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The use of solid wastes as an adsorbent for dye removal from wastewater is one of the leading steps of sustainable waste management. In this research, the removal of Methylene Blue dye by cuttlefish bone waste was examined by using peppermint extract. Zn-doped cuttlefish bone was prepared by the green synthesis method in laboratory conditions for the comparison of cuttlefish bone in adsorption and ultrasonically-assisted adsorption processes. The results of this study exhibited that Methylene Blue removal with Zn-doped cuttlefish bone was higher than that with cuttlefish bone at all pH values. The qmax values obtained from the Langmuir isotherm model were calculated as 8.96 mg/g and 12.74 mg/g in the adsorption process with cuttlefish bone and Zn-doped cuttlefish bone, respectively. The qmax value relatively improved to 18.05 mg/g in the ultrasonically-assisted adsorption with Zn-doped cuttlefish bone. With the green synthesis, the qmax increased by 1.42 times, while this increase was 2.01 times with the application of the ultrasonically-assisted adsorption process using Zn-doped cuttlefish bone compared to the adsorption process using cuttlefish bone. [ABSTRACT FROM AUTHOR]

Today, adsorption has become the focus of attention for the uptake of heavy metal ions, industrial dyes and pharmaceuticals. This focus is due to the regeneration of the adsorbent and the minimization of the chemical through the adsorption technique, resulting in high efficiency of adsorption and the possibility of metal recovery, flexibility and simplicity of design. In recent years, the number of studies using chemically modified textile waste as adsorbents has increased due to their high adsorption capacity and regeneration ability, thus achieving high efficiency. On the other hand, the increasing world population inevitably leads to an increase in the amount of waste left from the textile industry, together with the increase in demand for textile and ready-made clothing products. While these textile waste cause disposal problems within the framework of waste management, they also reveal the need for solutions that support sustainable development. Recently, many studies have been conducted on the preparation of activated carbons from various materials. For example, the fact that cotton textile waste is considered a good carbon source because it is rich in cellulose and other substances draws the attention of researchers in this direction. Therefore, this study aims to discuss the technological developments in this context and to reveal the deficiencies or weaknesses of these developments by examining the studies investigating the potential of textile waste in the removal of contaminants such as dyes, metals and pharmaceuticals. [ABSTRACT FROM AUTHOR]

The galvanising industry's wastewater treatment facilities generate waste metal hydroxide. These sludges have the potential to be used to remove textile dyes from effluents. In this study, three reactive dyes, which are frequently used in cellulosic textile materials' dyeing, Remazol Turquoise Blue G 133% (CI RB21), Remazol Red 3B (CI RR23), and Remazol Red 3BS 133% (CI RR239) were used to investigate the color removal efficiency of aluminum hydroxide sludge (AHS) depending on dye chromophore. Adsorption studies were conducted under varying conditions of pH, initial dye concentrations, and AHS doses. The characteristics of the AHS were examined by SEM (EDX and DX-Mapping), BET, XRD, and FTIR. The maximum dye removal was achieved at pH 3 for CI RB21, and at pH 5 for CI RR239 and CI RR23. Over 90% of dye removal was obtained for CI RR239 and CI RB21, when the adsorbent dosages were 8 g/l and 5 g/l, respectively. For CI RR23, the highest color removal percentage was only 72.7%, when the dosage of adsorbent was 10 g/l. It was also determined that at 500 mg/l initial CI RB21 dye concentration, the removal percentage of CI RB21 reached 95%, while the maximum removal percentages (95% for CI RR239 and 68.3% for CI RR23) were achieved at the 200 mg/l and 100 mg/l initial dye concentrations for CI RR239 and CI RR23, respectively. In the study, it was observed that the number of sulfo groups affecting the ionic charge of dye molecules and molecular weights of the dyes have a significant effect on the dye removal efficiency. Metal hydroxide is produced from treating wastewater from galvanising industry. Aluminium hydroxide sludge is cheap and efficient to remove dyes from textile wastewaters. Number of sulfo groups and molecular weights of dyes are significant for color removal efficiency. The highest dye removal by aluminium hydroxide sludge occurs in acidic conditions and dyes having higher molecular weight and higher number of sulfo groups. [ABSTRACT FROM AUTHOR]

Agro-wastes are recognised as a carbon-rich source, which can be converted into value-added products in sustainable development. In this study, the effect of pH, contact time, initial concentration, and ionic strength were evaluated in Methylene Blue (MB) adsorption by using an activated carbon obtained from pyrolysed almond (PAS) and walnut shells (PWS). The characterisation of PAS and PWS was conducted by SEM-EDX, FT-IR and BET analysis. The removal efficiency of 6 mg/L initial MB concentration improved from 10.6% to 50.42% for PAS, when the adsorbent dose was increased from 0.5 g to 3.5 g/L in 1 L dye solution. It also improved from 14.8% to 48.7% for PWS, when the adsorbent dose was increased from 0.5 g to 3.5 g. The adsorption fits well with the Freundlich isotherm model and the second-order kinetic model is more favourable. In the adsorption experiments using PWS, 48% removal efficiency was obtained in the absence of NaCl. Depending on the increasing NaCl concentration, the removal efficiencies showed a decrease. 36% removal efficiency was obtained for PWS when 2500 mg/L NaCl was used. In the adsorption experiments using PAS, 40% removal efficiency was obtained in the absence of NaCl. When 500 mg/L NaCl was used, the maximum removal efficiency improved to 48%. However, with the increase in ionic strength, removal efficiencies decreased to approximately 39%. This study revealed that PAS and PWS could be used effectively instead of commercial activated carbon, which also provides an advantageous option from an economic point of view. [ABSTRACT FROM AUTHOR]

In sustainable waste management, reusing coffee waste such as husks or spent coffee grounds helps convert a huge amount of waste into a new resource. In this study, H3PO4-activated filter coffee waste (H3PO4-FCW) and ZnCl2-activated filter coffee waste (ZnCl2-FCW) were synthesised, and the characterisation of them was revealed by SEM, EDAX, FTIR and XRD analyses. Adsorption isotherms (Langmuir, Freundlich, Temkin and Dubinin–Radushkevich), adsorption kinetics (Elovich, pseudo-second-order kinetics, pseudo-first-order kinetics including error functions) and adsorption thermodynamics were determined and the effect of parameters such as pH, adsorbent dose, initial methylene blue (MB) concentration, adsorption time and temperature on MB removal was evaluated by the ultrasonic-assisted adsorption. It was observed that ultrasonic-assisted adsorption was more suitable for the Langmuir isotherm for both adsorbents and that the adsorption kinetics was better suited to the pseudo-second-order kinetics. In addition, the ultrasonic-assisted adsorption using H3PO4-FCW and ZnCl2-FCW occurred endothermically and the adsorption mechanism was physisorption. MB removal with ZnCl2-FCW could reach over 90% when pH is between 3 and 7 in the ultrasonic-assisted adsorption process. The maximum adsorption capacity was obtained as 42.7 mg/g and 106.4 mg/g for H3PO4-FCW and ZnCl2-FCW, respectively. It was seen that the qmax value of ZnCl2-FCW was 2.5 times higher than the qmax of H3PO4-FCW. Moreover, reusability studies showed that MB removal of over 90% could be achieved in the 2nd use of H3PO4-FCW and ZnCl2-FCW. In conclusion, high dye removal could be achieved by synthesising low-cost adsorbents. The use of filtered coffee wastes in the adsorption of basic dyes such as MB is, therefore, important in terms of both waste reduction and management. [ABSTRACT FROM AUTHOR]

Microplastics, especially microfibres, have been identified in aquatic sources worldwide. This study aims to determine the amount of microfibres discharged into wastewater from the washing of textile products domestically in the province of Tekirdag, Thrace Region of Turkey. Experimental studies were conducted to measure the release of these microfibres from the domestic laundry of fabrics with different fibre compositions. The wastewater collected from the washing machine outlet was passed through filters of different sizes, such as 200 µm, 100 µm, 50 µm and 5 µm. A simulation model was built to evaluate the accumulation of these microfibres between 2017 and 2030 by taking into account regional population dynamics and social behaviour patterns in the province. The literature review and questionnaire study constituted data for the model. As a result of this study, it was determined that the 200 µm (62.3%) and 5 µm (19%) filters show the highest uptake rate respectively and the weight of microfibres held in the 200 µm filter varies between 52.59% and 70.94%. It was estimated that the microfibre release resulting from the annual laundry activity in Tekirdag could reach approximately 55.9 tonnes (35.6 tonnes for >200 µm, 5 tonnes for 100-200 µm, 5.2 tonnes for 50-100 µm and 10.1 tonnes for 5-50 µm). The sensitivity analysis of the model simulation also showed that the accumulation of microfibres in Tekirdag is estimated to range between 30 and 200 tonnes for the project period. It was determined that if 200 µm filters are used in machines, approximately 53% of microfibre accumulation can be prevented without passing into the aquatic ecosystem, compared to using 5 µm filters. [ABSTRACT FROM AUTHOR]

This study examines the dynamic change in population and municipal waste generation during the COVID-19 pandemic. A stockflow infection modelling was used to link population dynamics with disease transmission parameters (such as probability to catch COVID-19 and population interactions) to estimate municipal waste generation in the province of Tekirdag, Turkey. Three different scenarios (Scenario 1: severe conditions with possible mutation of coronavirus, Scenario 2: moderate conditions with the continuation of the current case and Scenario 3: mild conditions with intensified vaccination) were produced and simulation results were analysed. The results show that it is expected to have a peak with 230 000 people with severe symptoms in Scenario 1. It is also expected to have 1 person/week to pass away due to inadequate health infrastructure if the annual healthcare capacity improvement rate in the province remains at its current rate (1%). The results indicate that the amount of dry recyclables increases over time in the three scenarios. However, in Scenario 3, a total of 450 000 - 780 000 tonnes of dry recyclables are expected to be produced at the end of 3 years. This high amount of waste is likely to cause dynamism in the recycling activities of the province. As far as it is concerned that 750 000 - 1 000 000 tonnes of residual waste (including used masks) are expected to be produced in Scenario 3, capacity improvement for the only landfill site of the province should be made urgently or an alternative solid waste disposal facility should be put into use to meet this need. [ABSTRACT FROM AUTHOR]

In this study, the accumulation of microfilaments in aquatic systems due to domestic laundry activities in the Thrace Region of Turkey was investigated by adopting the dynamic system modelling approach. The parameters regarding the population of the region, prevalence of washing, filtration, wastewater treatment efficiency and microfilaments discharge were linked and the relationship between them was determined mathematically. Two different scenarios based on technological improvements in fabrics and behavioural laundry changes of the society were produced to examine the microfilament accumulation in the long term with Monte Carlo Sensitivity Analysis. In the 1st scenario, microfilament accumulation was examined when advanced techniques are used in treatment efficiency and filters are located in washing machines, while in the 2nd scenario, filament shedding during washing is limited with the improvements to be made in fabric technology and frequency of washing laundry is decreased by raising awareness of local people on environmental issues. As a result, microfilament accumulation from laundry activities is estimated to reach approximately 500 tonnes by the end of 2035 in the project region. In the 1st scenario, it was seen that the microfilament accumulation varies between 25 and 450 tonnes during the project period. This value changes between 30 and 150 tonnes in the 2nd scenario. The results show that initiatives to prevent pollution at its source (such as increasing fabric technology) are more effective in reducing particles accumulated in aquatic systems in the long run compared to pollution cleaning-up efforts. [ABSTRACT FROM AUTHOR]

It has been determined that a high percentage of medical waste could be classed as domestic waste due to the lack of segregation at hospitals. Better segregation could thus substantially decrease the amount of medical waste that is required to be treated as hazardous waste. This study aims to assess different segregation levels of domestic waste mixed with medical waste. To do so, the Stella and Vensim simulation packages were used to evaluate medical waste flows in the Thrace Region of Turkey. The most important advantage of the simulation modeling used in this study is the flexibility for adjusting parameters based on circumstances, e.g. in the case of an unforeseen event (such as the COVID-19 pandemic), the system parameters can be modified according to the situation. In this study, it is anticipated for the medical waste generation to increase from almost 2000 tons/year to 3000 tons/year in 2045 in the region, which is more than the capacity of current medical waste treatment plants. Projected waste generation flows show that it is possible to avoid 300 tons of medical waste annually by reducing the domestic content of medical waste to 50%. Precisely, for the current regional treatment capacity to be sufficient up to 2045, it will be crucial to reduce the domestic content in medical waste to 10% in the chronic care departments at regional hospitals. The importance of this further arises, as lack of meeting this need will result in an urgent requirement for installation of new units for the treatment of all the medical waste generated in the region. [ABSTRACT FROM AUTHOR]

An Erratum to this paper has been published: https://doi.org/10.3103/S1063455X22050125 [ABSTRACT FROM AUTHOR]