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Modern production of vegetable oils has reached impressive levels, and the ever-growing quantities of waste cooking oil (WCO) provide a local source of raw materials for innovative materials. The WCO composite production process involves a series of reactions, including polymerisation, esterification, and transesterification, which lead to the hardening of composite materials. In light of the growing problem of bacterial and fungal diseases, materials with high strength properties and biocidal properties are being sought. Fungal infections of the skin are a widespread problem, and the number of cases is steadily increasing. This article presents a study of the antibacterial potential of WCO-based composites enriched with hops or sorrel root in the context of their application in the construction industry. The compressive and flexural strength of the oil composites, their absorbability and hydrophobicity, and their effects on Gram-positive (S. aureus and S. epidermidis) and Gram-negative (E. coli and P. aeruginosa) bacteria and fungi (A. niger, P. anomala) were investigated. Maximum split tensile strength (4.3 MPa) and flexural strength (5.1 MPa) were recorded for oil-hop composites. Oil composites enriched with curly sorrel and hops showed antibacterial activity against S. aureus at 27% and 25%. High biocidal activity (up to 70%) was recorded against E. coli and against S. epidermidis (up to 99%) due to the action of composites with curly sorrel. The antifungal activities of composites with hops was 15% and 19% for P. anomala and A. niger, respectively, while with curly sorrel they were 42% and 30%., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Staroń et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Currently, pathogenic microorganisms are becoming more active in public utility areas like parking lots and waste shelters due to the accumulation of organic waste. This uncontrolled waste leads to decay, altering its composition and presenting a microbiological risk to public health. Additionally, it emits unpleasant odors containing chemicals that irritate the mucous membranes, causing discomfort in the nose, throat, and eyes by stimulating the trigeminal nerve. These odors can have various negative effects on both quality of life and public health. The study investigated the physicochemical properties of oil composites enriched with natural additives and determined their effectiveness in reducing the intensity of nuisance odours. The research showed over 82% reduction in decaying meat odour and almost 65% reduction in ammonia odour. A higher impact of the given composites on reducing the odour from decaying meat than from ammonia was observed. This may be due to the biocidal properties of the additives used (turmeric, thymol, salicylic acid, hops and curly sorrel) and the higher intensity of ammonia odor compared to meat-derived odour. Despite the non-porous nature of the solids tested (with similar specific surface areas ranging from 0.66 to 0.88 m 2 /g), they were capable of sorbing NH 3 ., (© 2024. The Author(s).)

Waste cooking oil poses a serious threat to human health and the environment, both in households and in larger communities. One of the applications of waste cooking oil is composite materials called vegeblocks, which can be used for construction purposes. These composites are formed by the process of polymerisation, esterification and polyesterification. The resulting materials exhibit mechanical strength in line with the requirements for paving blocks. Composite materials that have been annealed for a minimum of 20 h at 200 °C or higher have the highest tensile strength (above 5 MPa). In contrast, composites with the highest flexural strength were obtained after processing at 210 °C for 16 h. The Saxa 2 variety showed the greatest inhibition of storage root growth (almost 43% compared to the control sample), as well as stimulation of root and leaf blade growth (by a maximum of 61.5% and 53.5%, respectively, compared to the control sample). The composite obtained from the maximum process parameters resulted in significant growth of both the root and the green part of both radish varieties by up to 35%. The study showed that the presence of vegeblocks in the plants causes stress conditions, resulting in increased peroxidase content compared to the control sample. The presence of the oil composite in the soil did not increase the amount of catalase in the radish, and even a reduction was observed compared to the control sample.

One method of managing used car tires is decomposition by thermochemical conversion methods. By conducting the process at temperatures of 450-750 °C, three fractions are obtained from tires: oil, gas, and solid. The liquid product of the pyrolysis of used car tires is pyrolysis oil, which consists of aromatic, polyaromatic, and aliphatic hydrocarbons. Unconventional building materials were obtained from tire pyrolysis oil and the environmental impact was evaluated. Blocks made from pyrolysis oil showed mechanical strength of up to about 1700 N. No heavy metals or polycyclic aromatic hydrocarbons, which were found in the crude heavy-PO fraction, were detected in the filtrates after incubation of the block obtained from the heavy-PO fraction at 240 °C. The highest inhibition of Sorghum saccharatum shoot (74.4%) and root (57.5%) growth was observed for solid materials from the medium-PO fraction obtained at 240 °C. The most favorable values of the parameters for the process of obtaining blocks based on post-PO were an annealing temperature of 180 °C, time of 20 h, and mass ratio of catalyst to catalyzed oil of 0.045.

In the second half of the 20th century, asbestos extraction was up to 4 Mt/year. Due to its high strength and insulation properties, this mineral was used as an additive in building materials. Over time these materials were destroyed by the process of weathering and leaching. Asbestos fibers in dust form penetrate the respiratory system causing diseases. This article proposes the binding of hazardous asbestos fibers in a polymer matrix formed from waste cooking oil. Compact materials were produced by heating catalyzed waste cooking oil and asbestos waste, and the process of obtaining these materials was optimized and their physicochemical and strength properties were determined. Oil-asbestos blocks contained sulfuric acid in a mass ratio of 0.05-0.30, being the mass of waste cooking oil, invariable mass of filling and 20% of waste cooking oil to the mass of the whole mixture. The materials were characterized by a compact structure and high hardness. The best mechanical strength above 140 N/mm was obtained for blocks with low acid to oil mass ratio ranging from 0.05 to 0.1125., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)