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The world's water supplies have been contaminated due to large effluents containing toxic pollutants such as dyes, heavy metals, surfactants, personal care products, pesticides, and pharmaceuticals from agricultural, industrial, and municipal resources into water streams. Water contamination and its treatment have emerged out as an escalating challenge globally. Extraordinary efforts have been made to overcome the challenges of wastewater treatment in recent years. Various techniques such as chemical methods like Fenton oxidation and electrochemical oxidation, physical procedures like adsorption and membrane filtration, and several biological techniques have been recognized for the treatment of wastewater. This review communicates insights into recent research developments in different treatment techniques and their applications to eradicate various water contaminants. Research gaps have also been identified regarding multiple strategies for understanding key aspects that are important to pilot-scale or large-scale systems. Based on this review, it can be determined that adsorption is a simple, sustainable, cost-effective, and environmental-friendly technique for wastewater treatment, among all other existing technologies. However, there is a need for further research and development, optimization, and practical implementation of the integrated process for a wide range of applications.

The organic dye is one of the most problematic water pollutants in the vicinity of leather and textile industries. Adsorption method via functional materials can be considered as an effective method for dye removal from wastewater. In present work, the synthesis of mesoporous silica nanoparticles (MSNs) functionalised with histidine (MSN-His) has been reported for simultaneous removal of methylene blue (MB) and phenol red (PR) from an aqueous solution. The properties of nanoparticles were characterised in terms of size, surface area and surface modification using a scanning electron microscope (SEM), transmission electron microscope (TEM) and Fourier transform infrared (FT-IR). The influence of various factors including the contact time, the initial concentration of the adsorbate and pH of the medium on the MB and PR adsorption efficiencies were investigated. The maximum adsorption capacity was calculated to be ca. 65 mg/g for MB in basic media, and ca. 55 mg/g for PR in acidic media. The adsorption isotherm is fitted with Freundlich for all solutions. The maximum removal efficiency was ca. 70% for MB in basic media and PR in acidic media after second cycle.

The adsorption behaviour of the herbicide clomazone on inorganic and organically modified montmorillonite from the Bogovina deposit in Serbia was investigated. Montmorillonite was modified first with NaCl and then with organic complexes such as hexadecyltrimethylammonium bromide (HDTMA) and phenyltrimethylammonium chloride (PTMA). Changes in the surface properties and morphology of the montmorillonite before and after the modification with various concentrations of organic complexes were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Adsorption of clomazone on all examined samples was investigated using the batch adsorption method. Montmorillonite modified with HDTMA-bromide displayed greater uptake of the clomazone compared to the PTMA-montmorillonite, and both organically modified montmorillonites displayed greater uptake of the herbicide compared to the inorganic montmorillonite. Comparing the Freundlich coefficient and maximum adsorbed clomazone quantity values obtained by Langmuir model, the levels of adsorption of clomazone decreased in the following order: HDTMA-montmorillonite with 1.00 cation-exchange capacity (CEC) saturation > HDTMA-montmorillonite with 0.75 CEC saturation > PTMA-montmorillonite with 1.00 CEC saturation > PTMA-montmorillonite with 0.75 CEC saturation > HDTMA-montmorillonite with 0.50 CEC saturation > HDTMA-montmorillonite with 0.25 CEC saturation > PTMA-montmorillonite with 0.50 CEC saturation > PTMA-montmorillonite with 0.25 CEC saturation > Na-montmorillonite > raw sample. The type and content of an organic cation plays an important role in the behaviour of clomazone in a solid/liquid system. It is concluded that organically modified montmorillonite from Bogovina might be used as an effective adsorbent for clomazone.

Decolorization is important for wastewater treatment and product purification. Compared to an adsorption method using activated carbon and ion-exchange resin, nanofiltration (NF) is a sustainable t...

Acid mine drainage (AMD) is difficult to treat due to its physicochemical characteristics, such as high pH and high heavy metal concentrations, so it causes great harm to the environment and human health. If acid mine drainage is discharged arbitrarily without treatment, it will lead to a series of environmental problems and cause long-term environmental pollution. In this paper, the source and hazards of acid mine drainage are introduced in detail. And the principle, the mechanism, the application, and basic information of the current primary technology of the treatment for acid mine drainage are comprehensively introduced and summarized. The summarized treatment technologies for acid mine drainage mainly include neutralization, sulfidization, constructed wetland method, adsorption method, microbiological method, ion exchange method, membrane technology, and microbial fuel cell technology. Also, the primary technology of treatment for acid mine drainage is systematically compared and evaluated. Moreover, some suggestions on the development direction of water treatment technology in the future are put forward. This paper provides a scientific reference for scientific and technical works to treat acid mine drainage.

A europium salt-Na[Eu(5,5′-DMBP)(phen)3]·Cl3 (Eu(III)-CPLx) was prepared by using various precursors such as 5,5′-Dimethyl-2,2′-bipyridyl (5,5′-DMBP), 1,10-phenanthroline (phen) and europium chloride hexahydrate (EuCl3·6H2O) by a complexation method. The red emission fluorescent Na[Eu(5,5′-DMBP)(phen)3]·Cl3/D-Dextrose (Eu(III)-CPLx/D-Dex) composite was synthesized by using an adsorption method with Eu(III)-CPLx and D-Dextrose (D-Dex). The Eu(III)-CPLx and fluorescent (Eu(III)-CPLx/D-Dex) composites were characterized by numerous techniques. The fluorescent (Eu(III)-CPLx/D-Dex) composite demonstrated a strong red emission and controlled fluorescence quenching in the solid state and was consequently used in latent fingerprint (LFP) detection. The LFPs were developed by using a powder dusting method (PDM) with Eu(III)-CPLx and fluorescent Eu(III)-CPLx/D-Dex composites on different substrates under daylight and UV-light irradiation at 365 nm. The fluorescent Eu(III)-CPLx/D-Dex composite was effectively explored for developing LFP images on various substrates and also acts as a better labeling agent for LFP detection in forensic science crime scene investigations.

In this study, the effects of temperature, pH, and biochar under cadmium stress on the adsorption characteristics of atrazine in soils in northeast China were studied by batch adsorption method. In the atrazine–Cd(II) coexistence system, the adsorption of atrazine by the soils reached equilibrium within 24 h, but there were some differences in sorption capacities of the three types of soil and the order of adsorption is albic soil > black soil > saline-alkaline soil. With the concentration of atrazine increased, the adsorption capacity of atrazine in the three types of soil gradually increased, the upward trend became more obvious with the ambient temperature of the solution decreased. The adsorption kinetics curves of atrazine in the three types of soil conform to the pseudo-second-order kinetic model and the adsorption isotherm follows the Langmuir model. When atrazine and Cd(II) coexist in soils, the decrease in atrazine adsorption in the soil may be due to the competitive interaction between the two chemicals. Cd(II) occupies part of the adsorption site of atrazine, thus saturating the active site in soils. Since atrazine is a weakly alkaline pesticide, the lower the pH of the soil, the higher the affinity of atrazine for the soil. After adding biochar to the soil, the functional groups in biochar can form π bond with atrazine, which promotes the fixation of atrazine in the soil. The results show that the prevention of atrazine and cadmium leaching can be achieved by appropriately adjusting the pH, temperature, clay content, and organic matter of the soils.

Recently, there has been an increased interest in aluminosilicates of natural origin, both in connection with the application in water and soil treatment systems, and as a matrix for the creation of biologically active composites. Glauconite is an aluminosilicate widely distributed in nature, which is promising for the development of effective enterosorbents and detoxification methods. New bactericidal composites based on glauconite from the Beloozersky deposit in the Saratov region are proposed. The method of scanning electron microscopy was used to study the morphological characteristics of individual glauconite and its composites. And the trace element composition was determined by energy dispersive X-ray spectroscopy. It was also established that the nitrogen adsorption-desorption isotherms for the studied glauconite sample are of type IV according to the classification of Deming and Teller (BET classification), and the sample is characterized by the presence of mesopores from 2 to 50 nm in size. The specific surface area of enriched glauconite by BET was 22.78 m2/g, and the total pore volume (P/Po = 0.98) - 0.044 cm3/g. Composites with methylene blue, cetyl priridinium chloride and their mixture were obtained on the basis of the enriched fraction of glauconite by sorption immobilization. The sorption capacity of glauconite in relation to the above biologically active substances is determined. An increase in the antibacterial effect of the obtained composites on standard strains of Staphylococcus aureus ATCC 6538 P and Escherichia coli ATCC 25922 relative to individual substances was revealed. Thus, the work shows that glauconite and composites based on it is a promising object for creating new types of enterosorbents for subsequent use in medicine and veterinary medicine.

espanolLa zeina es una proteina no polar que tiene un elevado contenido de prolina y leucina, se puede obtener facilmente de los granos de maiz y por su composicion puede formar una matriz proteica de nanoparticulas para encapsular colorantes polares. A partir de zeina USP decolorada, se sintetizaron nanoparticulas por el metodo de dispersion liquido – liquido. La sintesis se llevo a cabo en etanol al 20% y a pH 4, condiciones que permiten la mas alta estabilidad del sistema. Se obtuvo una suspension homogenea con un tamano de particula de 282,1 nm y una polidispersion de 0,127 correspondiente a un area superficial de 18,82 m2/g; se evidencio que las particulas tienen forma esferica y no presentan porosidad. Las nanoparticulas asi obtenidas se utilizaron para encapsular antocianinas extraidas del fruto de mortino (Vaccinium floribundum Kunth) utilizando los metodos de adsorcion e incorporacion. Se determino que el metodo de adsorcion permite cargar 338,24 mg de cianidina-3-glucosido, equivalente a 172,92 g de antocianinas, por cada 100 g de nanoparticulas, comparado con el metodo de incorporacion que permitio encapsular 72,74 mg de cianidina-3-glucosido, equivalente a 37,19 g de antocianinas, por cada 100 g de nanoparticulas. Los valores de la eficiencia de encapsulacion y capacidad de carga de 32,83±2,84% y 141,38±5,41% respectivamente, permiten establecer que la zeina tiene un alto potencial encapsulante. EnglishZein is a non-polar protein that has a high content of proline and leucine, it can be easily obtained from corn grains and by its composition can form a protein matrix of nanoparticles to encapsulate polar dyes. From decolorized USP zein, nanoparticles were synthesized by the liquid-liquid dispersion method. The synthesis was carried out in 20% ethanol and pH 4, conditions that allow the highest stability of the system. A homogeneous suspension with a particle size of 282,1 nm and a polydispersity of 0.127 corresponding to a surface area of ​​18.82 m2 / g was obtained; it was evidenced that the particles have a spherical shape and do not present porosity. The nanoparticles thus obtained were used to encapsulate anthocyanins extracted from the mortino fruit (Vaccinium floribundum Kunth) using the methods of adsorption and incorporation. It was determined that the adsorption method allows to load 338.24 mg of cyanidin-3-glucoside, equivalent to 172.92 g of anthocyanins, per 100 g of nanoparticles, compared with the incorporation method that allowed to encapsulate 72.74 mg of cyanidin-3-glucoside, equivalent to 37.19 g of anthocyanins, per 100 g of nanoparticles. The values ​​of the encapsulation efficiency and load capacity allow to establish that the zein has a high potential encapsulant

Textile industry waste contains dyes that are difficult to decompose naturally and cause disruption of ecosystems in water. The colorant that is often used in the textile industry is methylene blue which is a cationic heterocyclic aromatic compound. This compound is so stable that it is difficult to decompose naturally and is harmful to the environment in large concentrations. Therefore, we need a waste treatment technology that can reduce the concentration of dye waste in water. So far, the adsorption method remains the most efficient and effective technique in removing dyes because of its relatively large adsorption capacity. One method that can be used is the adsorption method using natural zeolite. Zeolite is one of the non-metal mineral commodities or multipurpose industrial minerals, one of which is as an adsorbent or adsorbent media. This study aims to determine the potential of natural zeolite in absorbing methylene blue with variations in the concentration of methylene blue and various sizes of natural zeolite mesh. The procedures in this experiment include, the preparation of natural zeolite with size variations of 20-60 mesh, 60-100 mesh and> 100 mesh and variations in the concentration of methylene blue used 15 ppm, 30 ppm and 45 ppm with contact time from 0 to 180 minutes. From the results of the study it was found that the smaller the size of natural zeolite used, the greater the percentage of dye removal that is at mesh size> 100 mesh the percentage of dye removal was 32.11%. As for the variation of the concentration of methylene blue, the smaller the concentration, the natural zeolite can work optimally ie at a concentration of 15 ppm at 180 minutes the remaining methylene blue concentration of 0.145 ppm.

In this investigation, the removing of some substances via adsorption onto tutmaçclay were performed in aqueous and organic solutions using batch system. It was aimed toremove the inorganic ions Mg2+ and Ca2+ (Excess of; Mg2+ and Ca2+ ions make water hard andcause to serious healt problems) organic substance cholest (its removing is important as bymeans of health and cosmetically) from the solution by adsorption method using the activesurfaces of Tutmac clay was charactized by XRD. The amount of the substances adsorbed onthe clay surface in the solutions were analyzed using AAS and UV spectroscopic methods. Theexperimental data have indicated that Tutmaç clay is good adsorbent and physical adsorptionmethot is quite suitable for the removing of Mg2+, Ca2+ and cholesterol from solutions. Theadsorption data determined from experimental results best fitted Langmuir Isotherms. Theobtained results also confirmed that the applicability of Tutmaç clay is an efficient supportermaterial for removing contaminations of inorganic and organic substances. And Tutmaç claymaterial can be used as a very effective adsorbent in removing of pollutants from organic andaqueous solutions.

The colorant that is often used in the textile industry is methylene blue which is a cationic heterocyclic aromatic compound. This compound is very stable and is difficult to decompose naturally leading to environment in large concentrations. Therefore, a waste treatment technology to reduce the concentration of dye waste in water becomes importannt. So far, adsorption method with activated carbon remains the most efficient and effective technique in removing dyes from liquid waste due to its relatively large adsorption capacity. Activated carbon is one of the non-metallic mineral commodities or multipurpose industrial minerals, one of which is as an adsorbent or adsorbent media. This study aims to determine the potential of activated carbon in adsorbing methylene blue with variations in the concentration of methylene blue and particle size of activated carbon. The procedures in this experiment include, the preparation of activated carbon with size variations (20-60, 60-100 and> 100 mesh) and variations in the concentration of methylene blue (15 ppm, 30 ppm and 45 ppm) with contact time (0 to 180 minutes). From the results of the study, it was found that the smaller the size of activated carbon used, the greater the adsorption capacity, ie at mesh size> 100 mesh, the adsorption capacity was 9.8%. Whereas, the smaller the concentration of methylene blue, the activated carbon could work optimally at a concentration of 15 ppm at 30 minutes with adsorption capacity as high as 100%.Keywords: adsorption; Methylene Blue; activated carbon; concentration; time; particle size

Using steel slag as a raw material, a new type of adsorption material has been prepared by acid modification method. The preparation conditions of modified steel slag, and the adsorption performance of the modified steel slag for uranium were analyzed by static adsorption method. Results showed that the adsorption efficiency of modified steel slag for uranium was 98.5% under the best condition. In addition, the modified steel slag was also characterized before and after modification by SEM–EDS, BET, FTIR, ICP-OES. The hydroxides and BET of the modified steel slag increased significantly, which was more conducive to the adsorption of uranium on modified steel slag.

Highly dispersed ultrafine Pt nanoparticles were supported on halloysite nanotubes by a strong electronic adsorption method. The as-prepared nanocatalyst showed excellent catalytic performance with...

In this work, potato peel wastes were used as absorbents to remove heavy metals (Cu +2 and Fe +3) from aqueous solutions using adsorption method.

Nowadays water bodies across the world are heavily polluted due to uncontrollable contamination of heavy metal particles, toxic dyes, and other harmful wastes discharged by emerging industries other than normal domestic wastages. This contamination needs sufficient control to protect the natural water bodies. There are various methodologies to be followed to perform wastewater treatment, in which the adsorption method of filtration is found to be efficient. The adsorption method is a high priority and preferable filtration method compared to other waste water treatment methods due to its peculiar characteristics. Considering the adsorption method, there are multiple options available in selecting material and methodology for the filtration process. In selecting the filtering material, there is much attraction towards graphene and its oxides, which have widespread range of differential applications in commercial industries because of their eco-friendly characteristic features. The importance of various graphene composites and their chemical properties is found to be significant in various fields. Analyzing the adsorbing properties of graphene widely, this article deeply reviews about the improvements and the technologies identified for using graphene and (GO) graphene oxide in wastewater treatment taken into discussion elaborately. Therefore, in this hard review, the advantages and demerits of using graphene for wastewater treatment as well as improving its properties to make it more suitable for wastewater treatment are detailed.

This work focuses on the catalytic potential of K-impregnated staghorn coral as a catalyst in methyl esters production via methanolysis of waste cooking oil (WCO). The prepared catalyst was analyzed by Hammett indicators, XRF, Brunauer-Emmett-Teller (BET)-N2 adsorption method, ATR-FTIR, TGA, XRD and SEM to determine its physicochemical properties. ATR-FTIR and XRD results confirmed the formation of K2O species upon KOH impregnation, thus, resulting in good catalytic activity. Reaction parameters such as methanol to oil ratio, reaction time and amount of catalyst were evaluated to find out the best conditions for the transesterification process. About 89.51 ± 4.78 % of biodiesel contents were obtained under the optimum conditions.

The objective of this study was to explore the feasibility of using nanocrystal technology for the design of immediate and sustained release tablets of poorly water soluble drugs. Nanocrystal aggregates comprised of lovastatin, a model drug, 20% PVP K17 and 5% SDS were prepared by spray drying. The nanocrystal aggregates were mixed with lactose, Avicel Ph 101 and Ac-Di-Sol® (blank granules) or 316 Fast Flo® lactose, MCC PH200, and Ac-Di-Sol ® (direct compression), where the composition was optimized by uniform design. The blank granules adsorption method had superior flowability, filling and plastic deformation as well as rapid release rates, and the tableting process did not affect the release rate of nanocrystals. An optimized sustained release tablets formulation was also identified, which decreased the difference of drug release behavior under sink and non-sink conditions. In conclusion, nanocrystal technology is promising for preparing both immediate and sustained release tablets for poorly water soluble drugs with robust drug dissolution and release.

Protein-silica composites are a promising platform for the development of new dosage of protein drugs. The sol-gel method was used to synthesize bovine serum albumin composites with colloidal silica in the presence and absence of trehalose as a protein structure stabilizer. The structural state of the protein in the composites and after release from them and the kinetics and mechanisms of in vitro release were studied. The functional properties of the sol-gel composites were compared with similar composites obtained by the adsorption method. The strong effect of the synthesis method and the influence of trehalose on the structure of the protein and the kinetic parameters and mechanisms of its release were shown. On the basis of a comparative analysis, it was concluded that sol-gel composites have a number of advantages over adsorption-derived composites in terms of their functioning as delivery systems of protein drugs.

The ship wall-climbing robot belongs to a branch of intelligent robots, and its application objects are large military and civilian ships. It is mainly engaged in special operations such as testing, welding, cleaning and descaling. With the rapid development of science and technology, ship wall-climbing robots have also developed from the original negative pressure adsorption wall-climbing robots to the current bionic foot-type wall-climbing robots. In practical applications, it is gradually replacing manual operations, greatly improving work efficiency. This article introduces various ship-climbing robots with adsorption, movement, and driving methods as the main categories. This article focuses on the magnetic adsorption method, combined with other adsorption methods, and analyzes the performance characteristics and existing problems of various wall-climbing robots. Finally, we summarize the current technical problems of wall-climbing robots, and then make a prospect for the future development of wall-climbing robots.

Development of the industry, especially the palm oil mill industry, it will have an impact with tangible evidence that makes the environment polluted. Heavy metals will be produced from the palm oil mill industry and will pollute the environment. Zn metal is one of the heavy metal waste produced from the mustard coconut factory industry. Zn heavy metal waste will be very dangerous if it exceeds a predetermined level and will have an impact on humans, animals and the environment. One effort to reduce heavy metals using the adsorption method. Adsorption has advantages over a variety of other methods. Adsorban that is used from materials found in nature and the resulting waste can be used as an adsorbent. The type and type of adsorbent greatly affect the pH adsorption level of the Zn metal solution.

In the article, the treatment of pre-treated laundry wastewater by adsorption method was studied through the experimental design. The composites of the polyaniline-supported activated carbons produced from sunflower seed hulls (PAn/SH) were used as adsorbents. Characteristics of the adsorbents were determined with the help of scanning electron microscopy, Fourier-transform infrared spectroscopy and elemental analysis. Experimental design was used to determine the effects of pH (4-12), reaction time (5-150 min), adsorbent amount (0.3-1.5 g) and mixing rate (50-200 rpm) on the process efficiency. Monitoring of the efficiency was held in terms of detergent and chemical oxygen demand removals. Response surface methodology based on the four-variable-three-level Box-Behnken design was used to interpret the adsorption properties of laundry wastewater on COD and detergent removal efficiencies. The removal efficiencies of the adsorption process were evaluated regarding to the experimental design and also Pareto analysis was applied for profiling the percentage effect of the independent variable on the response for the study. Accordingly, the most effective factors were computed as the amount of adsorbent (82%) in detergent removal and the mixing rate (31%) in COD removal, where pH was the second effective factor for both. The highest efficiencies of the MBAS and COD removals were achieved as 95% and 74% in the 24th run, respectively. In the treatment of laundry wastewater by adsorption method, using PAn/SH produced from the sunflower seed hulls as an adsorbent will be an alternative method. TUBITAK Research and Development ProgramTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [115Y797, 115Y820] This work was supported by the TUBITAK Research and Development Program with Priority Fields [the main Project 115Y797 and sub-Project 115Y820]. WOS:000624994000001

In this study, recovery of rubidium(I) with potassium cobalt hexacyanoferrate (K2[CoFe(CN)6]) was studied by adsorption method. For the adsorbent characterization, XRD and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) analyzes were performed and FAAS was used for the elemental analysis. The Rb(I) ion adsorption onto the adsorbent from aqueous solution was investigated under the different experimental conditions such as pH, adsorbent dosage, contact time and temperature. One mole of NaOH was used as eluent for the recovery of rubidium(I) onto the adsorbent. The results showed that K2[CoFe(CN)6] was a suitable and efficient material for high Rb(I) adsorption capacity from boron industrial waste. © 2019 Taylor & Francis.

Tekstil endüstrisi boyama proseslerinde bol miktarda su, kimyasal madde ve boyar madde kullanılmaktadır. Boyama süreçlerinde kullanılan çıkış sularının alıcı ortamlara verilmeden önce arıtılması ve geri kazanımı ekolojik olarak hayati önem arz etmektedir. Adsorpsiyon yöntemi ile arıtma uygulamalarında, düşük maliyetli ve kolay elde edilebilen adsorbanlar tercih edilmektedir. Aktif karbon, yüzey alanı geniş ve adsorplama kapasitesi yüksek olan önemli bir adsorban türü olup karbon içerikli pek çok organik atıktan elde edilebilmektedir. Boyalı atık suların renk gideriminde sıklıkla aktif karbon kullanılmaktadır. Bu çalışmada ceviz kabuğundan farklı aktivasyon koşullarında elde edilen aktif karbonlar kullanılmıştır. Adsorpsiyon için en uygun yüzey özelliklerine sahip olan aktif karbon belirlenmiş ve deneylerde metilen mavisi giderimi için kullanılmıştır. Yapılan adsorpsiyon deneylerinde, adsorban konsantrasyonu, sıcaklık, pH ve adsorpsiyon süresi gibi parametrelerin boya giderimi üzerinde etkisi incelenmiştir. Son olarak elde edilen veriler Langmuir ve Freundlich izoterm modellerine uygunlukları bakımından değerlendirilmiştir. Copious amounts of water, chemicals and dyeing materials are used in dyeing processes in textile industry. It is ecologically vital to treat and recycle the discharge liquids used in dyeing processes before they are given to receiving environments. Low cost and easily obtainable adsorbents are preferred in treatment applications with adsorption method. Activated carbon is an important adsorbent with a large surface area with high adsorption capacity and can be obtained from many carbon-containing organic wastes. Activated carbon is frequently used in the color removal of dyed wastewater. In this study, activated carbons obtained from walnut shell under different activation conditions were used. Activated carbon, which has the most suitable surface properties for adsorption, was identified and used for removal of methylene blue in experiments. In the adsorption experiments, the effect of parameters such as adsorbent concentration, temperature, pH and adsorption duration on dye removal was investigated. Finally, the data obtained were evaluated in terms of their suitability to the Langmuir and Freundlich isotherm models.

Fluoride pollution in subsurface water is a significant problem for different nations across the world because of the intake of excessive fluoride caused by the drinking of the contaminated subsurface. Water pollution by flouride can be attributed to the natural and human-made agents. Increased levels of fluoride in drinking water may result in the irretrievable demineralization of bone and tooth tissues, a situation called fluorosis, and other disorders. There has long been a need for fluoride removal from drinking water to make it safe for human use. Among the various fluoride removal methods, adsorption is the method most popularly used due to its cheap cost, ease of utilization, and being a scalable and simple physical technique. According to the findings of this study, the highest concentration of fluoride (0.1–15.0 mg/L) was found in Sweden and the lowest (0.03–1.14 mg/L) in Italy. We collected the values of adsorption capacities and fluoride removal efficiencies of various types of adsorbents from valuable released data accessible in the literature and exhibited tables. There is still a need to find the actual possibility of using biosorbents and adsorbents on a commercial scale and to define the reusability of adsorbents to decrease price and the waste generated from the adsorption method. This article reviews the currently available methods and approaches to fluoride removal of water.

The development of innovative methods to prepare graphene-based polymer composites with remarkable properties has become a priority due to the many practical applications of these microstructures. Herein, a new technology was used to fabricate composites by combining graphene materials and polymer microspheres. Polyamide 6 (PA6) microspheres were synthesised by reaction-induced phase separation method, and they were wrapped with few-layer graphene (FLG) or graphene oxide (GO) by exfoliated adsorption method, which allows FLG and GO sheets to form a three-dimensional network structure in the PA6 matrix. Electrical and mechanical characterisation led to a distinct improvement in the properties of PA6 composites, which were superior to traditional graphene/polymer composites. Moreover, the process proposed in this work proved to be an effective method to prepare graphene/polymer composites, suitable for industrial production, and can be extended to other kinds of composites with nanofillers.

Methylene blue removal by adsorption method had been done in batch method using adsorbent of used paper powder. Adsorption parameters covering adsorbent doses, contact times, pH, adsorbate concentrations and adsorption isotherm as well as desorption study of the absorbed methylene blue were evaluated. The results showed the highest adsorption of methylene blue was obtained at an optimum adsorbent dose, for 30 min at pH > 9. The maximum adsorption capacity of 30.77 mg/g was obtained with Langmuir isotherm model. While the effective methylene blue desorption on the used paper powder adsorbent was obtained c.a. 0.27 mg/g at pH 1.

Stabilization and immobilization on a proper support is essential in processing and production of enzymes. Luciferase is an unstable, thermally sensitive, and light-emitting enzyme that requires stabilization for efficiency and productivity in bio-luminescence reactions. In this work, a known and well-porous framework, MIL-53(Al), was used, for the first time, to support the immobilization of firefly luciferase. Interestingly, all the stability values were improved through the immobilization process, and the content of the loading enzyme on MIL-53(Al) was found to be significant. The results obtained indicated that the stabilization of firefly luciferase on MIL-53(Al) proceeded through the adsorption method. MIL-53(Al) was also characterized by the FT-IR, X-ray diffraction, FE-SEM, TEM, BET, and TGA techniques in order to determine the carboxylic groups and symmetric/asymmetric CO2, percentage of crystallinity and its purity, morphology, size, and shape of the MIL-53(Al) particles, and surface-to-area ratio and thermal gravimetry of support.

Pesticides have been always restricted by poor efficacy and inacceptable toxicity. In this work, a pH-sensitive controlled-release nano-capsule of fungicide, Boscalid@ZIF-67 (ZIF is a subclass of MOF), was prepared based on metal-organic framework (MOF) for higher antifungal effect and low bio-toxicity. The Boscalid@ZIF-67 was formed by physical adsorption method and it possesses uniform size and dodecahedral shape. The loading ratio is as high as 18%. In addition, the release of fungicide Boscalid showed pH sensitive response due to the weak acidic group in the MOF structure, in which the rate of release was more rapid under acid condition (＜7). Cumulative release rate release was higher about 25% and 38% adjusted from 7 to 3.5 and from 7 to 5.5 on the 6th day than that under neutral condition. At the early stage of infecting the host plant, Botrytis cinerea will produce more acidic substances such as oxalic acid, which are conducive to Boscalid@ZIF-67 disintegration for rapid release of Boscalid. Meanwhile, the antifungal effect of Boscalid@ZIF-67 was 4-6 times more of that commercially available product on Botrytis cinerea, while the bio-toxicity under the same condition is much lower than that of latter. Thus, this work not only proves that Boscalid@ZIF-67 could be used as nanoparticles platform for smart control over Botrytis cinerea, but also has great potential to improve traditional modalities by addressing the crop diseases in economic and ecological manner.

This study reports on the synthesis and characterization of sericin–dimethylolurea films (SS–DMU) and the immobilization of Burkholderia cepacia LTEB11 lipases through the so-called “sandwich” adsorption method, wherein the enzyme is deposited on the film, forming an enzyme–film–enzyme surface. Measured film thicknesses were between 230 and 309 μm. Resistance to traction was approximately double in comparison to the film with no enzyme applied. Scanning electron microscopy images attest the formation, after the enzyme immobilization, of aggregate deposits, possibly proteins, over the film surface. Catalytic efficiency was ascertained in ethyl oleate esterification reactions. Ester yield was practically equal (96%, 24 h) for the free and immobilized enzymes. Film samples with different quantities of lyophilized enzyme deposits (56, 122 and 156 mg) were analyzed; during the first 5 h of observation the sample with the largest quantity showed faster reaction speeds. The immobilized lipase (56 mg) was reused, and catalytic efficiency decreased to 58% after seven reaction cycles. The results point to SS–DMU film as a promising biocatalysis material.

The data in this article were obtained from a research designed to investigate the effects of choice of solvent, mixing speed, temperature and solvent to oil ratio on the treatment process of used lubricating oils using solvent extraction and adsorption method. Various data on the performance of the three solvents chosen were studied and compared based on certain parameters are presented and discussed. From the results obtained, it was observed that MEK (Methyl Ethyl Ketone) had the best performance because it gave the highest sludge removal and closest properties to the fresh lubricating base stock. Furthermore, it was also determined that increase in temperature improved the quality of oil obtained up till 50 °C above this temperature poorer quality of oil was observed. But above all the factors investigated, it was concluded that solvent to oil ratio has a greater effect on the quality of oil produced after treatment. Keywords: Used lubricating oil, Solvent extraction, Adsorption, Treatment, Sludge, Characterization

This article proposes a novel sodium dodecylbenzenesulfonate (SDBS)-assisted equilibrium adsorption method for preparing highly dispersed Ni/Al2O3 and Fe-promoted NiFe/Al2O3 thioetherification catalysts. The proposed strategy anchors nickel cations onto the electronegative surface of an Al2O3 support modified by negatively charged DBS− bilayers. As a result, this method achieves highly dispersed Ni nanoparticles without strengthening the metal-support interaction, promoting the reducibility and sulfurization of the supported Ni species. The as-prepared Ni-based catalysts have a smaller size, a higher dispersion of metal nanoparticles, and a greater amount of active metal sulfides than their counterparts prepared by the conventional impregnation method, endowing them with excellent catalytic performance for the highly selective removal of mercaptans. This method provides a new opportunity to prepare highly dispersed metal nanoparticles without a strong metal-support interaction.

Seven types of activated carbon were used to investigate the effect of their structure on separation of CO2 from (H2 + CO2) gas mixture by the adsorption method at ambient temperature and higher pressures. The results showed that the limiting factors for separation of CO2 from 53.6 mol% H2 + 46.4 mol% CO2 mixture and from 85.1 mol% H2 + 14.9 mol% CO2 mixture were different at 20 °C and about 2 MPa. The best separation result could be achieved when the pore diameter of the activated carbon ranged from 0.77 to 1.20 nm, and the median particle size was about 2.07 µm for 53.6 mol% H2 + 46.4 mol% CO2 mixture and 1.41 µm for 85.1 mol% H2 + 14.9 mol% CO2 mixture. The effect of specific area and pore diameter of activated carbon on separation CO2 from 53.6 mol% H2 + 46.4 mol% CO2 mixture was more significant than that from 85.1 mol% H2 + 14.9 mol% CO2 mixture. CO2 in the gas phase can be decreased from 46.4 mol% to 2.3 mol%–4.3 mol% with a two-stage separation process.

This article describes the preparation of calix[4]arene-bonded silica gels (C[4]BS and DMC[4]BS), and their application to the removal of some selected phenolic compounds such as phenol (PHE), p-chlorophenol (PCP), m-nitrophenol (MNP) and p-nitrophenol (PNP) from aqueous solutions by adsorption method. In initial adsorption experiments appeared that C[4]BS was much more effective in adsorption of PNP rather than PHE, PCP and MNP, whereas DMC[4]BS exhibited too little adsorption ability towards all phenols. Herein, it was concluded that the hydrogen bonding capacities of both phenols and calix[4]arene based adsorbents played a predominant role in the interactions between adsorbate and adsorbent within the adsorption mechanism. Thus, in subsequent studies, the C[4]BS was employed as an adsorbent in the adsorption of PNP, and adsorption conditions were optimized. Furthermore, isotherm and kinetic studies were performed to clarify the phenomena of PNP adsorption onto C[4]BS.

Polydopamine polystyrene nanofibers mat (PDA-PS NFsM) was prepared as an adsorbent for the simultaneous removal of multiple antibiotic residues in environmental water for the first time. PDA-PS NFsM can directly be used to adsorb 18 antibiotic residues belonging to 8 classes without any pretreatment of water samples. The adsorption process was completed within 5 min. All antibiotics could be removed at the same time, and the removal rate of each target was above 85%. Moreover, the used PDA-PS NFsM can be easily separated from the environmental water by taking out directly, and can be reused for 10 times after simple regeneration. The thermodynamic and kinetic properties of PDA-PS NFsM adsorption of antibiotic residues were further investigated consequently. It was found that the adsorptions of PDA-PS NFsM to the targets were spontaneous and endothermic process (ΔG 0, ΔS>0). The results of adsorption kinetic experiments illustrated that the adsorption process was rapid, the adsorption equilibrium of which can be reached in 5 min. Adsorption isotherm experiments proved that the adsorption process of PDA-PS NFsM was consistent with Langmuir adsorption (R2 > 0.994), and the maximum adsorption capacity of PDA-PS NFsM towards all targets were 123.76 mg g−1. The developed method is rapid and simple, and can efficiently adsorb and remove a variety of antibiotics in environmental water, which has good practical application prospect.