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The purpose of this paper is to investigate the efficacy of bacterial exopolysaccharides (Eps) in reactive black 5 (RB5) textile dye wastewater bioremediation.

The Eps were produced by bacteria isolated from cotton gin trash soils collected from different cotton-growing regions in Kenya for comparison purposes. A broth medium reconstituted using molasses was assessed for its capacity to produce the Eps. RB5 textile dye wastewater was optimized for dye removal under different temperatures, times and molasses concentrations. Dye removal was studied by Lovibond-Day Light Comparator, UV–Vis spectrophotometer and FTIR.

It was found that cotton gin trash soils contained Eps-producing bacteria. Three of the Eps studied were found to have the capacity to remove at least 80% of the dye from the wastewater.

This research did not assess the efficacy of the RB5 dye removal from the wastewater by mixtures of the Eps.

Bioremediation of textile dye wastewater with Eps produced by bacteria cultured from cotton gin trash soil is significant because it will offer an effective and cleaner alternative to the chemical coagulants.

Alternative treatment of textile wastewater with the Eps would result in safer water being released into the water bodies as opposed to the chemically treated wastewater that contains remnant chemicals.

Research on the use of Eps produced by bacteria isolated from cotton gin trash soils for removal of RB5 dye from textile wastewater has not been done before.

This paper aims to find a suitable solution to degrade the C.I. Reactive Red 24 (RR24) dyeing wastewater by using sodium persulphate to recycle water and inorganic salts.

The effects of temperature, the concentration of inorganic salts and Na₂CO₃ and the initial pH value on the degradation of RR24 were studied. Furthermore, the relationship between free radicals and RR24 degradation effect was investigated. Microscopic routes and mechanisms of dye degradation were further confirmed by testing the degradation karyoplasmic ratio of the product. The feasibility of the one-bath cyclic dyeing in the recycled dyeing wastewater was confirmed through the properties of dye utilization and color parameters.

The appropriate conditions were 0.3 g/L of sodium persulphate and treatment at 95°C for 30 min, which resulted in a decolorization rate of 98.4% for the dyeing wastewater. Acidic conditions are conducive to rapid degradation of dyes, while ·OH or SO₄⁻· have a destructive effect on dyes under alkaline conditions. In the early stage of degradation, ·OH played a major role in the degradation of dyes. For sustainable cyclic dyeing of RR24, inorganic salts were reused in this dyeing process and dye uptake increased with the times of cycles. After the fixation, some Na₂CO₃ may be converted to other salts, thereby increasing the dye uptake in subsequent cyclic staining. However, it has little impact on the dye exhaustion rate and color parameters of dyed fabrics.

The recommended technology not only reduces the quantity of dyeing wastewater but also enables the recycling of inorganic salts and water, which meets the requirements of sustainable development and clean production.

Cesspits are the means for each house to dispose of wastewater in the Bani Kinanah District (BKD) of Jordan, which creates severe environmental complications. This research aimed to find a suitable site for a wastewater treatment plant (WWTP) in BKD.

Geographic Information System (GIS)-based multicriteria decision analysis (MCDA) was used for an optimal site selection for a sewage treatment plant. Several datasets were obtained to prepare the maps of the criteria influencing the choice of the most suitable site for the WWTP. The analytic hierarchy process was used to apply the weights for each factor.

Five classes of suitability were generated: 0.23% very high suitability, 8.49% high suitability, 47.12% moderate suitability, 37.67% low suitability and 6.49% very low suitability. According to Analytical Hierarchy Process (AHP) results, the elevations, slope and groundwater depth have high importance; where their weights 21%, 19% and 17%, respectively. The most suitable site for establishing a WWTP was found in the northern part of the study area, where it is characterized by relatively low elevations (−90 to −93 m), low slope (0–2.5 %), distance from groundwater level (47–82 m) and the space is sufficient for building the plant (25328 m², 8861 m² and 8586 m²).

This research is limited by the availability of data.

The research is invaluable for decision makers involved in urban planning.

Wastewater treatment plants are essential for communities with limited resources such as Jordan. It has also profound impacts on the surrounding environment.

From the present study, it can be concluded that GIS is essential in urban utility establishment, like urban domestic wastewater treatment site selection. Although the study area has adequate potential areas for establishing WWTP, further assessment of flood vulnerability, wastewater amount quantification, population growth and urban expansion must be seriously considered before implementation.

In addition to agriculture, energy production, and industries, potable water plays a significant role in many fields, further increasing the demand for potable water. Purification and desalination play a major role in meeting the need for clean drinking water. Clean water is necessary in different areas, such as agriculture, industry, food industries, energy generation and in everyday chores.

The authors have used the different search engines like Google Scholar, Web of Science, Scopus and PubMed to find the relevant articles and prepared this mini review.

The various stages of water purification include coagulation and flocculation, coagulation, sedimentation and disinfection, which have been discussed in this mini review. Using nanotechnology in wastewater purification plants can minimize the cost of wastewater treatment plants by combining several conventional procedures into a single package.

In society, we need to avail clean water to meet our everyday, industrial and agricultural needs. Purification of grey water can meet the clean water scarcity and make the environment sustainable.

This mini review will encourage the researchers to find out ways in water remediation to meet the need of pure water in our planet and maintain sustainability.

The novelty addressed here is undertaken by using tailor-made and fully characterized starch nanoparticles (SNPs) having a particle size ranging from 80 to 100 nm with a larger surface area, biodegradability and high reactivity as a starting substrate for cadmium ions and basic dye removal from wastewater effluent. This was done via carboxylation of SNPs with citric acid via esterification reaction using the dry preparation technique, in which a simple, energy-safe and sustainable process concerning a small amount of water, energy and toxic chemicals was used. The obtained adsorbent is designated as cross-linked esterified starch nanoparticles (CESNPs).

The batch technique was used to determine the CESNPs adsorption capacity, whereas atomic adsorption spectrometry was used to determine the residual cadmium ions concentration in the filtrate before and after adsorption. Different factors affecting adsorption were examined concerning pH, contact time, adsorbent dose and degree of carboxylation. Besides, to validate the esterification reaction and existence of carboxylic groups in the adsorbent, CESNPs were characterized metrologically via analytical tools for carboxyl content estimation and instrumental tools using Fourier-transform infrared spectroscopy (FTIR) spectra and scanning electron microscopy (SEM) morphological analysis.

The overall adsorption potential of CESNPs was found to be 136 mg/g when a 0.1 g adsorbent dose having 190.8 meq/100 g sample carboxyl content at pH 5 for 60 min contact time was used. Besides, increasing the degree of carboxylation of the CESNPs expressed as carboxyl content would lead to the higher adsorption capacity of cadmium ions. FTIR spectroscopy analysis elucidates the esterification reaction with the appearance of a new intense peak C=O ester at 1,700 cm⁻¹, whereas SEM observations reveal some atomic/molecules disorder after esterification.

The innovation addressed here is undertaken by studying the consequence of altering the extent of carboxylation reaction expressed as carboxyl contents on the prepared CESNPs via a simple dry technique with a small amount of water, energy and toxic chemicals that were used as a sustainable bio nano polymer for cadmium ions and basic dye removal from wastewater effluent in comparison with other counterparts published in the literature.

The purpose is to conduct a systematic review of circular water management and its role in improving water availability amid increased demand and decreased supply.

A systematic literature review was implemented, which helped in the identification, selection and critical appraisal of the various research to answer the research question. It was guided by the Preferred Reporting Items for Systematic Reviews (PRISMA) statement. The review was conducted mainly on Web of Science and Scopus databases between November 20 and December 8, 2022, with search strategies involving free-text searching, phrase searching, truncation and Boolean operators.

The search process yielded 46 articles exploring circular water management. The findings reveal that circular water management offers more promise than linear or business-as-usual approaches. There are various circular water management models, although most of them emphasize a shift from the “take, make, consume and waste” principles. Contrarily, the success of the circular water management framework hinges on its ability to embrace resilience based on changing environmental conditions. Furthermore, the model focuses on improving inclusiveness with various stakeholders working together to improve water management.

The research is the first of its kind as it identifies a critical gap, the imperative need to develop a universal framework that can significantly advance the comprehension of circular water management.

The host–guest molecules are often used in various fields and applications. This paper aims to discuss the role of host–guest complexes in the textile industry, focusing on calixarenes as a potential adsorbent for hazardous dyes. The paper begins with an introduction to nanotechnology and its many uses, including textiles.

The risks associated with the utilisation of dyes and its adverse effects on the environment are then also highlighted. This paper also discusses the structure and characteristics of calixarenes and their potential use as an adsorbent to extract toxic metals from aqueous solutions. The paper also explains the molecular structure of calixarenes, especially the ability of its upper and lower rims, which can be altered to yield derivatives with various selectivities for diverse guest ions and small molecules. In addition, the application of various host–guest molecules in the textiles industry to extract dyes also had been discussed.

In conclusion, the paper highlights the essential in establishing a systematic review on the significance of selective adsorbents, such as calixarenes, to isolate particular targets from diverse matrices in the textile industry.

Only discussing several applications for several host–guest molecules.

The paper concisely describes various host–guest molecule applications in the textile industry, with each molecule being elaborated upon in detail.

This article examines the dairy value chain in Southern Peru and identifies four critical success factors that can enhance the local situation.

The study employed descriptive research using semi-structured interviews with entrepreneurs from 17 cheese factories across eight districts, namely Azángaro, Ayaviri, Pucara, Lampa, Cabana, Acora, Pomata and Puno. Quantitative market data were also gathered and analyzed alongside qualitative views.

The study identified four critical issues: quality concerns in milk production, suboptimal managerial practices of cheese-processing plants, lack of compliance to regulations, particularly hygiene and environmental ones, and inadequate access to finance. The findings reveal a gap between the practices of the Puno region's dairy industry and world-class standards for cheese production. Urgent actions are required to improve product quality, increase access to finance, enhance managerial education and ensure compliance with regulations.

Results suggest critical issues to be prioritized, but the article does not propose how to solve the problems identified. External factors, such as economic changes, were also not considered. Interviews were conducted exclusively with cheese processing entrepreneurs, not milk producers.

This case study provides an insight into the interior of Peru, an under-researched region facing several development challenges. The findings have significant implications for dairy value chain stakeholders in Peru and other similar contexts.

Herein, this study aims to use our recently tailored and fully characterized poly acrylonitrile (AN)-starch nanoparticle graft copolymer having 60.1 graft yield percentage as a starting substrate for copper ions removal from wastewater effluent after chemical modification with hydroxyl amine via oximation reaction as a calorimetric sensor.

The calorimetric sensor batch technique was used to determine the resin's adsorption capacity, while atomic adsorption spectrometry was used to determine the residual copper ions concentration in the filtrate before and after adsorption. This was done to convert the copolymer's abundant nitrile groups into amidoxime groups, and the resulting poly (amidoxime) resin was used as a copper ion adsorbent. To validate the existence of amidoxime groups, the resin was qualitatively characterized using a rapid vanadium ion test and instrumentally using Fourier transform infrared spectroscopy spectra and scanning electron microscopy morphological analysis.

At pH 7, 400 ppm copper ions concentration and 0.25 g adsorbent at room temperature, the overall adsorption potential of poly (amidoxime) resin was found to be 115.2 mg/g. The process's adsorption, kinetics and isothermal analysis were examined using various variables such as pH, contact time, copper ion concentration and adsorbent dose. To pretend the adsorption kinetics, various kinetics models, including pseudo-first-order and pseudo-second-order, were applied to the experimental results. The kinetic analysis indicated that the pseudo-second-order rate equation promoted the development of the chemisorption phase better than the pseudo-first-order rate equation. In the case of isothermal investigations, a study of observed correlation coefficient (R²) values indicated that the Langmuir model outperformed the Freundlich model in terms of matching experimental data.

To the best of the author's information, there is no comprehensive study for copper ions removal from waste water effluent using the recently tailored and fully characterized poly (AN)-starch nanoparticle graft copolymer having 60.1 graft yield percentage as a starting substrate after chemical modification with hydroxyl amine via oximation reaction as a calorimetric sensor.

The purpose of this study is to ascertain how cluster organisations have been fostering green transformation in Poland.

This paper adopts a multiple case study approach. Data collection methods involved in-depth interviews with cluster organisation managers and researchers to identify support measures for green transformation and to investigate the factors influencing their actions as well as a comprehensive analysis of documents, including cluster organisations‘ strategies.

Cluster organisations manage and participate in actions that create favourable conditions for pursuing low-carbon and circular economy ventures. They not only assist their members in overcoming obstacles related to green transformation but also engage non-members – which can lead to spillovers reaching beyond their borders. Their engagement takes place across all phases of the green transformation process.

For various reasons, the research was designed as qualitative to understand the opinions and experiences of various actors engaged in green transformation within cluster organisations’ ecosystems. The key factor influencing this decision stems from the fact that knowledge of the involvement of cluster organisations in supporting green transformation still needs to be completed and scattered. The limitations of the study include limited access to information and the fact that qualitative research allows for a certain amount of subjectivity, and the results should be generalised carefully. Moreover, the interviews were carried out with a non-random sample of participants. Another limitation of the study is related to biased views, which could have been shared by interviewees acting as representatives of the studied cluster organisations.

Cluster organisations have emerged as drivers of circular transition by promoting sustainable practices such as material recycling, biological recovery and parts harvesting. These initiatives contribute to reducing waste, conserving resources, and minimising the environmental footprint of industries. These organisations can be active agents of transformation, orchestrating collaborative efforts that have a far-reaching impact on industries and economies.

This is one of the first and most comprehensive studies on the role of cluster organisations in Poland in supporting green transformation. This paper identifies and systematises the actions undertaken to provide a clear understanding of the internal processes within cluster organisations.