Technologica Acta - Scientific/professional journal of chemistry and technology

Analysis of the representation of EE-devices as potential EE-waste in the area of the cities Bihać and Ključ

Fatima Muhamedagić, Belma Hodžić, Osman Perviz, Merjem Huskić, Mehmed Cero — Sat, 27 Apr 2024 00:00:00 +0200

EE-waste nowadays, as a consequece of the digital revolution and modern way of life, has become, among others, a big problem and at the same time a danger for the environment and the population. However, the fact is that quality management of EE-waste is a very profitabile activity. This waste is used as a high-quality secondary raw material in various production processes. The objectives of the research within this work for the cities of Bihać and Ključ were to determine: the total amount tf EE-devices; percentage representation of the three most represented/leastrepresented devices; total weight of EE-devices as a potential waste; the total amount of EE-waste per household and estimete the annual amount of EE-waste per inhabitant. To realize the goals, survey and comparison method were used. The results of the research showed that in the area of cities of Bihać and Ključ the quantitative representation (about 1 775 pieces); the percentage representation (mobile phones and TV) and the average age (about 5 years) of EE-devices were approximately the same. The differences were in the total weight of EE-devices as potential waste (38 853 – 39 316.4 kg); the total amount of EE-waste (5 942.9 –6 971.7 kg) and the annual amount of potential EE-waste (0.12 and 0.35 kg/inhabitant).

Microbiological quality of bottled water in freestanding dispensers

Sat, 27 Apr 2024 00:00:00 +0200

Nowadays, bottled water has become part of the lifestyle, replacing tap water, and water from freestanding dispensers is increasingly being used. The main goal of this research was to determine the health suitability of bottled water in freestanding dispensers. The research included the microbiological analysis of a total of 100 samples of bottled water from freestanding dispensers. The samples were mostly taken in the wider area of the city of Doboj (doctor's offices, shops, public buildings), and one dispenser in the city of Tuzla. Water samples were taken twice, in the period from April to June 2022. Water samples from 6 different manufacturers (Vivia, Kristal, Nevra, Gora, Aqua doria, Aqua team) were analyzed. 9% of water samples (9/100) were microbiologically correct. Microbiologically defective samples contained a higher total number of bacteria at 22°C and 37°C, as well as a higher number of coliform bacteria than the maximum allowed values. No significant differences in microbiological quality were found between older and/or recently installed water dispensers, as well as in terms of environmental conditions, while visible differences were observed between dispensers that were regularly hygienically maintained.

Antioxidant capacity and total phenol content in chokeberry (Aronia melanocarpa L.) juices from Bosnia and Herzegovina

Sat, 27 Apr 2024 00:00:00 +0200

In addition to their undeniable importance for industry, natural plant products are widely used in the production of functional food, which, in addition to satisfying nutritional properties, also exhibits certain pharmacological and physiological effects on human health. Chokeberry fruit and products are considered to be excellent sources of polyphenolic compounds. A large part of polyphenolic compounds from aronia berries is found in the juice, but the flesh of the berry that remains behind in the juice production process is also rich in these bioactive compounds. The aim of the conducted research was to examine the content of total phenols and antioxidant capacity in chokeberry juices grown in the territory of Bosnia and Herzegovina, as well as the possible correlation of the parameters. The antioxidant capacity of chokeberry juice in this study was determined by the FRAP method, and the total phenol content by the FC method. Tests were carried out in other juices for the same parameters in order to compare the obtained values. The research results show that the values of antioxidant capacity and total phenols in chokeberry juices vary (20-63 mmol Fe II/L; 850-4930 mg GAE/L), but are significantly higher than in other analyzed juices (7-25 mmol Fe II/L; 220–1265 mg GAE/L). By comparing the content of total phenols and antioxidant capacity in pasteurized and unpasteurized chokeberry juice samples, it can be concluded that they are higher in the sample prepared by the pasteurization process. Statistical parameters show that the linear correlation between the content of total phenols and the antioxidant capacity of chokeberry juices (r=0,964 ; p ˂0,001 ) and other analysed juices (r=0,960 ;p ˂0,001 ) is statistically significant.

Application of the principles of green chemistry in the plastic recycling industry: a case study

Sat, 27 Apr 2024 00:00:00 +0200

The subject of this research was to verify the feasibility of implementing green chemistry principles within the business company „Omorika Reciklaža“ Ltd. situated in Johovac near Doboj, Bosnia and Herzegovina. The objective of this study was to conduct a detailed assessment of the company's facilities and operations, using environmental audits, to identify technological processes (production lines), energy and waste flows, capacities, product range, and other pertinent factors crucial for the application of green chemistry principles. Special emphasis was placed on analyzing each substance that constitutes a raw material, whether used individually or as part of mixtures. The assessment of safety data sheets involved utilizing the CAS registration numbers of substances from the Chemical Abstracts Service, cross-referenced with the ECHA database (European Chemicals Agency). The outcomes, attained through an exhaustive analysis of each substance, were presented as a "chemical inspection" of the company. Through the analysis of all substances and mixtures in the technological process (chemical inspection), as well as the capacity of production flows, energy and resource flows, wastewater, and waste, the potential for enhancing the technological process was identified. This involved reducing dust levels in the workspace, decreasing electricity consumption (utilizing renewable sources), and substituting particularly hazardous chemicals used in the technological process.

The influence of potassium chloride and magnesium chloride on the color and sensory properties of cooked cheese

Suzana Jahić, Sebila Rekanović, Samira Hotić, Husein Vilić — Sat, 27 Apr 2024 00:00:00 +0200

The aim of this paper is focused on reducing sodium chloride content by partial replacement with potassium chloride and magnesium chloride in cooked cheese samples. For the production of cheese, standardized cow's milk from a domestic market producer was used, and the cheese was produced by heating the milk to a temperature of 95°C and coagulation with acetic acid. The one salted only with NaCl was designated as the standard sample, and the other samples were salted with combinations of salts in which NaCl reduction was performed: sample A1 had a ratio of 15% KCl:85% NaCl, sample A2 30% KCl:70% NaCl, sample B1 15% MgCl₂:85% NaCl and sample B2 30% MgCl₂:70% NaCl. The cheese samples were stored at + 4°C and color parameters and sensory properties were analyzed on the 1^st, 3^rd and 5^th days of storage. Based on the performed analyses, it was concluded that it is completely acceptable to replace sodium chloride with potassium chloride in the ratio of 15% KCl:85% NaCl. It is acceptable to replace sodium chloride with potassium chloride in the ratio of 30% KCl:70% NaCl, with the note that on the 5^th day of storage there is a gradual deterioration of the sensory properties compared to the samples analyzed on the 1^st day of storage. Replacing sodium chloride with magnesium chloride in the ratios 15% MgCl₂:85% NaCl and 30% MgCl₂:70% NaCl is not acceptable and is not recommended in the production of cooked cheeses due to the appearance of a metallic and bitter taste that is present in cheese samples from 1^st to 5^th days of storage.

Natural rubber composites with hydrochar as a partial filler: investigation of kinetic parameters

Sat, 27 Apr 2024 00:00:00 +0200

Reducing the environmental impact of the rubber industry has emerged as a major challenge, and one potential solution that has garnered significant attention is incorporating hydrochar as a partial filler in natural rubber composites. Hydrochar was obtained through hydrothermal carbonization treatment of hardwood waste biomass, and it has been found to have potential as a sustainable alternative to traditional filler carbon black. The aim of this study was to investigate the effect of varying hydrochar and carbon black content in natural rubber composites, while keeping the total filler amount constant at 50 phr. The study's findings indicated that higher hydrochar content resulted in a greater curing activation energy, facilitating the manufacture of larger natural rubber vulcanizates that required extended curing periods at reduced temperatures. The rubber industry's stringent environmental regulations have created a pressing need for sustainable alternatives, and incorporating hydrochar as a partial filler could offer a promising solution by repurposing waste materials into a valuable component for rubber composites.

The Role of Fishing Ports in the Sustainable Blue Economy

Gorana Jelić Mrčelić, Luka Živanović, Vedrana Nerlović — Sat, 27 Apr 2024 00:00:00 +0200

Fisheries and aquaculture play an important economic, environmental and social role. The development of fisheries and aquaculture depends on many factors, including adequately equipped ports and landing sites. The aim of this paper is to highlight the role of fishing ports in the sustainable blue economy. Fishing ports support the sustainable development of fisheries and aquaculture by promoting best practises for environmental protection, maintaining food quality, creating fair prices, supporting workers' rights, integrating local communities and ports, and more. The FAO Blue Ports Initiative aims to strengthen the role of ports as drivers of sustainable development in coastal communities and promote the achievement of several key Sustainable Development Goals (SDGs), including SDG 1 (No Poverty), SDG 2 (Zero Hunger), SDG 3 (Good Health and Well-being), SDG 5 (Gender Equality), and SDG 14 (Life Below Water). However, ports are also encouraged to adopt a blue economy approach to management to achieve long-term benefits for local communities. Port management, in collaboration with scientists, policy makers, the private sector, and civil society, should focus on inclusivity, competitiveness, greening, and process efficiency, and support collaborative actions to improve the quality of life of local communities.

The Potential of Bryophytes in Phytofiltration of Heavy Metal Contaminated Water

Adina Ćosić, Franc Andrejaš, Mirsad Džambić, Namir Halilović, Nevres Hurić — Sat, 27 Apr 2024 00:00:00 +0200

Bryophytes are a group of plants vital to many ecosystems and biogeochemical cycles and are well known bioindicators and biomonitoring tools. However, they have been deemed industrially less important than vascular plants and their potential for applications other than as biomonitoring tools has been overlooked. In recent years, however, bryophytes, and in particular mosses, are starting to gain attention as viable phytoremediation agents. Studies indicate that some moss species have the ability to uptake heavy metals such as Pb, Cd, Zn, Cu, As, and Cr from contaminated water. Tested mosses could both adsorb and absorb significant amounts of specific heavy metals without adverse effects on the plant. Results suggest that moss biomass, either dry or wet, could be used as a bio-sorbent in filtration of heavy metals. The review of available literature shows a promising prospect of moss to be used in phytofiltration of heavy metals. Existing knowledge on this topic could be the basis for further research which is needed

Interactive education on sustainable use of electrical devices

Jernej Frangež, Marko Jesenik — Sat, 27 Apr 2024 00:00:00 +0200

Education in GREEN electrical energy and production usage is essential for young people. Every consumer can do a lot if they use electrical devices wisely. This paper will present the design, intention and use of a didactical learning exhibit for middle and high school students during technical days on faculty and faculty promotions and for educational purposes. Our main goal is to introduce students to how some everyday electrical devices work, how much energy they use and how they can save as users. The most significant emphasis will be electromagnetic devices such as elevators and devices we use daily. We will use a professional approach and design for that purpose, but we will focus on presenting it on an interactive touchscreen and small examples of those devices. The content will be in graded expertise levels, from simple picture and animation calculations to the advanced picture and mathematical model presentations. The exhibit will be designed modularly so that content or presentation can change quickly and be made from recycled or sustainable materials as much as possible.

Perception of faculty of tourism and rural development students on slow food concept

Maja Ergović Ravančić, Valentina Obradović, Helena Marčetić, Svjetlana Škrabal — Sat, 27 Apr 2024 00:00:00 +0200

The Slow Food movement, originated in Italy in 1989, is a movement that defines a respectful attitude towards food. It includes the protection of local food, food culture and traditions. The movement advocates the cultivation of food that is carefully prepared and consumed with pleasure. It encourages the improvement of relations between producers of ecologically produced food, cooks and consumers. Slow Food represents resistance to fast food and modern fast consumption, which has led to the abandonment of local gastronomic traditions and a decrease in people's interest in authentic food.

The aim of this paper was to investigate the attitudes of students of the Faculty of tourism and rural development in Požega about Slow Food. Using the online survey method, the research has been conducted on a sample of 38 students of Enogastronomy and Tourism.

The results of the research showed that students are aware of the concept of Slow Food. Enjoying the food they consume is extremely important for almost all students. Half of the respondents had heard of Slow Food, while only a quarter declared that they had consumed food presented as Slow Food. According to the respondents, Slow Food is best described by the attributes "natural", "ecological", "healthy", "conscious food consumption" and "enjoying eating".

Determination of physical and chemical parameters of water before and after ion exchange treatment

Sat, 27 Apr 2024 00:00:00 +0200

In accordance with consumer requirements, the water must be adequately purified, and the
corresponding parameters within the defined values. Various methods are used for this
purpose, of which the ion exchange method can be highlighted as the simplest, most efficient
and economically profitable. Ion exchange is a reversible process of ion exchange between a
solid phase and an electrolyte solution. The ion exchanger is a macromolecular insoluble
material that has chemically bound electrified groups and mobile, oppositely charged ions that
compensate for this electrification. Ion exchangers are usually used in the form of compact or
granular beds that fill the column through which the solution with the ions to be exchanged
flows.
They usually contain phenolic, carboxylic, sulfonic amino and other groups, which is why the
treatment also results in decarbonization, softening, demineralization and denitrification of
water. As the assessment of water quality is based on the most significant physico-chemical
parameters, the aim of the work is the analysis of drinking water before and after treatment
with an ion exchanger. For this purpose, organoleptic and physico-chemical parameters were
analyzed: pH values, electrical conductivity, m-alkalinity, p-alkalinity, water hardness,
organic matter content, chloride content, iron and manganese content. An ion exchanger based
on resin was used, which after use was regenerated by washing with NaOH solution.
The results of the analysis showed that all the values of the analyzed parameters are in
accordance with the Rulebook on the Healthiness of Drinking Water (Official Gazette of
Federation of Bosnia and Herzegovina No. 40/10), and that the water treatment was
effectively carried out, which classified the water as hard water and classified it as soft water.
Key words: water, ion exchange, physical-chemical parameters; water treatment.

Determination of the biomethane potential of different types of manure from extensive animal farming

Sat, 27 Apr 2024 00:00:00 +0200

Livestock production is a potential environmental pollutan because of the high concentartions of animals on the small area. Production of biogas with anaerobic degradation from organic waste is one of the pledge alternative energetic solutions, especially from organic manure made from animal farming and other residuals of agricultural production.

The aim of this paper was to determine posibillity of using manure different origin from extensive animal breeding for production of biogas in labaratory conditions. The results obtained will be based on posibillity of use waste streams from extensive animal husbandry as basic substrate for anaerobic digestion.

In this regard, cosubstrates were formed as mixture 1 chicken excrement; mixture 2 sheep manure; mixture 3 cow manure; all three basic substrates were in mixture with the sludge from the wastewater treatment plant. The results showed production of 71,5 ml CH₄/gVS for mixture 1, 68,65 ml CH₄/gVS for mixture 2 and 48,68 ml CH₄/gVS for mixture 3.

Antimicrobial and cytotoxic activities of essential oil from the aerial parts of Pulicaria dysenterica (L.) Bernh. (Asteraceae)

Sat, 27 Apr 2024 00:00:00 +0200

The chemical composition of Pulicaria dysenterica (L.) Bernh. aerial parts essential oil (EO), growing wild in Bosnia and Herzegovina, was presented in the study. Biological activities of the EO was included antimicrobial investigation and cytotoxicity. Antimicrobial activity was determined on selected ATCC strains of microogranisms while cytotoxicity was recorded on HeLa cell line. The aerial parts of P. dysenterica contained 0.3% of yellow, liquid, fragrant EO. The identified 51 constituents accounting for 81.09% of the oil. The EO was characterized by the presence of a high concentration of oxygenated sesquiterpenes 51.83% while oxygenated monoterpenes constituted 15.57%, sesquiterpene hydrocarbons 9.32% and non-terpene compounds presented 4.37% of EO. The dominant compounds were sesquiterpenes caryophyllene oxide, (E)-nerolidol, β-caryophyllene and monoterpene nerol. Antimicrobial activity of EO was tested against bacteria Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli, as well as against fungus Candida albicans. Results indicated that all used the microorganisms were sensitive to the EO. It has observed promising results against bacteria Escherichia coli with MIC value 1 x 10³ µg mL^-1. The oil showed moderate cytotoxicity against HeLa cell line using MTT method with IC₅₀ of 188.52 μg mL^-1. These results support traditional use EO in the treatment of diarrhea and dysentery and as insecticide.