possibility of applying positive practices in Ukraine. In the EU, construction waste makes up more than a third of all generated waste. The components of construction and demolition waste have different resource values, but can still be easily recycled into new products or materials. The level of recycling and disposal of waste varies significantly in EU countries, ranging from less than 10% to more than 90%. With the economic development of the country, the volume of waste increases. The main obstacles that hindered the development of sustainable waste management, for example in Germany, are the lack of nationwide regulation of secondary construction materials; lack of economic incentives, when primary raw materials are presented in large quantities in most regions of Germany, and therefore they are relatively cheap compared to secondary raw materials; sanctions for violators of waste management rules are too low and not applied regularly. Ways to ensure the need to process construction waste can be the determination at the legislative level of the volume of construction waste depending on the area of the building where construction work is performed, or the cost of construction work; establishment of a direct requirement for the use of a certain percentage of products from recycled construction waste in new construction or a direct ban on landfills for construction and demolition waste that can be processed for reuse. Economic incentives, such as tax breaks or subsidies, as well as additional taxes on the use of non-recycled materials, are used to encourage companies to use secondary materials and reduce waste. The Waste Framework Directive, adopted in 2008, aims to prevent or reduce waste generation in order to transition to a circular economy and guarantee the EU's long-term competitiveness.

Social Distancing in an Interactive Approach: A Typology and Functions of Visual Representations of the Concept

The aim of the article is to analyze visual representations of the concept of social distancing on the basis of material retrieved from the Internet. The examples cited in the text primarily refer to verbal expressions and nonverbal signs operating in English-speaking countries. In the first part, we will introduce the reader to the broader context of the COVID-19 pandemic, which significantly changed the meaning of the term social distancing. In the next part, we draw on the theoretical work of Erving Goffman and analyze the practice of maintaining social distancing as a kind of interaction ritual. In the third part, we will place the concept of social distancing within the framework of Edward T. Hall’s proxemic research. The final section of our discussion will analyze visual images referring to social distancing featured on COVID masks and other artifacts. We also propose our own typology of these visual representations of social distancing and the functions they serve.

A new electrolyte for molten carbonate decarbonization

The molten Li2CO3 transformation of CO2 to oxygen and graphene nanocarbons (GNCs), such as carbon nanotubes, is a large scale process of CO2 removal to mitigate climate change. Sustainability benefits include the stability and storage of the products, and the GNC product value is an incentive for carbon removal. However, high Li2CO3 cost and its competitive use as the primary raw material for EV batteries are obstacles. Common alternative alkali or alkali earth carbonates are ineffective substitutes due to impure GNC products or high energy limitations. A new decarbonization chemistry utilizing a majority of SrCO3 is investigated. SrCO3 is much more abundant, and an order of magnitude less expensive, than Li2CO3. The equivalent affinities of SrCO3 and Li2CO3 for absorbing and releasing CO2 are demonstrated to be comparable, and are unlike all the other alkali and alkali earth carbonates. The temperature domain in which the CO2 transformation to GNCs can be effective is <800 °C. Although the solidus temperature of SrCO3 is 1494 °C, it is remarkably soluble in Li2CO3 at temperatures less than 800 °C, and the electrolysis energy is low. High purity CNTs are synthesized from CO2 respectively in SrCO3 based electrolytes containing 30% or less Li2CO3.

COMPARISON OF SOME QUALITY PARAMETERS IN SOUR CHERRY JUICE IN DIFFERENT PACKAGING

Fruits and their products are of great importance in the food industry. Fruit juices are found in almost every market, which helps consumers to get nutritional value from their consumption. The quality and insurance must be at the right level, but even more important to apply permanent control. Sampling was carried out randomly directly in the supermarket, and the analysis of parameters in the study of sensory quality (color, taste, aroma, and homogeneity) and physical-chemical (pH, °Brix, total acidity, and turbidity) in sour cherry juice is of importance because the same juice in different packaging is compared. After the analyses that have been carried out and the results obtained, they provide additional insight into the analyzed parameters. So, the consumer receives additional information, also confidence in the quality of the product will increase based on the results obtained. In conclusion, even though we are talking about the same sour cherry juice, as a result of the % content of the raw material with different amounts and the different packaging, the analyses for the parameters under study prove the differences, but at the limit, so the analyzed juices are within the standard for quality.

INVESTIGATION OF THE RHEOLOGICAL, NUTRITIONAL, AND SENSORY PROPERTIES OF THE GLUTEN-FREE BREAD PRODUCED FROM RICE, BEAN, AND CHICKPEA FLOUR

In recent years, the demand for gluten-free products has been constantly increasing due to the increase in the number of people suffering from celiac disease. Bread is the main product consumed in our country; therefore, gluten-free bread for celiac patients on the market is mostly of poor quality and low nutritional value, while gluten-free flour has a very high price. The purpose of this work was to investigate the rheological properties of dough, the nutritional value of bread, as well as the sensory properties of gluten-free bread produced from mixtures of raw materials such as rice, chickpea, and bean flour, corn starch, and egg powder. The results showed that the gluten-free bread had different rheological properties, and only mixes M5 and M6 had similar rheological properties, such as dough development, stability, and degree of softening, to the control bread M1. Gluten-free bread from mixtures M2 and M3 had higher contents of protein, fat, cellulose, and minerals, while bread from mixtures M5 and M6 had medium contents. Bread M2 and M3 had acidity levels above the allowed limits which made them unusable or had a short shelf life. Sensory analyses showed that bread M5 had similar sensory properties to the control bread M1 and fell into the same quality category; also, bread from the M5 mixture has a much better taste and aroma. For consumption, we recommend using gluten-free bread from the M5 mixture, which in its composition has 80% rice flour, 7.5% chickpea flour, 5% bean flour, and 7.5% egg powder.

STATE AND PROSPECTS OF THE DEVELOPMENT OF UKRAINE'S BUILDING INDUSTRY IN THE CONDITIONS OF THE ECONOMIC CRISIS CAUSED BY THE FULL-SCALE AGGRESSION OF THE RUSSIA, FROM THE POINT OF VIEW OF ECONOMIC CYCLICITY

The article is dedicated to examining the specific manifestations of economic cyclicality in Ukraine's building materials industry under martial law conditions. The analysis reveals that the full-scale war has led to the destruction of approximately 20% of enterprises, while others have experienced significant declines in production volumes, market access, raw material sources, and human resources. The features of war-induced economic crises are compared with cyclical overproduction crises, showing that military actions immediately push the economy into a recession phase. However, recovery may commence even before the end of hostilities due to the economy reaching the trough of the economic cycle.The article explores various approaches to defining and understanding the concept of "economic crisis," highlighting the importance of identifying its causes and characteristics. Key factors influencing the transition between different phases of economic cycles—recession, depression, recovery, and expansion—are identified. It is noted that the moments of phase transition are critical to economic development, as they represent the shift from quantitative changes in one phase to qualitative changes in the next.The dynamics of real estate prices are analyzed as one of the key indicators signaling the onset of the recovery phase. Additionally, the article formulates the components of a development strategy for Ukraine’s construction sector during the recovery period, taking into account the consequences of the war. These components include the localization of building materials production, improving housing comfort, ensuring the environmental sustainability of building materials, conserving resources in their production (particularly energy), involving foreign aid in the reconstruction process, and recycling demolition waste into building materials. It is determined that the future development of the construction industry must also address the issue of effectively insulating protective structures and bomb shelters with eco-friendly materials, necessitating further development of domestic building materials that meet the urgent demands of wartime. The article concludes with the prospect of utilizing hemp-lime building materials in the reconstruction process, as they fully align with the proposed development strategy

Assessment of the Impact of Pretreatment of Spent Coffee Grounds with Diluted Sulfuric Acid on the Efficiency of Methane and Lactic Acid Fermentation

Lignocellulosic materials are composed of three major biocomponents such as cellulose, hemicellulose and lignin, which form a compact lignocellulosic complex. Characterized by high caloric content, lignocellulosic biomass, including coffee grounds, is a valuable energy source that can be efficiently used in various bioconversion and biotransformation processes. Due to the high consumption of coffee in the world, there is an increasing amount of coffee grounds, which is a rich waste and at the same time a valuable secondary raw material, and its use fits perfectly into a closed-loop economy. Coffee grounds biomass contains polysaccharides, mainly mannans, proteins, lipids, polyphenols, which will allow the development of different biorefinery strategies, the creation of new value-added products with reduced waste generation. The research describes the pre-treatment of coffee grounds with dilute sulfuric acid to evaluate the effect of acid concentration, hydrolysis time on biogas yield, including methane and lactic acid biosynthesis during anaerobic fermentations. A yield of 381.12 mL of CH4/g-VS methane was obtained, accounting for 72.48% of the total biogas composition. It was found that the most efficient sample in terms of substrate pre-treatment for lactic acid biosynthesis was coffee grounds after 90 min hydrolysis with 1.5% H2SO4 at 121 °C.

История забытой экспедиции

This article delves into a little-studied aspect of the history of the Russian exploration of the North – one of the first Arctic expeditions of the Russians in the early XIX century. The appeal to the historical experience of the discovery and study of the New Siberian Islands archipelago is determined by the growing interest in it on the part of world powers in connection with the development of coastal shelf resources and the resumption of the Northern Sea Route. In the Russian historiography the name of M.M. Gedenstrom remained a figure of silence for a long time in comparison with such explorers as F.P. Wrangel, P.F. Anju, G.A. Sarychev, E.V. Toll, who were engaged in the study of this region of the Arctic. However, the expedition of M.M. Gedenstrom is marked not only by the connection with specific tasks of Russian foreign policy and attempts to solve scientific problems relevant for that time, but also with the interests of business development on the islands, the subsoil of which is still rich in valuable fossil raw materials. M.M. Gedenstrom was the first to create a general map of the Novosi-birsk Islands, described them and the coast between the mouths of the Yana and Kolyma rivers, and corrected inaccuracies on previously compiled maps.

Regulation of surface oxygen functional groups in starch-derived hard carbon via pre-oxidation: A strategy for enhanced sodium storage performance

During the process of sodium storage in hard carbon anodes, the significance of surface oxygen functional groups cannot be overlooked. In this work, we utilize starch as raw material to synthesize hard carbon by the process of pre-oxidation and two-step carbonization. XPS analysis reveals that pre-oxidation bolsters the presence of CO bonds, thereby providing more active sites. TEM analysis reveals that hard carbon with pseudo-graphite and graphite-like structure is obtained at relatively high carbonization temperature (1400 °C), and the formation of closed pores results in lower specific surface area. The introduction of appropriate oxygen-containing groups in pre-oxidation process can facilitate the cross-linking of starch chains, promoting the increase of defect sites and the sodium storage performance of hard carbon. A series of samples are prepared at various pre-oxidation temperature. Among them, P200-HC obtained after pre-oxidation at 200 °C and carbonization at 1400 °C exhibits the highest reversible specific capacity of 342.7 mAh g−1 at current density of 0.1 C with an initial Coulombic efficiency of 71.1 %, and capacity retention of 87.3 % at current density of 1 C. The work presents a viable approach for the synthesis of hard carbon derived from starch, thereby expanding the design tactic of sodium-ion batteries with improved performance.

Natural Rubber Latex Wastes from Balloon Production as Valuable Source of Raw Material: Processing, Physico-Mechanical Properties, and Structure

This study explores the potential for recycling natural rubber (NR) latex waste from balloon production through the devulcanization and revulcanization processes. The mechanical devulcanization of colored latex balloon waste was conducted, followed by revulcanization using a sulfur-based system. The reclaimed rubber’s properties, including crosslink density, tensile strength, and abrasion resistance, were compared with those of virgin NR. The results demonstrate that the reclaimed rubber maintains a crosslink density close to that of virgin NR. Hardness and abrasion resistance were comparable, indicating successful material recovery. Structural analyses, including FTIR and SEM microscopy, revealed that the devulcanization process effectively allowed for successful revulcanization. This study concludes that NR latex waste can be effectively recycled and reused in rubber composite formulations, offering a sustainable approach to waste management in the rubber industry and contributing to developing eco-friendly materials. In the context of this research, integrating advanced chemical and physical methods, such as solubility parameter calculations and enhanced devulcanization techniques, could further optimize the devulcanization process. These methods quantitatively enhance the efficiency of material recovery, offering a path to more sustainable recycling practices. The findings suggest that combining such advanced methodologies could significantly improve recycled NR latex’s overall performance and applicability in industrial applications.

Eco‐efficiency improvement strategies for disinfectants

AbstractDisinfectants are essential products for reducing health risks, but they also have significant environmental impacts. This study assessed the Eco‐efficiency of disinfectants based on the NBR ISO 14045:2014. Primary data were collected from Brazilian producers, while secondary data were obtained from patents and the Ecoinvent database. The system boundaries encompassed cradle‐to‐consumer use. The selling price was adopted as the product system value indicator (economic analysis). Raw materials production had the greatest impact on the environmental performance of disinfectants A (Antibacterial, surfactant and preservative) and C (Antibacterial, surfactant and opacifier). Disinfectant B, in addition to raw materials production (Antibacterial, opacifier and surfactant), also experienced significant impacts from consumer transport. These critical processes represent more than 60% of the overall impacts in both categories. The Eco‐efficiency matrix (profile) related environmental and economic indicators. All disinfectants occupied quadrants three or four, indicating high impact on the environmental categories. Disinfectant C had the highest Eco‐efficiency while disinfectant B had the lowest, mainly due to its product system value. Sensitivity analysis indicated environmentally viable changes in the products' composition, such as replacing the antibacterial, surfactant, preservative, and opacifier. Energy and water consumption did not significantly impact the assessed products.

EXAMINATION OF THE DYNAMICS OF ANALYZES PERFORMED FOR THE PRESENCE OF RADIONUCLEIDE RESIDUES IN FOOD IN THE PERIOD 2019-2023 IN THE REPUBLIC OF NORTH MACEDONIA

The main focus of this research is to determine the extent of analyzes performed for the presence of radionuclides in food, their dynamics, which radionuclides are present in food, and how much their radioactivity was in the period 2019-2023. The research covers the period from January 01, 2019. until December 31, 2023. The data we used to conduct this research were obtained from the Public Health Institute of R. N. Macedonia. The tests were carried out with accredited methods and by the Regulation on the maximum allowed amounts of radionuclides in food, water, air, land, products, and raw materials of animal and plant origin and objects for general use. Relative numbers and trends are used as statistical methods of work. According to the results, in the period 2019-2023, radionuclides were analyzed in 6065 samples (2711 samples from imports, and 3354 samples from domestic production). The largest amount of radioactivity analyzes were performed in the group of mushrooms (51%) and the group of grain and flour (44%). The scope of analyzes performed for the presence of radionuclide residues in food in R.N. Macedonia shows a downward trend. In the analyzed products, no radioactivity above the limit values was detected (except in 2020 when only in 1 product from the mushroom group - dry morel) detected a value for Cs-137 = 662.8 Bq/kg, and the maximum allowed value is 600 Bq/kg ). It can be concluded from the study that food is safe in terms of the presence of radionuclide residues, but work should be done to increase the volume of analyzes performed for the presence of radionuclides in food, as well as to increase the coverage of different groups of products (fruit, vegetables, coffee, tea, etc.) in which such analyzes would be performed.