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The purpose of this study was to prepare carboxylated attapulgite (APT-COOH) and then be used as one of the ligands to prepare metal organic framework (MOF) hybrid materials to reduce the cost of MOF materials and improve the dispersed condition of APT. And then the materials were used to enrich anionic dye Congo red from aqueous solution.

The MOF hybrid materials were designed by means of facile reflux method rather than hydrothermal method, characterized by Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) Spectrometer and pore structure. The dispersed degree of APT-COOH in the MOF materials was validated according to adsorption efficiency for Congo red.

Due to introduction of APT-COOH, the microenvironment of the MOF materials changed, leading to different adsorption behaviors. Compared to the MOF material without APT-COOH, the adsorption capacities of the hybridized MOF materials with different amounts of APT-COOH introduced increased by 4.58% and 15.55%, respectively, as the initial concentration of Congo red solution of 300 mg/L. Meantime, hybridized MOF materials were suitable to remove Congo red with low concentration, while the MOF material without APT-COOH was appropriate to enrich Congo red with high concentration.

The microstructure of MOF hybrid materials in detail is the further and future investigation.

This study will provide a method to reduce the cost of MOF materials and a theoretical support to treat anionic dyes from aqueous solution.

APT-COOH was prepared and used as one of the ligands to synthesize MOF material to improve the dispersed degree of APT-COOH and reduce the cost of the MOF materials. The adsorption efficiency was greatly enhanced with low concentration of Congo red solution, and the results indicated that hydrogen bonding, electrostatic interaction, and p-p conjugation were involved in the adsorption process. The prepared MOFs materials exhibited excellent adsorption efficiency, which made the present materials highly promising and potentially useful in practical application as adsorbents to enrich anionic dyes such as Congo red from aqueous solution.

This paper aims to explore the adsorption kinetics of syringin from Syringa oblata Lindl. leaves on macroporous resin and develop an efficient, simple and recyclable technology for the separation and purification of syringin.

Static adsorption and desorption properties of six resins were tested to select a suitable resin for the purification of syringin. Langmuir and Freundlich isotherm models were used to estimate the adsorption behavior of syringin on AB-8 resin. Breakthrough point and eluent volume were determined by dynamic adsorption and desorption tests. High-performance liquid chromatography-electrospray ionization-mass spectrometry was applied to identify the syringin in the purified product [syringin product (SP)]. Antioxidant and antibacterial activities of SP in vitro were evaluated by free radical scavenging ability and biofilm formation inhibitory tests.

AB-8 exhibited the most suitable adsorption and desorption capacity. Adsorption isotherm parameters indicated favorable adsorption between AB-8 and syringin. The optimal results were as follows: for adsorption, the sample concentration was 1.85 mg/mL, the sample volume was 3.5 bed volume (BV), the flow rate was 0.5 mL/min; for desorption, the ethanol concentration was 70%, the elution volume was 2.5 BV, the elution velocity was 1.0 mL/min. SP with 80.28% syringin displayed the potent antioxidant activities and inhibitory effects on biofilm formation of Streptococcus suis.

To the best of authors’ knowledge, there are no reports on purifying syringin from Syringa oblata Lindl. leaves using macroporous resins. This paper may also provide a theoretical reference for the purification of other phenylpropanoid glucosides.

Water is a vital natural resource without which life on earth would be impossible. Properties of synthetic dyes like high stability and noxious nature make it difficult to remove them from the effluent. This review focuses on the removal of synthetic dyes using nanoparticles (NPs) based on the adsorption principle.

Adsorption technique is widely used to remove synthetic dyes from their aqueous solution for decades. Synthetic dye removal using NPs is promising, less energy-intensive and has become popular in recent years. NPs are in high demand for treating wastewater using the adsorption principle due to their tiny size and vast surface area. To maximise environmental sustainability, the utilisation of green-produced NPs as efficient catalysts for dye removal has sparked attention amongst scientists.

This review has prioritised research and development of optimal dye removal systems that can be used to efficiently remove a large quantity of dye in a short period while safeguarding the environment and producing fewer harmful by-products. The removal efficiency of synthetic dye using different NPs in wastewater treatment varies mostly between 75% to almost 100%. This review will aid in the scaling up of the wastewater treatment process.

There is a lack of research emphasis on the safe disposal of NPs once the reuse efficiency significantly drops. The relevance of cost analysis is equally critical, yet only a few papers discuss cost-related information.

Comprehensive and planned research in this area can aid in the development of long-term wastewater treatment technology to meet the growing need for safe and reliable water emphasising reuse and desorption efficiency of the NPs.

The purpose of this paper is to report the studies on the corrosion inhibition property of 4-amino-5-phenyl-4H-1,2,4-triazole-3-thiol (APTT) for the corrosion of 6061 Al-15 vol. pct. SiC(p) composite.

The corrosion behavior of 6061 Al-15 vol. pct. SiC(p) composite was studied at different temperatures in 0.5-M sodium hydroxide (NaOH) solution in the presence of APTT by potentiodynamic polarization (PDP) and electrochemical impedance spectroscopic techniques. The effect of inhibitor concentration and temperature on the inhibitor effect of APTT was studied. The surface morphology of the metal surface was investigated by scanning electron microscopy. The activation parameters for the corrosion of the composite and base alloy, as well as the thermodynamic parameters for the adsorption of APTT on the composite and alloy surfaces, were calculated.

The inhibition efficiency of APTT increases with the increase in the concentration of the inhibitor and decreases with the increase in temperature. The adsorption of APTT on the composite was found to be through physisorption, obeying Langmuir’s adsorption isotherm. APTT acts as a mixed inhibitor with predominant cathodic action on the composite.

APTT can be used as an inhibitor for the corrosion of 6061 Al-15 vol. pct. SiC(p) composite in the NaOH medium.

This paper provides information regarding the corrosion inhibition property of APTT on 6061 Al-15 vol. pct. SiC(p) composite. An attempt was made to explain the mechanism of the inhibition action by APTT.

This study aims to observe the coloring efficacy of graphite (G) and nano bentonite clay (BCNPs) on the adsorption of Basic Blue 5 dye from residual dye bath solution.

Some factors that affected the adsorption processes were examined and found to have significant impacts on the adsorption capacity such as the initial concentration of G and/or BCNPs (Co: 40–2,320 mg/L), adsorbent bath pH (4–9), shaking time (30–150 min.) and initial dye concentration (40–200 mg/L). The adsorption mechanism of dye by using G and/or BCNPs was studied using two different models (first-pseudo order and second-pseudo order diffusion models). The equilibrium adsorption data for the dye understudy was analyzed by using four different models (Langmuir, Freundlich, Temkin modle and Dubinin–Radushkevich) models.

It has been found that the adsorption kinetics follow rather a pseudo-first-order kinetic model with a determination coefficient (R²) of 0.99117 for G and 0.98665 for BCNPs. The results indicate that the Freundlich model provides the best correlation for G with capacities q_max = 2.33116535 mg/g and R² = 0.99588, while the Langmuir model provides the best correlation for BCNPs with R² = 0.99074. The adsorbent elaborated from BCNPs was found to be efficient and suitable for removing basic dyes rather than G from aqueous solutions due to its availability, good adsorption capability, as well as low-cost preparation.

There is no research limitation for this work. Basic Blue 5 dye graphite (G) and nano bentonite clay (BCNPs) were used.

This work has practical applications for the textile industry. It is concluded that using graphite and nano bentonite clay can be a possible alternative to adsorb residual dye from dye bath solution and can make the process greener.

Socially, it has a good impact on the ecosystem and global community because the residual dye does not contain any carcinogenic materials.

The work is original and contains value-added products for the textile industry and other confederate fields.

This paper aims to investigation of processes for Pb²⁺ elimination from water/wastewater as a significant public health issue in many parts of world. The removal of Pb²⁺ ions by various nanocomposites has been explained from water/wastewaters. ZnO-based nanocomposites, as eco-friendly nanoparticles with unique physicochemical properties, have received increased attention to remove Pb²⁺ ions from water/wastewaters.

In this review, different ZnO-based nanocomposites were reviewed for their application in the removal of Pb²⁺ ions from the aqueous solution, typically for wastewater treatment using methodology, such as adsorption. This review focused on the ZnO-based nanocomposites for removing Pb²⁺ ions from water and wastewaters systems.

The ZnO-based nanocomposite was prepared by different methods, such as electrospinning, hydrothermal/alkali hydrothermal, direct precipitation and polymerization. Depending on the preparation method, various types of ZnO-based nanocomposites like ZnO-metal (Cu/ZnO, ZnO/ZnS, ZnO/Fe), ZnO-nonmetal (PVA/ZnO, Talc/ZnO) and ZnO-metal/nonmetal (ZnO/Na-Y zeolite) were obtained with different morphologies. The effects of operational parameters and adsorption mechanisms were discussed in the review.

The findings may be greatly useful in the application of the ZnO-based nanocomposite in the fields of organic and inorganic pollutants adsorption.

The present study is novel, because it investigated the morphological and structural properties of the synthesized ZnO-based nanocomposite using different methods and studied the capability of green-synthesized ZnO-based nanocomposite to remove Pb²⁺ ions as water contaminants.

The current review can be used for the development of environmental pollution control measures.

This paper reviews the rapidly developing field of nanocomposite technology.

The purpose of this study was to the synthesis of Fe₃O₄@SiO₂ nanocomposites and using it as an adsorbent for removal of diazinon from aqueous solutions. Structural characteristics of the synthesized magnetic nanocomposite were described by Fourier transform infrared spectroscopy and scanning electron microscopy.

The effects of different parameters including pH (2-10), contact time (1-180 min), adsorbent dosage (100-2000 mg L⁻¹) and initial diazinon concentration (0.5–20 mg L⁻¹) on the removal processes were studied. Finally, isotherm and kinetic and of adsorption process of diazinon onto Fe₃O₄@SiO₂ nanocomposites were investigated.

The maximum removal efficiency of diazinon (96%) was found at 180 min with 1000 mg L⁻¹ adsorbent dosage using 0.5 mg L⁻¹ diazinon concentration at pH = 7. The experimental results revealed that data were best fit with the pseudo-second-order kinetic model (R² = 0.971) and the adsorption capacity was 10.90 mg g⁻¹. The adsorption isotherm was accordant to Langmuir isotherm.

In the present study, the magnetic nanocomposites were synthesized and used as an absorbent for the removal of diazinon. The developed method had advantages such as the good ability of Fe₃O₄@SiO₂ nanocomposites to remove diazinon from aqueous solution and the magnetic separation of this absorbent that make it recoverable nanocomposite. The other advantages of these nanocomposites are rapidity, simplicity and relatively low cost.

Corrosion is a major concern for many industries that use metals as structural or functional materials, and the use of corrosion inhibitors is a widely accepted strategy to protect metals from deterioration in corrosive environments. Moreover, the toxic nature, non-biodegradability and price of most conventional corrosion inhibitors have encouraged the application of greener and more sustainable options, with natural and synthetic drugs being major actors. Hence, this paper aims to stress the capability of natural and synthetic drugs as manageable and sustainable, environmentally friendly solutions to the problem of metal corrosion.

In this review, the recent developments in the use of natural and synthetic drugs as corrosion inhibitors are explored in detail to highlight the key advancements and drawbacks towards the advantageous utilization of drugs as corrosion inhibitors.

Corrosion is a critical issue in numerous modern applications, and conventional strategies of corrosion inhibition include the use of toxic and environmentally harmful chemicals. As greener alternatives, natural compounds like plant extracts, essential oils and biopolymers, as well as synthetic drugs, are highlighted in this review. In addition, the advantages and disadvantages of these compounds, as well as their effectiveness in preventing corrosion, are discussed in the review.

This survey stresses on the most recent abilities of natural and synthetic drugs as viable and sustainable, environmentally friendly solutions to the problem of metal corrosion, thus expanding the general knowledge of green corrosion inhibitors.

The purpose of this paper is to separate and purify flavonoids existing in the leaves of Sophora japonica by a novel method, macroporous adsorption resin (MAR) mixed-bed technology, and the optimal MAR mixed bed was screened based on the adsorption experimental result with the order of single, two, three and four MAR mixed bed separately.

The adsorption performance of MAR and MAR mixed bed for flavonoids was studied using ultraviolet – visible (UV-VIS) spectrophotometry.

This research showed that the MAR mixed bed of LZ-54 + LZ-67 with a mass ratio of mLZ-54:mLZ-67 = 1:1 was the optimized combination with the optimal conditions of adsorption (volume V = 140 mL, pH = 5, T = 35°C) and desorption (liquid ratio R = 50 per cent, T = 30°C, pH = 6) obtained, relatively.

This study aims to find an efficient way of separating flavonoids and other components that are useful for human health from Sophora japonica, which is complying with the policy of sustainable development.

This contribution provided a novel way to separate flavonoids from Sophora japonica. Under the optimal conditions, the adsorption rate (F) of MAR mixed bed LZ-54 + LZ-67 to the flavonoids was 63.65 per cent, the desorption rate (D) was 87.31 per cent and the purity was dramatically achieved at 58.17 per cent from 17.67 per cent after a round of adsorption/desorption operation.

To investigate the inhibiting effect of the cationic surfactant cetyl trimethylammonium chloride (CTAC) on aluminum (Al).

Pure aluminum rods were immersed in hydrochloric acid (HCl) and sodium hydroxide (NaOH) solutions for weight‐loss tests and potentiostatic polarization measurements.

The inhibition action depends on the concentration of the inhibitor, the concentration of the corrosive media, and the temperature. The inhibition efficiency in NaOH was higher than that in HCl solutions. In both acidic and basic media, the increase in temperature resulted in a decrease of the inhibition efficiency and a decrease in the degree of surface coverage. The results were indicative of increased aluminum dissolution with increasing temperature. It was found that adsorption of CTAC on the aluminum surface follows Temkin's isotherm in HCl and Langmuir's isotherm in NaOH.

Clarifies the effects of concentration and temperature on the inhibition efficiency of a cationic surfactant on aluminum.