Enhanced photocatalytic degradation of dimethyl phthalate by magnetic dual Z-scheme iron oxide/mpg-C3N4/BiOBr/polythiophene heterostructure photocatalyst under visible light

Enhanced sonophotocatalytic degradation of phthalate acid ester using copper-chromium layered double hydroxides on carbon nanotubes and biochar

Layered double hydroxides (LDHs) are lamellar and stable nanocatalysts driven by visible light. They have received much attention in the context of advanced oxidation processes. Their catalytic performance is remarkably restricted owing to undesired aggregation and the possibility of electron-hole recombination. To address these issues, we engineered carbon-nanotube (CNT)-and biochar (BC)-based CuCr LDH nanocomposites via a facile hydrothermal method. The synthesized nanocomposites were physically and chemically characterized using various methods. The performances of the BC-CuCr LDH and CNT-CuCr LDH nanocomposites were compared during the sonophotocatalytic degradation of dimethyl phthalate. With 1.5 g L-1 of BC-CuCr LDH, complete degradation of dimethyl phthalate was achieved within 25 min under 50 W light intensity and 150 W ultrasound irradiation with a synergy factor of 14. The critical roles of the hydroxyl and superoxide radicals were confirmed by the addition of several inhibitors. Ultimately, six possible intermediates generated during the sonophotocatalytic process were identified using gas chromatography-mass spectrometry (GCMS).

Recent advances on photocatalytic degradation of phthalate ester plasticizers using nanomaterial photocatalysts

Phthalate esters (PAEs) are a class of organic ester compounds containing benzene rings, which have been widely applied as additives in various fields, especially as plasticizers in plastic product to improve the flexibility. Due to the non-covalent bonding, PAEs inevitably leach out from the plastic polymers into environments. PAEs are endocrine disruptors, which possess seriously hazards to organisms, such as reproductive and genetic abnormalities. Now, PAEs pollution has become a serious environmental problem. Moreover, due to its difficulty in natural degradation, it has become a widespread concern to eliminate PAEs pollution with energy-saving technology. Among various degradation technologies for organic pollutant removal, photocatalytic degradation has attracted more attentions due to the merits of low energy consumption, high removal efficiency, abundant photocatalyst and low secondary pollution. In this article, the photocatalytic degradation using nanomaterial photocatalysts towards four kinds of typical PAEs were reviewed, including di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), dimethyl phthalate (DMP), and diethyl phthalate (DEP). To improve the photocatalytic degradation efficiency, various semiconductor photocatalysts have been developed, and the optical and electrochemical properties, and the degradation mechanism and pathway have been also discussed. Finally, the challenges and perspectives of photocatalytic technology on PAEs elimination were presented.

A critical review of recent advancements in the photocatalysis process, mechanism, and degradation pathways for the removal of phthalates from the contaminated water matrix

Phthalates, a sort of plasticizer, are widely utilized in various consumer products and pose significant environmental and health risks due to their persistence and potential toxicity. This review explores the occurrence, sources, environmental impact, and remediation strategies for phthalates. Various remediation techniques have been investigated to address phthalate contamination. Among these, photocatalysis, an advanced oxidation process (AOP), has emerged as a viable approach due to its ability to mineralize organic contaminants into innocuous byproducts. The review discusses the recent advancements in photocatalytic processes, the underlying mechanisms, and degradation pathways for phthalate removal. The mechanism of photocatalytic degradation includes the generation of reactive oxygen species like hydroxyl radicals (OH•) and superoxide radicals (O2-•) and their role in breaking down phthalate molecules. It also highlights recent advancements in photocatalytic materials, such as metal-doped semiconductors and composite materials, which enhance the removal efficiency. The review concludes by emphasizing the need for integrated approaches to achieve effective and sustainable phthalate remediation. Future research should focus on developing efficient and cost-effective photocatalytic materials, optimizing reactor design, and scaling up photocatalytic processes for practical applications. The review also highlights the challenges and limitations of photocatalytic processes, including low quantum efficiency, catalyst deactivation, and mass transfer limitations. Potential areas of study are put forward to address these challenges and further advance the application of photocatalysis for phthalate removal. This review intends to help the development of efficient photocatalytic technologies for the remediation of phthalate-contaminated water by providing a complete overview of the present state of the art.

Ultrasonic-assisted photocatalytic degradation of various organic contaminants using ZnO supported on a natural polymer of sporopollenin

Water resource pollution by organic contaminants is an environmental issue of increasing concern. Here, sporopollenin/zinc oxide (SP/ZnO) was used as an environmentally friendly and durable catalyst for sonophotocatalytic treatment of three organic compounds: direct blue 25 (DB 25), levofloxacin (LEV), and dimethylphtalate (DMPh). The resulting catalyst had a 2.65 eV bandgap value and 9.81 m²/g surface area. The crystalline structure and functional groups of SP/ZnO were confirmed by X-ray diffraction (XRD) and Fourier transforms infrared spectroscopy (FTIR) analyses. After 120 min of the sonophotocatalysis, the degradation efficiencies of DB 25, LEV, and DMPh by SP/ZnO were 86.41, 75.88, and 62.54%, respectively, which were higher than that of the other investigated processes. The role of reactive oxygen species were investigated using various scavengers, enhancers, photoluminescence, and o-phenylenediamine. Owing to its stability, the catalyst exhibited good reusability after four consecutive cycles. In addition, the high integrity of the catalyst was confirmed by scanning electron microscopy (SEM), XRD, and FTIR analyses. After four consecutive examinations, the leaching of zinc in the aqueous phase was < 3 mg/L. Moreover, gas chromatography-mass spectrometry (GC-MS) analyses indicated that the contaminants were initially converted into cyclic compounds and then into aliphatic compounds, including carboxylic acids and animated products. Thus, this study synthesized an environmentally friendly and reusable SP/ZnO composite for the degradation of various organic pollutants using a sonophotocatalytic process.

Application of ComplexGAPI for the green assessment of a deep eutectic solvent-based ferrofluid assisted liquid-liquid microextraction method for detection of dimethyl phthalate in beverage samples

In the present study, a novel ferrofluid was prepared by combining a menthol/thymol deep eutectic solvent with magnetic nanoparticles (Fe₃O₄@OA). This composite was first applied in vortex-assisted liquid-liquid microextraction (VA-LLME), followed by high performance liquid chromatography with ultraviolet detection (HPLC-UV) for the determination of dimethyl phthalate (DMP) residues in beverages. The synthesized deep eutectic solvent-based ferrofluid (DES-FF) was characterized by using Fourier transform infrared spectrometry (FTIR), vibrating sample magnetometry (VSM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Furthermore, the type of carrier, pH of the sample solution, ferrofluid volume, salt amount, vortex time, type and volume of elution solvents and desorption time were statistically optimized for high extraction efficiencies. Under the optimal extraction conditions, the limit of detection (LOD) and limit of quantification (LOQ) were 0.008 μg mL^-1 and 0.03 μg mL^-1, respectively. Moreover, the mean recoveries for DMP ranged from 85.2% to 99.5%, and intra- and inter-day precisions were less than 5.5% and 7.8%, respectively. The proposed method was successfully applied to the analysis of dimethyl phthalate in real samples, making it a promising analysis technique for beverage samples. The greenness of the entire procedure of our proposed method was assessed by comparing it with other reported methods using ComplexGAPI (Complex Green Analytical Procedure Index). The results show that our proposed method has a better greenness than other reported methods.

A novel simultaneous coupling of memory photocatalysts and microbial communities for alternate removal of dimethyl phthalate and nitrate in water under light/dark cycles

Efficient and sustainable removal of both organic and inorganic pollutants from contaminated water is an important but difficult task. Here, a novel chemical-biological coupling concept, namely simultaneous coupling of memory photocatalysts and microbial communities (SCMPMC), is proposed for the first time that alternates the removal of organic and inorganic pollutants under successive light/dark cycles. We established this novel coupling system with WO₃/g-C₃N₄ memory photocatalysts and river sediment microbial communities, and applied it to alternately remove dimethyl phthalate (DMP) and nitrate under light/dark cycles. The performance of SCMPMC under the light/dark cycles (12/12 h) showed that ~84.90% of the DMP was removed mainly via robust photocatalytic oxidation during the light phase, and ~86.80% of the nitrate was removed via microbial reduction enhanced by photogenerated electrons stored in the WO₃/g-C₃N₄ memory photocatalysts during the dark phase within one cycle. The microbial communities were positively affected by adding WO₃/g-C₃N₄, as evidenced by increased enzyme activities, cellular antigen metabolism, and relative abundance of typical denitrifiers, including Proteobacteria and Bacteroidetes. These results will contribute to the development of promising decontamination methods and mechanisms to control water pollution driven by the natural day/night cycle.

Recent Advances in Endocrine Disrupting Compounds Degradation through Metal Oxide-Based Nanomaterials

Endocrine Disrupting Compounds (EDCs) comprise a class of natural or synthetic molecules and groups of substances which are considered as emerging contaminants due to their toxicity and danger for the ecosystems, including human health. Nowadays, the presence of EDCs in water and wastewater has become a global problem, which is challenging the scientific community to address the development and application of effective strategies for their removal from the environment. Particularly, catalytic and photocatalytic degradation processes employing nanostructured materials based on metal oxides, mainly acting through the generation of reactive oxygen species, are widely explored to eradicate EDCs from water. In this review, we report the recent advances described by the major publications in recent years and focused on the degradation processes of several classes of EDCs, such as plastic components and additives, agricultural chemicals, pharmaceuticals, and personal care products, which were realized by using novel metal oxide-based nanomaterials. A variety of doped, hybrid, composite and heterostructured semiconductors were reported, whose performances are influenced by their chemical, structural as well as morphological features. Along with photocatalysis, alternative heterogeneous advanced oxidation processes are in development, and their combination may be a promising way toward industrial scale application.