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Cationic resin is widely used in decolouring of textile wastewaters. Tonnes of resin are used in sector, and disposal of resin is being a second waste problem. The purpose of this paper is to investigate the adsorption behaviour of the methylene blue cationic dye from aqueous solution on the cation exchanger Lewatit CNP80 to understand the regenerability of cation exchanger resin from textile wastewaters.

Cationic resin was used as an alternative low-cost adsorbent for removing methylene blue dye from textile wastewaters. The adsorption study was carried out in the batch mode. Batch adsorption studies were carried out to examine the effect of parameters such as methylene blue concentration, temperature, pH, resin dose, shaking speed and contact time.

It was observed that dye-removal capacity of resin was reached from 17 mgg⁻¹ to 19.4 mgg⁻¹ at 25 °C temperature, pH 5 in 15 min. At the appropriate range of parameters, it was observed that more than 98% removal efficiency was achieved for methylene blue dye, and also, this study was focussed on whether the resin regenerates. In regeneration studies, our purpose was to recover of non-regenerable exhausted cationic resin by NaOCl. Regeneration of Lewatit CNP80 was performed in five cycles. After regeneration, the authors tried to determine whether the adsorption capacity was affected by regeneration.

In this study, the authors focussed on regeneration studies. The aim is to find easy, low-cost regeneration agent. In conclusion, the authors found that NaOCl is eligible for regeneration studies. The exhausted resin was recovered by NaOCl, and the authors also tested 5th regeneration cycles. Sodium hypochlorite is not a common regeneration agent for adsorption studies. Generally, resin is regenerated by HCl or other regeneration agent products. As a result of that, operational cost was reduced, and the other thing that the authors want to emphasise is textile industry wastewater based high temperature; therefore, this regeneration study can easily work with textile industries.

In this study, polyvinyl alcohol (PVA)/poly[acrylic acid (AAc)-co-acrylamide (AM)] composite hydrogel was prepared by radical copolymerization in the presence of Fe³⁺ freezing-thawing method. The swelling behavior of the hydrogel was investigated. The novel synthesized hydrogel was used as an adsorbent for the removal of dyes from aqueous solutions. In this paper, methylene blue and maxilon blue 5G were selected as representative cationic dyes. In addition, adsorption isotherm models were used to describe the dye adsorption process.

The prepared composite hydrogel was characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, field emission scanning electron microscopy and UV–visible.

The prepared hydrogel exhibited excellent adsorption ability for both dyes. Various experimental conditions affecting the dye adsorption were explored to achieve maximum removal of both dyes. In addition, adsorption isotherm models were used to describe the dye adsorption process.

To the best of the author’s knowledge, synthesis of PVA/poly(AAc-co-AM) composite hydrogel in the presence of Fe³⁺ and investigation of the removal of methylene blue and maxilon blue 5G dyes is done for the first time successfully.

The purpose of this paper is to examine the batch adsorption system of a cationic dye (methylene blue, widely used in various sectors) on two adsorbents; ZSM-5 zeolite which was prepared with the molar composition: 0.2057 Na₂O-0.00266 Al₂O₃-SiO₂-0.68 (pyrrolidine)-40 H₂O-0.12 H₂SO₄.

By the hydrothermal synthesis method, and the purified clay and is analyzed by IR and DRX method.

For this, the authors conducted a parametric study of adsorption and effect of several important parameters on the adsorption of BM on the material used, in particular, the contact time (equilibrium is established after 120 min), different concentrations of adsorbents, different masses, the pH and temperature. The experiments demonstrated the crucial role of these parameters. A kinetic study was done and kinetic models were applied to the experimental results such as the pseudo-first order, pseudo-second order.

This work is original.

This paper aims to focus on the development and characterization of a new electrochemical sensor, designed for the detection of methylene blue present in aqueous medium.

This sensor is obtained through the coupling of a polymeric membrane and an ion-sensitive electrode (platinum electrode). The preparation of the polymeric membrane involves the incorporation of a receptor: β-cyclodextrin (β-CD), a polymer (polyvinylchloride) and a plasticizer (dioctylphtalate). Cyclic voltammetry method (CV) was used to investigate the electrical properties of this electrochemical sensor. The effect of the experimental parameters such as dye initial concentration, scan rate, interfering elements presence and additional Nafion membrane presence was investigated in this paper.

The results are interesting because the developed sensor gives a linear response in concentrations range of 10⁻¹³ M–10⁻³ M with a good correlation coefficient of 0.979 and a detection limit of 10⁻¹³ M, which reflects the sensitivity of this sensor to the target element. The sensibility value is equal to 2. 40 µA mol⁻¹ L.

The present study has shown that the modified electrode is a very good candidate in terms of price, sensibility and reproducibility for the construction of the sensitive sensor for the control of wastewater containing methylene blue.

This paper introduced the simple synthesis process of self-cleaning coating with fog-resistance property using hydrophobic polydimethylsiloxane (PDMS) polymer and nano-calcium carbonate (nano-CaCO₃) and titanium dioxide (TiO₂).

The synthesis method of PDMS/nano-CaCO₃-TiO₂ is based on sol-gel process. The crosslinking between PDMS and nanoparticles is driven by the covalent bond at temperature of 50°C. The 3-Aminopropyltriethoxysilane is used as binder for nanoparticles attachment in polymer matrix. Two fabrication methods are used, which are dip- and spray-coating methods.

The prepared coated glass fulfilled the requirement of standard self-cleaning and fog-resistance performance. For the self-cleaning test BS EN 1096-5:2016, the coated glasses exhibited the dust haze value around 20%–25% at tilt angle of 10°. For the antifog test, the coated glasses showed the fog haze value were below 2% and the gloss value were above 85%. The obtained results completely achieved the standard antifog value ASTM F659-06 protocol.

Findings will provide an infrastructure support for the building glass to enhance building’s energy efficiency, cleaning performance and friendly environment.

This study proposed the simple synthesis method using hydrophobic polymer and nano-CaCO₃ and nano-TiO₂, which can achieve optimum self-cleaning property at low tilt angle and fog-resistance performance for building glass.

The research findings have high potential for building company, cleaning building company and government sector. The proposed project capable to reduces the energy consumption about 20% per annum due to labor cost, time-consuming and safety during manual cleaning.

The novel method to develop self-cleaning coating with fog-resistance using simple synthesis process and fabrication method for building glass application.

Combination of ASTM D 855‐56 and cationic titration methods to evolve a very rapid and precise method for the analysis of petroleum sulfonates with respect to molecular weight and sulfonate content. Active ingredient as R·SO3Na where R is a naphthenic aromatic nucleus having one side chain).

Coil‐coating process for U.K. Carrier Engineering Co. Ltd. have entered into an agreement with the Gasway Corp. of Chicago whereby Carrier will manufacture and install in this country Gasway coil‐coating equipment. The process involves the high‐speed cleaning and painting of metal in continuous‐strip form (12–60 in. wide) before fabrication. With greater availability in Britain of steel in coil form and specially‐developed paints, increasing use of coil‐coating processes are expected.

This paper aims to investigate the potential application of Balanites aegyptiaca bark powder (BABP) for removing a basic textile dye, methylene blue (MB), from aqueous solutions.

The biosorbent (BABP) was characterized using Fourier transform infrared spectroscopy (FTIR) and point of zero charge (pH_PZC). Batch mode was selected to study the biosorption of MB onto BABP surface at different experimental conditions (shaking speed, contact time, initial solution pH, ionic strength, solution temperature, biosorbent dosage and initial dye concentration). Besides, the reusability of BABP for MB biosorption was also examined.

The biosorption results revealed that approximately 96% of MB was removed successfully at the optimized operational conditions. Pseudo-second-order and Langmuir models, respectively, better described the adsorption kinetics and isotherms. The monolayer biosorption capacity (q_max) for MB was about 97.09 mg/g. According to thermodynamics findings, the MB biosorption onto BABP is an exothermic and spontaneous process. The results demonstrate that BABP can be considered as potential eco-friendly, readily available and low-cost biosorbent for hazardous textile dyes removal from water bodies and also provides a promising method for minimization of agricultural solid wastes (e.g. plant barks).

The utilization of Balanites aegyptiaca bark powder (BABP), solid waste material, as low-cost and eco-friendly biosorbent for the removal of hazardous basic textile dye (methylene blue) from the aquatic environment.

In order to discover a new adsorbent that can be used to purify dye wastewater in the textile and apparel industry, a novel type of graphene oxide/gluten composite material using an improved acid bath coagulation method was synthesized, which can remove methylene blue in an aqueous environment.

After experimentally compounding different ratios of graphene oxide and gluten, the graphene oxide/gluten composite material with 20% graphene oxide content and superlative adsorption effect was chosen. The synthesized material was characterized by different techniques such as FT-IR and SEM, indicating the microstructure of the material and the success of the composite. Various factors were considered, namely, the influence of temperature, dosage, pH and contact time. The isotherms, kinetics and thermodynamic parameters were successively discussed.

The qmax value of 214.29 mg/g of the material was higher compared to the general sorbent, thus, the graphene oxide/gluten composite material was a suitable sorbent for methylene blue removal. Overall, the graphene oxide/gluten composite material can be considered as an effectual and prospective adsorbent to remove methylene blue in the textile and apparel industrial effluent.

Graphene oxide is a potentially excellent sorbent. However, the high dispersibility of GO is detrimental to adsorption, it disperses rapidly in an aqueous solution making separation and recovery difficult. The high load capacity and recyclability of gluten as a colloid make it a suitable carrier for fixing GO. Studies on the combination of GO and GT into composite adsorption material and for the removal of dyes from dyeing wastewater have not been reported. The composite material research on GO and GT can provide new ideas for the research of these kinds of materials and contribute to its wider and convenient application in wastewater treatment.

The purpose of this paper is to improve the generation efficiency of singlet oxygen of methylene blue molecules through finely controlling their aggregation states in drug carriers.

As a photosensitiser in photodynamic therapy, methylene blue (MB) was loaded on citrate-modified hydroxyapatite (HAp) through an electrostatic interaction and followed by encapsulation of coordination complexes of tannic acid (TA) and Fe(III) ions. Ultraviolet-visible absorption spectrum of the supernatant after incubation of samples was recorded at certain time interval to investigate the release behaviour of MB. Photodynamic activity of MB was determined by the oxidation reaction of uric acid by singlet oxygen generated by MB under illumination.

Almost all MB molecules were immediately released from HAp-MB, whilst an initial burst release of MB from HAp-MB@TA was followed by a sustainable and pH-sensitised release. In comparison with HAp-MB, photocatalystic reduction of HAp-MB@TA by titanium dioxide hardly occurred under illumination, indicating the stability against reduction to leukomethylene blue in vitro. Generation efficiency of singlet oxygen by MB released from HAp-MB@TA was significantly higher than that from HAp-MB because of the control of TA and Fe(III) ions complexes on molecular structures of released MB.

A facile method was herein demonstrated to optimise the generation efficiency of singlet oxygen by controlling aggregation states of PS molecules and improve PDT efficiency to damage tumour tissues.