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In this article, attapulgite (ATP) as a raw material, hexadecyltrimethylammonium bromide (CTAB) as a modifier, and chitosan (CTS) as a composite are used to prepare a natural mineral-based composite adsorbent CTAB-ATP/CTS for the adsorption of norfloxacin in water. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and specific surface area (BET) were used for characterization. When the initial pH is 7, the dosage of adsorbent is 3 g/L, and the initial concentration of norfloxacin is 50 mg/L, the reaction temperature is 25 °C, the shaking time is 4 h, and the maximum removal rate and adsorption capacity of CTAB-ATP/CTS for norfloxacin reached 94.62% and 23.66 mg/g, respectively. The adsorption of norfloxacin by CTAB-ATP/CTS is more consistent with the pseudo-second-order kinetic model (R2 = 0.9999, 0.9998, 0.9999 at initial concentrations of 25 mg/L, 50 mg/L, 75 mg/L), and the Langmuir isotherm adsorption model(R2 = 0.9903, 0.9935, 0.9933 at temperatures of 25 °C, 30 °C, 35 °C), indicating that the adsorption process of the composite material is controlled by chemical adsorption and its adsorption behavior is mainly single-layer adsorption. [ABSTRACT FROM AUTHOR]

As people's material quality of life continues to improve, water resources become subjected to varying degrees of contamination. As one of the most commonly utilised agents in water treatment, a flocculant exhibits a diverse range of forms and a vast scope of applications. However, the application of flocculants gives rise to a series of issues, including the use of large doses, the formation of sludge, the difficulty of recycling flocculants, and other concerns. The development of new flocculation technology has become a crucial step in enhancing the purification of wastewater and reducing environmental pollution. Magnetic flocculation can be classified into two main categories: magnetic seeds flocculation and magnetic flocculation. This paper presents an overview of the factors influencing magnetic flocculation, including the type of magnetic seeds, magnetic seeds particle size, and other pertinent considerations. Furthermore, the classification of magnetic flocculants in the process of magnetic flocculation is discussed. This includes the types of magnetic flocculant, namely, inorganic composite magnetic flocculants, organic composite magnetic flocculants, and biological composite magnetic flocculants. Inorganic composite magnetic flocculants are inexpensive and simple to produce; however, their dosage is considerable, and the resulting floc is not tightly formed, which impairs the efficacy of flocculation. The use of organic composite magnetic flocculants requires a smaller dosage and exhibits a strong flocculating ability; however, it may possess toxic properties and potentially cause harm to the water body. The biological composite magnetic flocculant exhibits high efficiency and no pollution, yet it is subject to stringent environmental conditions, displays poor stability, and is applicable to a relatively limited range of treatment scenarios. Furthermore, the integration of magnetic flocculation technology with other techniques is classified and summarised in diverse contexts, and the prospective research focus and direction of magnetic flocculants are proposed. [ABSTRACT FROM AUTHOR]

Red mud was modified by impregnation with Co element loading. The Co-RM catalyst was characterized using scanning electron microscopy (SEM), X-ray powder diffraction (XRD), X-ray fluorescence (XRF), and UV full-band scanning. The results showed that the modified Co-RM catalyst successfully loaded the Co element and formed an irregular pore structure on the surface, thereby increasing the number of active sites of the red mud catalyst and effectively improving the degradation efficiency of tetracycline. Under the optimal conditions of a catalyst dosage of 0.3 g/L, a persulfate dosage of 3 g/L, a reaction temperature of 50 °C, and a pH value of 7, a removal rate of 50 mg/L of tetracycline can be achieved: 89.5% after 90 min. The effects of common anions and humic acids in water, as well as radical quenchers (anhydrous ethanol and tert-butanol), on the degradation of tetracycline were investigated. The results showed that Cl−, CO32−, HCO3−, H2PO4−, NO32−, HPO42−, and humic acids showed inhibitory effects on the degradation of tetracycline, while SO42− showed a promoting effect on the degradation of tetracycline. The free radical quenching experiment showed that the most important free radicals that can degrade tetracycline in the system are sulfate radicals. [ABSTRACT FROM AUTHOR]

Odor is one of the most intuitive indicators for assessing drinking water quality in waterworks. Removing odors is of great importance to improve the quality of tap water, ensure people's health, and address public perception. The effective identification of odors in drinking water and the exploration of the source of the odor are the prerequisites for eliminating odors. Therefore, this article first discusses the sources and types of odors that are typical in current drinking water, focuses on reviewing the research progress of odor removal technologies in water treatment plants, including adsorption technology, chemical oxidation technology, biodegradation technology and combined technology, and explains the advantages, disadvantages, principles, research progress, practical application scenarios, considerations and application prospects of each odor-removal technology. It is expected to provide a reference for controlling odor pollution in drinking water. [ABSTRACT FROM AUTHOR]

Natural clay mineral and its modifier called modified clay have been used in many environmental applications for a number of years. However, they are not capable enough to achieve a higher conversion rate and so-called ecological sustainability. This can be due to a lack of understanding of the selectivity of the clay and its modifier or a lack of compatibility between clay and pollutants. Recently, the development and implementation of green principles into practice have become an emerging field that brings together green chemistry and engineering practices to achieve a pollutant-free environment (air, water, and soil). This review summarizes the role of clay/modified clay in pollution control and discusses the role of green chemistry in creating global sustainability. In this context, this review sheds light on the complete classification of the clay family to identify its properties and to critically examine the applicability of clay and modified clay for air, water, and soil pollution control over the past decade. This is the unique point of this review, showing how the properties of clay/modified clay can be useful for removing any type of pollutant without focusing on a single type of pollutant or clay. Furthermore, the importance of green materials in clay research, as well as the future area of application, was discussed. Overall, this review places value on multidisciplinary researchers to determine the role of the green pathway in the application of clay and modified clay in achieving environmental sustainability. [ABSTRACT FROM AUTHOR]

As an abundant potentially dangerous waste, red mud (RM) requires a straightforward method of resource management. In this paper, an RM catalyst loaded with cobalt (Co-RM) was prepared by the coprecipitation method for the efficient activation of persulfate (PS). Its degradation performance and mechanism of ofloxacin (OFL) were investigated. The characterization results of scanning electron microscopy, X-ray diffractometer, and energy dispersive spectrometer showed cobalt was successfully loaded onto the surface of RM, and the catalyst produced could effectively activate PS. Under the conditions of 15 mg/L OFL, 0.4 g/L Co-RM, 4 g/L PDS, 3.0 pH, and 40 °C temperature, the maximum removal rate of OFL by the Co-RM/PDS system was 80.06%. Free radical scavenging experiments confirmed sulfate radicals were the main active substances in the reaction system. The intermediates in OFL degradation were further identified by gas chromatography-mass spectrometry, and a possible degradation pathway was proposed. Finally, the relationship between defluorination rate and time in the Co-RM/PDS degradation OFL system was described by the first-order kinetic equation. This work reports an economical, environmental solution to the use of waste RM and provides a research basis for the further exploration of RM-based catalysts. [ABSTRACT FROM AUTHOR]

A Y-type zeolite was prepared from illite clay, which was activated and synthesized by a solid-phase alkali fusion technique with reduced reaction conditions and crystal methods. The optimal synthesis conditions were investigated using the Box-Behnken design for a NaOH/illite (mass ratio) of 1:2, an activation temperature of 185 °C, and an activation time of 2.7 h. The synthesized Y-type zeolites were characterized by various analytical techniques such as FT-IR, XRD, and SEM, and the results obtained show that small amounts of quartz and P-type zeolites are present in the synthesized products. The mixture was classified as a zeolitic mineral admixture (ZMA). The adsorption performance of ZMA on Pb(II) and Cu(II) in solution was evaluated by batch adsorption experiments. The results showed that ZMA had good adsorption performance for Pb(II) and Cu(II), with maximum adsorption amounts of 372.16 and 53.46 mg/g, respectively. From the investigation, it was concluded that the adsorption process is chemisorption occurring in monomolecular layers and relying on electrostatic adsorption, ion exchange and complexation of hydroxyl groups on the ZMA surface for heavy metal cations. The ZMA reusability result shows that sodium chloride has the ability to regenerate the active site by restoring the ion exchange capacity without significant loss of Pb(II) and Cu(II) adsorption. [ABSTRACT FROM AUTHOR]

Therapy resistance remains one of the major challenges for cancer treatment that largely limits treatment benefits and patient survival. The underlying mechanisms that lead to therapy resistance are highly complicated because of the specificity to the cancer subtype and therapy. The expression of the anti-apoptotic protein BCL2 has been shown to be deregulated in T-cell acute lymphoblastic leukemia (T-ALL), where different T-ALL cells display a differential response to the BCL2-specific inhibitor venetoclax. In this study, we observed that the expression of anti-apoptotic BCL2 family genes, such as BCL2, BCL2L1, and MCL1, is highly varied in T-ALL patients, and inhibitors targeting proteins coded by these genes display differential responses in T-ALL cell lines. Three T-ALL cell lines (ALL-SIL, MOLT-16, and LOUCY) were highly sensitive to BCL2 inhibition within a panel of cell lines tested. These cell lines displayed differential BCL2 and BCL2L1 expression. Prolonged exposure to venetoclax led to the development of resistance to it in all three sensitive cell lines. To understand how cells developed venetoclax resistance, we monitored the expression of BCL2, BCL2L1, and MCL1 over the treatment period and compared gene expression between resistant cells and parental sensitive cells. We observed a different trend of regulation in terms of BCL2 family gene expression and global gene expression profile including genes reported to be expressed in cancer stem cells. Gene set enrichment analysis (GSEA) showed enrichment of cytokine signaling in all three cell lines which was supported by the phospho-kinase array where STAT5 phosphorylation was found to be elevated in resistant cells. Collectively, our data suggest that venetoclax resistance can be mediated through the enrichment of distinct gene signatures and cytokine signaling pathways. [ABSTRACT FROM AUTHOR]

Niobium pentachloride functionalised perlite was prepared via a solid state dispersion technique, which was utilized as an efficient heterogeneous catalyst for the synthesis of pyrans. The immobilisation of NbCl5 over perlite was examined by Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), Thermogravimetric analysis (TGA), scanning electron microscope (SEM) with energy dispersive spectra (EDS), and Brunauer, Emmett and Teller (BET) surface area measurements. The wt% of NbCl5-loaded perlite was optimized based on the adequacy with respect to the yield of the pyrans in various solvents. The recyclability of the catalyst was validated in synthesizing pyrans and the results marked its efficiency up to five runs. The efficacy of the NbCl5/perlite catalyst was found to be comparable and better with respect to the other heterogeneous catalysts reported. The structures of pyrans were confirmed by FT-IR, 1H and 13C NMR spectral techniques. The proposed recyclable heterogeneous NbCl5/perlite catalyst simplifies the protocol, and has minimal chemical waste, a lower reaction time and a high-yield. [ABSTRACT FROM AUTHOR]

The global panic caused by COVID-19 has continued to increase people's demand for masks. However, due to inadequate management and disposal practice, these masks have, unfortunately, entered the environment and release a large amount of microplastics (MPs), posing a serious threat to the environment and human health. Understanding the occurrence of mask waste in various environments, release of mask-origin MPs, and related environmental risk is essential to mask-waste management in current and future epidemic prevention and control. This paper focuses on the global distribution of mask waste, the potential release of waste-origin MPs, and the impact on the environment. Specifically, the physical and chemical properties of polypropylene (the most common plastic material in a mask), which show a high adsorption capacity for heavy metals and organic pollutants and play a role as a support for microbial growth, were extensively reported. In addition, several important issues that need to be resolved are raised, which offers a direction for future research. This review focuses on the essentiality of handling masks to avoid potential environmental issues. [ABSTRACT FROM AUTHOR]

Constructed wetlands have been applied to micro-polluted rivers and lakes. However, they often show poor nitrogen removal efficiency due to insufficient carbon sources for complete denitrification in the waters. In this study, a vertical-flow wetland system was built, in which reeds as a carbon source were added in the middle layer of the substrate. Thereby, the effect of the reed carbon source on denitrification of micro-polluted rivers and lakes with a low C/N ratio in the wetland and the denitrification mechanism were studied. The results showed that the concentrations of NH4+-N, NO3−-N and NO2−-N in the effluent of the constructed wetland were reduced to 0.17–0.35, 0.20–0.49 and 0.01–0.02 mg/L after adding the reed carbon source, and the removal efficiencies of the system for NH4+-N and NO3−-N reached 93.84% and 84.69%, respectively. The abundances of nirK, nirS, hzo and nrfA genes in the wetland substrate increased by 95.51%, 54.96%, 52.89% and 731.95%, respectively, which was considered to be related to the enhanced denitrification, anammox and dissimilatory nitrate reduction to ammonium of the wetland system. Reed planting promoted the increased abundances of amoA and nxrB genes, which might play a positive role in enhancing nitrification in wetland systems. The result of this study may provide a theoretical basis for the ecological restoration of low C/N micro-polluted water bodies. [ABSTRACT FROM AUTHOR]

We explored the occurrence and distribution of nonylphenol (NP) in 13 Taiwanese source waters. From all the surveyed waters, NP was detected at a high concentration, which could be attributed to contamination by wastewater discharges. In this study, we applied modified multi-walled carbon nanotubes (MWCNTs) for removing NP from aqueous solution. The impact of a few experimental factors, i.e., pH, contact time, MWCNTs dose, and temperature on the NP removal efficiency of modified MWCNTs was studied. The maximum adsorption capacity of the MWCNTs was observed to be 1040 mg NP/g when the initial NP concentration was 2.5 mg/L, and the solution pH was 4. The adsorption process followed the Elovich kinetics and the Elovich isotherm, indicating it is multilayer adsorption. The thermodynamic analysis demonstrated the NP adsorption by MWCNTs was thermodynamically satisfactory and, for the most part, endothermic as in the case of phenol adsorption. The result of the current study demonstrated the significance of free binding sites and the pore size of MWCNTs in the NP adsorption. This paper will help to better comprehend the adsorption behavior and mechanism of alkyl phenolic compounds onto MWCNTs. [ABSTRACT FROM AUTHOR]

In this work, a silane modifier with benzyl substitutes (OFS-B) and linear substitutes (OFS-L) was used to modify bentonite clay and soil, and the results were characterized by Fourier transform-infrared absorption spectroscopy (FT-IR) and powder-X-ray diffraction (XRD) analysis. A contact angle analysis was performed to determine the wettability of modified clay and soil. The findings revealed that silane-modified OFS-L clay and soil produced wettable surfaces, while OFS-B exhibited hydrophobic properties. These clays and soils were used in a bioretention system for Cd (II) removal. In the study, seven different types of bioretention systems, including natural, OFS-L, and OFS-B modified clay and soil, as well as natural, OFS-L, and OFS-B modified soil, were applied to Cyperus alternifolius plants without an additional layer. The removal capacity of Cd (II) was measured in the following order: modified clay > modified soil > original clay/soil > no layer, i.e., 99.48%, 92.22%, 88.10/78.5%, and 30.0%, respectively. OFS-L removed more Cd (II) than OFS-B during the modification. OFS-L now improves the bioavailability and accumulation of Cd (II) in the plant (18.5 µg/g) and has a higher chlorophyll-b concentration (1.92 mg/g fresh weight) than other systems. The wettable clay exhibited clay leaching into the various levels of the bioretention system. In the bioretention system, benzyl substituted clay prevented the penetration of water and formed a Cd (II) agglomeration. When compared to non-wettable modifiers, these results indicated that wettable clay material could be a capable material for removing Cd (II). [ABSTRACT FROM AUTHOR]

In this study, a high-efficiency magnetic heavy metal flocculant MF@AA was prepared based on carboxymethyl chitosan and magnetic Fe3O4. It was characterized by SEM, FTIR, XPS, XRD and VSM, and the Cu(II) removal rate was used as the evaluation basis for the preparation process. The effects of AMPS content, total monomer concentration, photoinitiator concentration and reaction time on the performance of MF@AA flocculation to remove Cu(II) were studied. The characterization results show that MF@AA has been successfully prepared and exhibits good magnetic induction characteristics. The synthesis results show that under the conditions of 10% AMPS content, 35% total monomer concentration, 0.04% photoinitiator concentration, and 1.5 h reaction time, the best yield of MF@AA is 77.69%. The best removal rate is 87.65%. In addition, the response surface optimization of the synthesis process of MF@AA was performed. The optimal synthesis ratio was finally determined as iron content 6.5%, CMFS: 29.5%, AM: 53.9%, AMPS: 10.1%. High-efficiency magnetic heavy metal flocculant MF@AA shows excellent flocculation performance in removing Cu(II). This research provides guidance and ideas for the development of efficient and low-cost flocculation technology to remove Cu(II) in wastewater. [ABSTRACT FROM AUTHOR]

In this experiment, a variety of inorganic materials were simply compounded with Polysilicate Aluminum Ferric Sulfate (PSAFS) to treat emulsified oil-contaminated water. Manganese sulfate (MnSO4), magnesium sulfate (MgSO4), and zinc sulfate (ZnSO4) were selected as the materials to modify PSAFS in order to obtain a coagulant with good flocculation performance. During the preparation of modified PSAFS, metal manganese, magnesium, and zinc were introduced for modification, and four factors were used to optimize the best proportion of modifiers and PSAFS. The results showed that the order of demulsification and oil-removal ability is as follows: Mn-PSAFS (Mn-modified PSAFS) > Zn-PSAFS (Zn-modified PSAFS) > Mg-PSAFS (Mg-modified PSAFS) > PSAFS. Modified PSAFS was characterized by infrared spectroscopy (IR) and a Scanning Electron Microscope (SEM). In the range of 604 cm−1 to 1200 cm−1, due to the complexation reaction between metal ions and polysilicic acid, the absorption peaks of the modified PSAFS and PSAFS were significantly different. SEM results revealed that the particles of the spatial network structure were fibrous and arranged more closely (0.5 mm × 50.0 mm) than others. This study provided that the modified PSAFS had good potential application in treating emulsified oily wastewater in the future. [ABSTRACT FROM AUTHOR]