In this study, the use of interior dyes with antibacterial properties was examined. Boric acid (H3BO3), which is a cheap and easily obtainable boron compound from our country's resources, has an antibacterial effect. Within the scope of the study, firstly, boric acid mixtures were prepared in appropriate concentrations and antibacterial dye production studies were carried out by adding them to indoor dyes. The antibacterial properties of the obtained dye were investigated through the inhibition effect on E. coli bacteria and its antibacterial activity was tested, and then the brightness, density, film thickness, scorching, pencil hardness and drying time tests of the dyes and the suitability of their characteristics to TS 5808/2012 and the applicability of these dyes were evaluated. The results showed that the antibacterial effect of boric acid did not have a negative effect on the dye quality, but maintained the standard values of the dye.

The aim of this study is to investigate new catalytic systems for the degradation of a dye that has been classified as first-degree toxic pollutant. Advanced oxidation process such as photocatalytic oxidation, ultrasonic oxidation, Fenton, and Fenton-like constitute a promising technology for the treatment of wastewater containing organic compounds. Waste effluents from textile industries are a major source of water pollution. These wastewaters contain dyes, which have high toxicity and low biodegradability. In this study, degradation of Nile Blue (NB), an azo dye, was studied using the photocatalytic oxidation (TiO2 and silver-loaded TiO2 (Ag-TiO2) as catalyst), ultrasonic oxidation, Fenton (Fe(II)/H2O2), and Fenton-like (Cu(II)/H2O2, V(IV)/H2O2) processes. It was found that the photocatalytic degradation of NB increased with decreasing pH, and the degradation rate also increased in the presence of TiO2/UV compared to UV irradiation alone. In addition, Ag loading on TiO2 dramatically reduced the degradation time. The ultrasonic degradation of NB was also studied using different initial dye concentrations at different pH values and amplitudes. Concentrations of Fe(II), Cu(II), V(IV) and H2O2 on degradation ratio were investigated. It is found that Fe(II) ion is more effective than Cu(II) and V(IV) ions in the degradation of NB.

This study investigates the optimisation of hydrothermal carbonisation (HTC) parameters for transforming Whitewood biomass into hydrochar, focusing on bioenergy production and valuable chemical extraction as by-products. The optimal carbonisation was achieved at a process temperature of 240 -260 °C, which optimised the higher heating value of the hydrochar to 27-30 kJ/g and ensured a structural integrity similar to lignite coal. Increasing the temperature beyond 260 °C did not significantly enhance the energy content or quality of the hydrochar, establishing 260 °C as the practical upper limit for the HTC process. Residence times between 30 to 60 min were found to have minimal impact on the yield and quality of hydrochar, suggesting significant operational flexibility and the potential to double throughput without increasing energy consumption. The study also revealed that the process water by-product is rich in furan compounds, particularly furfural and hydroxymethyl furfural, with their highest concentration (125 mg/g of feedstock) occurring at 220 °C. The implementation of these findings could facilitate the development of a large-scale HTC facility, significantly reducing reliance on fossil fuels and enhancing economic viability by producing high-energy-density biofuels and high-value chemical by-products.

In this study, chitosan-bentonite beads were prepared by using bentonite and chitosan as fertilizer carrier materials and urea as fertilizer components. The prepared samples were named BUC0.2, BUC0.4 and BUC0.6 based on the bentonite ratios of 0.2%, 0.4% and 0.6% (weight/volume). In the FT-IR and XRD results, it was seen that the characteristic peaks of the bentonite structure became evident in the BUC0.6 sample, while chitosan peaks were dominant in the BUC0.2 sample, as expected. As the amount of bentonite increased, the swelling ratio generally increased from 31.6% to 48.6. In the nitrogen release experiments, a very rapid nitrogen release occurred in the first hours of release. It was thought to be due to the rapid dissolution of urea in water. The cumulative release percentage showed a slightly decreasing trend in the days following the release experiment. When nitrogen release profiles of the samples containing different amounts of bentonite were compared, it was observed that the nitrogen release curves were quite close to each other due to the lower bentonite ratio. Release percentages of the samples containing different amounts of bentonite were obtained between 61.2-67.7. Observations supported the efficient degradation of fertilizers in the soil environment. As a result, it was evaluated that the prepared materials were promising as environmentally friendly nitrogen fertilizer.

Caprolactam is most commonly used in the production of Nylon 6 in industry and is generally produced from cyclohexanone by the Beckmann rearrangement. Orthophosphoric acid is generally used in fertilizer production and is produced through two processes: wet and dry. In this study, detailed characterization of CL-PA was carried out by synthesizing CL-PA ionic liquid from orthophosphoric acid (PA) and caprolactam (CL). FTIR, Raman and UV-Vis spectroscopic analyses reveal that a bond is formed between CL and PA. The thermal behavior of CL-PA ionic liquid was inspected by TGA and DSC. It has been observed that the decomposition temperature of CL-PA ionic liquid is different from that of the starting materials (CL and PA). It was disclosed by DSC analysis that CL-PA ionic liquid only has a glass transition temperature. The room-temperature CL-PA ionic liquid synthesized from solid CL with melting point of 70.34 ℃ and 85 wt.% PA did not show any melting or freezing point and the glass transition temperature was found to be −27 ℃. It was revealed that CL-PA ionic liquid was more thermally stable than CL which alone almost completely evaporated at about 197 ℃. As a result of FTIR analysis of CL-PA ionic liquid and its constituents, it was demonstrated that –NH peaks of CL disappeared in the CL-PA spectrum and the peak of C=O group shifted to a lower frequency (i.e., 1604 cm⁻1). In the Raman analysis of CL-PA and its constituents, it was observed that the asymmetric C=O bending vibration and C=O stretching vibration of CL disappeared in the CL-PA spectrum. In the UV spectrum, it was observed that the maximum absorbance of CL-PA ionic liquid varied with respect to that of CL.

The increasing presence of presistent synthetic dyes, like crystal violet (CV), in wastewater poses a significant threat to aquatic ecosystems and human health due to its genotoxicity and carcinogenicity. Biochar derived from agricultural waste offers a promising, cost-effective, and eco-friendly approach for dye removal. This study explores the potential of flamboyant pod biochar (FPB) as a novel and sustainable adsorbent for CV removal. FPB offers a unique advantage as it utilizes readily available flamboyant pod waste, promoting waste valorization and a cost-effective approach. FPB was synthesized through a simple process involving milling, sun-drying, and pyrolyzing flamboyant pod waste at 300 °C. Batch adsorption experiments were conducted to evaluate the influence of contact time and initial dye concentration on removal efficiency. Kinetic modeling using pseudo-first-order and pseudo-second-order models explored the underlying mechanisms governing the adsorption process. The pseudo-second-order kinetic model exhibited a superior fit (R² > 0.87) compared to the pseudo-first-order model, suggesting a chemisorption mechanism governing the adsorption process. These findings demonstrate the potential of FPB as a low-cost, sustainable adsorbent for CV removal from wastewater.

This study investigates the extraction of natural colorant from fresh fruits of Parthenocissus quinquefolia L. and the application of the extracted dye to wool yarn, cotton, and polyester fabrics in the presence and absence of various mordants. The effect of mordant type on the dyeing quality with different mordanting methods was examined. Iron sulfate, tin chloride, alum, copper sulfate, and potassium dichromate were used as mordant. The effects of these mordants on the color of the dyed samples were investigated in terms of CIELab (L*, a*, b*) and K/S values. The light, washing and rubbing fastness of the dyed samples were evaluated according to ISO standards. While dyeing wool yarn without mordant produces reddish brown, and dyeing with mordant produces a wide range of colors from green to purple, blue and lilac tones are obtained in cotton fabric dyeing, and green, purple and brown tones are obtained in polyester fabric dyeing. While polyester fabrics are dyed with synthetic dyes at 130 oC, in this study they were dyed with natural dyes at 90 oC. As a result of dyeing, colors with high fastness are generally obtained.

32CrMoV12-10 steel is widely utilized in industries where high strength and toughness are crucial. This alloy is commonly used in manufacturing components like gun barrels, gears, and bearings, which demand exceptional mechanical properties. These parts typically undergo heat treatments, including hardening and surface enhancement techniques such as nitriding, to extend their fatigue life significantly. It is crucial to identify optimal heat treatment conditions to achieve desired material performance. In this study, commercial 32CrMoV12-10 steel was selected to investigate the impact of heat treatment parameters (temperature, duration time, and quenching media) on its mechanical properties. To analyse the effect of these parameters, the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) and the Taguchi Method were employed, facilitating a systematic examination of the process stages and subsequent mechanical testing outcomes, including Charpy V-notch impact, hardness, and tensile strength assessments. An optimal heat treatment protocol was established based on these analyses, and the nitriding depth of the optimally treated sample was examined using a micro-Vickers hardness tester. For comparative analysis, another sample with closely related outcomes was also evaluated. Results indicated that the surface hardness of the optimally treated Sample 10 reached 870 HV, with a core hardness of 417 HV, compared to non-nitrided Sample 3, which showed a surface hardness of 860 HV and a core hardness of 415 HV. Despite the proximity in their values, Sample 10 exhibited slightly higher micro-Vickers hardness than Sample 3. However, while Sample 3 fails to meet the specified tensile stress and hardness criteria, Sample 10, produced through optimization, meets criteria, ranging from 970 to 1040 N/mm², underscoring the efficacy of the optimization process facilitated by TOPSIS. This optimization was notable for its minimal experimental requirements, proving effective in conserving time, energy, and resources while investigating the processed material.

In this work, the P1-approximation of the radiative transfer equation (RTE) was used for the description and optimization of the radiant field in a flat plate photoreactor under solar radiation with three commercial brands of titanium dioxide photocatalysts. The boundary layer of photon absorption (δ_abs), the average volumetric rate of photon absorption (VRPA), and a new apparent optical thickness (ζ_app1) were used as design parameters for optimization. A simple mathematical expression for the calculation of δ_abs also called the best reactor thickness was formulated. For the three catalysts, varying the reactor height (L), it was found a decrease in the local volumetric rate of photon absorption (LVRPA) from the top side until the bottom of the reactor for any value of the catalyst loading (Ccat). It was also observed that when Ccat increases the VRPA increases exponentially until a fixed value where it remains almost constant. With L= 1 cm, the optimum Ccat (Ccatop) was 0.2 g/l in 0.85 cm of thickness, 0.3 g/l in 0.82 cm of thickness, and 0.4 g/l in 0.89 cm of thickness for the photocatalysts Degussa P-25, Aldrich, and Hombitak respectively. The optimum apparent optical thickness (ζ_(app1,op)) was 4.03, 4.62, and 3.7 for the photocatalysts Degussa P-25, Aldrich, and Hombitak respectively. These results are in good agreement with the literature. Results found in this work give predictions on radiation absorption in flat plate photocatalytic reactors with different heights.

The packaging industry as a pioneer in waste production is looking for environmentally friendly and green solutions in these days. These factors are driving the development of packaging and forcing the industry to invest in research and development to make flexible packaging more sustainable than the existing packaging options. In this review, the factors of main ingredient’s selection on migration barrier properties have been investigated within the new designed heat-sealing lacquer. The new heat-sealing lacquer design has been carried out, which will ensure thermal sealing in Aluminum/Pet Blister Packaging structure, suitable for direct contact food, and at the same time prevent the migration of printed ink to the secondary packaging layer, Pet film side. Because of laboratory tests, the effects and results of heat-sealing lacquer formulations have been assessed and prevented the negative ink migration tendencies in existing heat-seal lacquers for blister packaging structure. That would be possible to use the obtained PET film by recycling processes as a green solution to flexible packaging sector. In this way, Pet films can be separated and used in recycling processes when blister packaging printed with new designed heat-sealing lacquer