Treatment Of Organic Pollutants Research Articles

Recent Advances in Piezocatalysts for Dye Degradation

AbstractPiezocatalysis is attracting extensive attention in recent years because it can directly convert mechanical energy from the ambient environment (such as tiny vibrations and noise) into piezopotential for catalytic activities. Dyes are widely used in diverse industries, including paper, printing, and textiles, which cause serious environmental problems due to their persistence and toxicity. Unlike traditional catalysts that rely on chemical reactions to drive dye degradation, piezocatalysts offer a sustainable and cost‐effective alternative to breaking down complex molecules through creating highly reactive species, which have shown a significant promise in the treatment of organic pollutants in wastewater. In this review, the basic principles of piezocatalysis are first outlined, specifically describing two ubiquitous forms of driving force in nature. Following the catalytic mechanism, the current mainstream piezocatalytic materials are classified into two categories: organic and inorganic materials with detailed discussions. Moreover, after investigating and analyzing previous literature, effective strategies for improving piezocatalytic efficiency for dye degradation are systematically compared and summarized. In the end, current issues that need to be addressed in the future as well as potential research directions related to piezocatalysis are prospected. This work provides an insight into solving current issues to advance the piezocatalysts.

Recent advances on the treatment of oilfield-produced water by advanced oxidation processes: A review

ABSTRACT Despite the advancements in alternative fuels and energy sources, there continues to be a significant global dependence on oil production and extraction. A substantial volume of oilfield-produced water (OPW) is generated during the production and extraction processes of oil fields. Recurrent OPW treatments encountered significant challenges in addressing this particular type of wastewater. Advanced oxidation processes (AOPs) are regarded as a promising alternative approach for the degradation of recalcitrant organic compounds in the OPW. This review focuses on the characterization of OPW. The treatment of organic pollutants in wastewater using AOPs, such as ozonation, Fenton oxidation-based processes, heterogeneous photocatalysis, and persulfate oxidation, is comprehensively reviewed in terms of their efficiency for pollutant degradation. The primary challenges in this field and the future directions for development are proposed, with the aim of providing a valuable reference for achieving highly effective treatment of OPW.

Graphene Oxide Treated by Temperature with Enhancement of Adsorption for Organic Pollutants and Catalytic Degradation with Hydrogen Peroxide

Graphene oxide (GO) has been used in the range of organic pollutants adsorption and degradation. It’s important to improve the performance of GO in the treatment of organic pollutants. Here, we found that the organic pollutants were more efficiently removed in the catalytic degradation of hydrogen peroxide (H2O2) after being pre-adsorbed with GO. The performance of GO in degrading organic pollutants firstly enhanced and then weakened as the treated temperature increases in the air. The adsorption ability of GO for organic pollutants and catalytic activity of H2O2 were highest at 500 ℃, which can be ascribed to the highest oxygen-containing functional groups and the lowest defects on GO after 500 ℃ treatment in the air. This finding will improve the understanding and application of GO in organic pollutants treatment.Graphical

Functionalized Cellulose for Textile Organic Pollutant Treatment: a Comprehensive Review

Functionalized Cellulose for Textile Organic Pollutant Treatment: a Comprehensive Review

Progress of organic wastewater degradation by atmospheric pressure gliding arc plasma technology: A review

The prevention and treatment of organic pollutants in wastewater have attracted extensive attention because they threaten ecological balance and human health. Traditional wastewater treatment technologies, such as physical, chemical, biological methods, etc., are still limiting and challenging due to some factors, such as high energy consumption, chemical agents, low efficiency, and secondary pollution. At present, gliding arc plasma, based on equilibrium/non-equilibrium in plasma temperature, demonstrates itself to be one of the most promising technologies for the degradation of refractory organics with its fast degradation rates, no secondary contamination, high efficiency, and so on. The theoretical mechanisms and typical applications of gliding arc plasma degradation of wastewater are introduced in detail in this paper. The physical and chemical characteristics of gliding arc plasma and the role of the reactive species in the plasma are reviewed.

Design of low-cost natural casein biopolymer based adsorbent for efficient adsorption of multiple anionic dyes and diclofenac sodium from aqueous solutions

The treatment of various organic pollutants from industrial wastewater using bio-based materials has gained significant attention owing to their excellent properties such as low-cost, eco-friendly, non-toxic, and biodegradability. In this perspective, casein (Cn), a protein-based biopolymer, was extracted from the cow milk as a low-cost adsorbent, and the adsorption performances were determined for the pristine Cn. The adsorbent was employed for the removal of two different classes of targeted pollutant anionic dyes such as Congo red (CR), Eriochrome Black T (EBT), Eosin Y (EY), and pharmaceutical waste i.e., diclofenac sodium (DS) and displayed better adsorption performances with the maximum adsorption capacity of 85.54, 31.72, 70.42 and 358.42 mg g-1 respectively. The interactions between Cn and pollutants are mainly ascribed to the electrostatic interaction, hydrogen bonding, hydrophobic interaction, and π-π interactions. Furthermore, to validate with realistic application the adsorbent proved with an excellent removal efficiency of 91.43% for fabric whitener i.e., Ujala Supreme®. These obtained results suggest that the Cn could be the potential adsorbent to effectively eliminate toxic pollutants from the aqueous solutions.

Temperature-responsive comprehensive two-dimensional liquid chromatography coupled to high resolution mass spectrometry for the elucidation of the oxidative degradation processes of chemicals of environmental concern

This study explores the possibilities offered by temperature-responsive liquid chromatography (TRLC) based comprehensive 2-dimensional liquid chromatography in combination with reversed-phase liquid chromatography (RPLC) for the analysis of degradation products formed upon oxidative treatment of persistent organic pollutants, in this case exemplified through carbamazepine (CBZ). The TRLC×RPLC combination offers the possibility to overcome peak overlap and incomplete separation encountered in 1D approaches, while the transfer of the purely aqueous mobile phase leads to refocusing of all analytes on the second dimension column. Consequently, this allows for about method-development free and hence, easier LC×LC. The study focuses on the oxidative degradation of CBZ, a compound of environmental concern due to its persistence in water bodies. The TRLC×RPLC combination effectively separates and identifies CBZ and its degradation products, while offering improved selectivity over the individual TRLC or RPLC separations. This allows gathering more understanding of the degradation cascade and allows real-time monitoring of the appearance and disappearance of various degradation products. The compatibility with high-resolution mass spectrometry is last shown, enabling identification of 21 CBZ-related products, nine of which were not previously reported in CBZ degradation studies. The approach's simplicity, optimization-free aspects, and ease of use make it a promising tool for the analysis of degradation pathways in environmental contaminants.

Improved photocatalytic oxidation of micropollutant in wastewater by solar light: assisted palladium-doped graphitic carbon nitride.

Theescalating global industrial expansion has led to the extensive release of organic compounds into water bodies, resulting in substantial pollution and posing severe threats to both human health and the ecosystem. Among common micropollutants, bisphenol A (MP-BA)has emerged as a significant endocrine-disrupting chemical with potential adverse effects on human health and the environment. This study aims to develop an efficient photocatalyst, specifically by incorporating palladium-doped graphitic carbon nitride (Pd@GCN), to eliminate MP-BA pollutants present in industrial wastewater. The examination of optical properties and photoluminescence indicates that incorporating Pd into GCN enhances the visible light absorption spectra, which extends beyond 570nm, and accelerates the separation rate of electron-hole pairs. The photocatalytic degradation efficiency of MP-BA increases from 81.7 to 98.8% as the solution pH rises from 5.0 to 9.0. Moreover, Pd@GCN significantly improves the removal rate of MP-BA in wastewater samples, reaching an impressive 92.8% after 60min of exposure to solar light. Furthermore, the Pd@GCN photocatalyst exhibits notable reusability over six cycles of MP-BA degradation, indicating its promising potential for the treatment of organic pollutants in wastewater under solar light conditions.

A Review on Various Bio-Resources as a Tool to Reduce Water Pollution Via Eco-Friendly Adsorption Technology

Pollution of water bodies is a raising concern in today’s world. Water pollution occurs when harmful compounds enter water bodies and lowers the water quality. It is necessary to treat wastewater before its final disposal into aquatic bodies and environment. Among all the conventional water treatment techniques, adsorption technology attracted much attention owing to its simplicity and eco-friendly nature. Several studies were reported with the application of different kinds of adsorbents in the treatment of both organic and inorganic pollutants in wastewater. However, demand for the development of more suitable adsorbent with selective pollutant removal capacity and good economic feasibility is still rising. Therefore, this review aims to provide a detailed review about the adsorption technology and its mechanisms in pollutant removal process. The adsorption ability of certain important adsorbents were discussed along with future perspectives. Effective, economical, and environmentally friendly wastewater management should be the ultimate objective of any wastewater treatment process. Keeping that in view, this review article highlighted the importance of wastewater management and treatment via adsorption technology.

Facile Synthesis of a Novel AgIO3/CTF Heterojunction and Its Adsorption-Photocatalytic Performance with Organic Pollutants.

With the development of modern industry, the issue of water pollution has garnered increasing attention. Photocatalysis, as a novel green environmental technology that is resource-efficient, environmentally friendly, and highly promising, has found extensive applications in the field of organic pollutant treatment. However, common semiconductor materials exhibit either a relatively low photocatalytic efficiency in the visible light range or an inefficient separation of photogenerated charges, resulting in their limited ability to harness solar energy effectively. Consequently, the development of new photocatalysts has become a pivotal focus in current photocatalysis research to enhance solar energy utilization. This research provides a brief explanation of the photocatalytic mechanism of the AgIO3/CTF heterojunction photocatalyst. Due to the localized surface plasmon resonance (LSPR) effect, the Ag nanoparticles demonstrate significant absorption in the visible light region, playing a crucial role in the highly efficient photocatalytic reduction of organic pollutants.

Activation of peroxymonosulfate by a CuCo-NC diatomic catalyst on N-doped graphene for selective generation of 1O2 towards efficient organic pollutant treatment

Singlet oxygen (1O2) is an excellent active species for the selective degradation of organic pollutants. However, it is difficult to achieve efficiently and highly selective 1O2 generation. Herein, we report a Cu-doped Co-rGO (CuCo-rGO) as a precursor to construct diatomic catalyst (CuCo-NC) with both single atomic (SA) Co and Cu sites. The CuCo-NC activated peroxymonosulfate (PMS) can generate singlet oxygen (1O2) with high efficiency, which shows efficient degradation of tetracycline (TC) under wide pH rage and ubiquitous anions (H2PO4-, HCO3-, NO3-, Cl-) conditions. Meanwhile, CuCo-NC/PMS system can nearly 100% degrade the persistent organic pollutant (atrazine). Compared with SA Cu and SA Co sites, density functional theory calculations (DFT) demonstrate that the Cu-doping can improve the Co 3d orbital bonding distribution and reduce the adsorption energy of PMS. The role and formation mechanism of 1O2 are also analyzed and discussed. This work reveals the synergistic mechanism of the CuCo diatomic active sites for selective activation of PMS and provides a new direction for the development of novel catalyst with production of 1O2.

Novel Cerium (IV) Oxide -Ti3C2- titanium dioxide heterostructure photocatalyst for pharmaceutical pollutants removal: Photocatalyst characterization, process optimization and transformation pathways

Tetracycline (TC) is a widely applied antibiotic recognized for its potential negative consequences on human health and ecological balance. In this study, a novel photocatalyst, Cerium (IV) oxide -Ti3C2- titanium dioxide (CeMXT), was synthesized through sonochemical and impregnation techniques, subsequently subjected to comprehensive characterization employing diverse methods including XRD, SEM, TEM, HR-TEM, Raman, XPS, and BET. The optimization of TC degradation was pursued using the Response Surface Methodology (RSM), encompassing variables such as initial TC concentration, irradiation duration, photocatalyst dosage, and pH. The degradation efficacy was investigated through free radical trapping experiments, revealing the pivotal roles of OH and superoxide anion radicals. Remarkable degradation efficiency, reaching 94.70 %, was achieved under specific parameter conditions: 22.19 mg/L TC concentration, 104.13 min irradiation, 0.65 g/L photocatalyst dosage, and pH 4.72. This exceptional performance could be attributed to the elevated generation of oxidant species facilitated by the Z-scheme electron transfer heterojunction. Furthermore, LC-Mass analysis was employed to delineate the intermediates formed during TC photodegradation, culminating in proposing a conceivable degradation pathway. The impressive proficiency of the CeMXT photocatalyst underscores its potential application for effective large-scale treatment of persistent organic pollutants in wastewater treatment facilities. Additionally, comparative analysis with a recently developed photocatalyst highlights its promise as a viable alternative for the remediation of such contaminants in aquatic ecosystems.

Double pyramid stacked CoO nano-crystals induced by graphene at low temperatures as highly efficient Fenton-like catalysts.

Transition metal oxides are widely used as Fenton-like catalysts in the treatment of organic pollutants, but their synthesis usually requires a high temperature. Herein, an all-solid-state synthesis method controlled by graphene was used to prepare a double pyramid stacked CoO nano-crystal at a low temperature. The preparation temperature decreased by 200 °C (over 30% reduction) due to the introduction of graphene, largely reducing the reaction energy barrier. Interestingly, the corresponding degradation rate constants (kobs) of this graphene-supported pyramid CoO nano-crystals for organic molecules after their adsorption were over 2.5 and 35 times higher than that before adsorption and that of free CoO, respectively. This high catalytic efficiency is attributed to the adsorption of pollutants at the surface by supporting graphene layers, while free radicals activated by CoO can directly and rapidly contact and degrade them. These findings provide a new strategy to prepare low carbon-consuming transition metal oxides for highly efficient Fenton-like catalysts.

Hierarchical zeolite-encapsulated metal nanoparticles for heterogeneous catalysis.

Zeolites, characterized by their highly porous structure, have become integral to modern industry and environmental science due to their broad applications in adsorption, separation, and catalysis. Recent advancements in zeolite synthesis, particularly through hydrothermal methods and the incorporation of metal nanoparticles, have significantly expanded their utility. This review delves into the innovative strategies for encapsulating metal nanoparticles within zeolite matrices, enhancing catalytic reactions' efficiency, selectivity, and durability. Challenges such as nanoparticle agglomeration and catalyst deactivation are addressed through hierarchical zeolite encapsulation, which provides a novel route for the development of multifunctional materials. By examining methods ranging from in situ encapsulation to post-synthetic recrystallization, this review highlights the versatility and potential of metal@zeolite catalysts in various applications, including organic synthesis, pollutant treatment, and energy conversion. The review underscores the importance of optimizing the interaction between metal nanoparticles and the zeolite framework to achieve superior catalytic performance, offering new directions for research in catalytic science and industrial process optimization.

Peroxymonosulfate activation by CuMn-LDH for the degradation of bisphenol A: Effect, mechanism, and pathway

The remediation of water contaminated with bisphenol A (BPA) has gained significant attention. In this study, a hydrothermal composite activator of Cu3Mn-LDH containing coexisting phases of cupric nitrate (Cu(NO3)2) and manganous nitrate (Mn(NO3)2) was synthesized. Advanced oxidation processes were employed as an effective approach for BPA degradation, utilizing Cu3Mn-LDH as the catalyst to activate peroxymonosulfate (PMS). The synthesis of the Cu3Mn-LDH material was characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). According to the characterization data and screening experiments, Cu3Mn-LDH was selected as the best experimental material. Cu3Mn-LDH exhibits remarkable catalytic ability with PMS, demonstrating good degradation efficiency of BPA under neutral and alkaline conditions. With a PMS dosage of 0.25 g·L−1 and Cu3Mn-LDH dosage of 0.10 g·L−1, 10 mg·L−1 BPA (approximately 17.5 μM) can be completely degraded within 40 min, of which the TOC removal reached 95%. The reactive oxygen species present in the reaction system were analyzed by quenching experiments and EPR. Results showed that sulfate free radicals (SO4•—), hydroxyl free radicals (•OH), superoxide free radicals (•O2—), and nonfree radical mono-oxygen were generated, while mono-oxygen played a key role in degrading BPA. Cu3Mn-LDH exhibits excellent reproducibility, as it can still completely degrade BPA even after four consecutive cycles. The degradation intermediates of BPA were detected by GCMS, and the possible degradation pathways were reasonably predicted. This experiment proposes a nonradical degradation mechanism for BPA and analyzes the degradation pathways. It provides a new perspective for the treatment of organic pollutants in water.

A new perspective for surface modifying TiO2 to effectively enhance its visible light photocatalytic activity

In this study, a new perspective was proposed to regulate the photocatalytic properties of TiO2 and a novel TiO2-based composite (BA@TiO2) with nitrogen-containing surface layer was obtained by surface modifying TiO2 with an organic molecular (3,3′-Diaminobenzidine, BA). The composite (BA@TiO2) exhibited high responsiveness to visible light and great photocatalytic activity, which could remove 92% of tetracycline hydrochloride (TC), and also maintained a high ability to photodegrade low concentrations of TC. The free radical trapping experiments showed that h+ and •O2- were the most dominant active species in the degradation process. The possible degradation pathways of TC were deduced with the help of HPLC-MS and fuikui index. QSAR was used to perform toxicity analysis of the degradation intermediates. In addition, the composites demonstrated good recyclable stability and removal efficiency of TC in real water samples, indicating BA@TiO2 is a purifying agent with great efficiency and sustainability for practical treatment of organic pollutants in aqueous media.

Surface plasmon resonance effect of silver decorated on BiOCl and its enhanced sunlight-active photodegradation of rhodamine B (RhB) dye and ofloxacin (OFL) antibiotic

Fast electron-hole recombination rate is the major problem concerning low photocatalytic performance of the UV-active BiOCl photocatalyst. To overcome this drawback, decoration of noble metals on the surface of semiconducting photocatalysts can be regarded as one of the promising strategies to improve the photoactivity due to a synergy of heterojunction formation and surface plasmon resonance effect. However, the huge dosage (larger than 10 wt%) of the noble metal incorporated on photocatalyst surface causes high cost in production of the final product. In this work, solvothermally grown BiOCl photocatalyst was decorated with low silver metal loading of 2.5–10 wt%. The tetragonal 2.5 wt%Ag/BiOCl photocatalyst exhibited complete photodegradation of Rhodamin B (RhB) dye and ofloxacin (OFL) antibiotic under natural solar light. The enhancement of the resultant photocatalytic efficiency is possibly due to increasing of charge carrier separation efficiency at the interface together with the formation of the Schottky barrier at the Ag/BiOCl interface so that an improvement in quantum efficiency and an increase in the photocatalytic activity are expected. In addition, well dispersion of silver on BiOCl also leads to red shift in the absorption of light toward visible regime. This is due to the local surface plasmon resonance (LSPR) effect of Ag on BiOCl surface. The synthesized Ag/BiOCl photocatalyst displays enhanced photocatalytic activity with great structural stability after five times of use indicating its excellent cycling ability. The present finding offers a new pathway to create a silver decorated BiOCl for complete removal of harmful dye and antibiotic in aqueous solution. The treatment of toxic organic pollutants in the natural water can be done very easily by utilization of the green technology based on photocatalytic method with the beneficial of abundant solar energy.

Efficient adsorption and photocatalysis over a photorenewable uranyl-organic framework for removal of diquat herbicide

Adsorption and photocatalysis are generally considered an environmental friendliness and effective methods for eliminating organic pollutants. Developing bifunctional materials that integrate adsorption and photocatalysis can fully leverage the adsorption effect to increase the interaction between herbicides and photocatalysts, thus improving their photocatalytic degradation efficiency. To achieve the absorption and photocatalytic activity on contaminants, a light-sensitive three-dimensional uranyl-organic framework (UOF) named HNU-80 with an anionic skeleton was synthesized in this work. The charge characteristics of its electrostatic attraction with cations and the suitable band structure for producing reactive oxygen endow it with the potential for efficient adsorption and photocatalytic oxidation of the cationic diquat herbicide. The maximum adsorption capacity is up to 97.92 mg·g−1, and the adsorbed diquat could be completely degraded under light irradiation. In addition, the regenerated HNU-80 exhibits high reusability in subsequent adsorption cycle experiments. The adsorption mechanism is attributed to the electrostatic and π…π interaction between HNU-80 and diquat, while the photodegradation mechanism is due to the oxidation and decomposition of diquat by reactive oxygen species generated from the radiation of HNU-80. This work provides a promising candidate for the harmless treatment of organic pollutants, and the combination of photocatalytic property also promotes the regeneration of the UOF adsorbents for continued use.

Review of the recent advances on the fabrication, modification and application of electrospun TiO2 and ZnO nanofibers for the treatment of organic pollutants in wastewater

The heightened occurrence of emerging organic pollutants (EOPs) in aquatic bodies has been the subject of global apprehension due to the toxicity they pose to the environment, humans and animals alike. The presence of EOPs has soared due to industrialization and is further exacerbated by human activities like the overuse and poor disposal of dyes, pesticides, pharmaceuticals, surfactants, personal care products and food additives. The complete treatment and removal of EOPs from industrial wastewater and sewage has remained a challenge because of their pseudo-persistence and resistance to degradation. Due to their impressive light absorption properties, high surface-area-to-volume ratio, high porosity, superior mechanical strength, electrospun titanium dioxide (TiO2) and zinc oxide (ZnO) nanofibers have been proposed for the photocatalytic treatment of EOPs. Therefore, this review first highlights the fabrication and modification methods of TiO2 and ZnO nanofibers. A systematic survey of the latest progress in the application of TiO2 and ZnO nanofibers for the degradation of EOPs is then elaborated. Thus, the main goal is to shed light and give insight to researchers on the possibilities surrounding the elimination of EOPs by applying electrospun TiO2 and ZnO semiconductor materials. In addition, the loopholes associated with fabrication and modification processes are discussed with the aim of encouraging innovation for prospective technology advancement and commercialization, as well as to enhance research efforts in wastewater treatment and environmental sustainability.

Magnetic perovskite nanohybrid based on g-C3N4 nanosheets for photodegradation of toxic environmental pollutants under short-time visible irradiation

In this study, a magnetic perovskite nanohybrid based on g-C3N4 (gCN) nanosheets was synthesized and developed for the efficient photodegradation of toxic environmental pollutants under short-time visible irradiation. The synthesis of this nanohybrid involved the incorporation of SrTiO3:N (STO:N) and ZnFe2O4 (ZnF) onto the g-C3N4 nanosheets through a simple reflux method. Our investigation encompassed a comprehensive suite of analytical techniques, including BET, TGA, TEM, SEM, EDX, DRS, VSM, XRD, photocurrent, and FT-IR, to elucidate the physicochemical characteristics of this nanocomposite in the context of its application in photodegradation processes. The nanohybrid displayed significantly enhanced photocatalytic activity compared to its individual components, achieving a degradation efficiency of over 90% for various pollutants, including organic dyes like Rhodamine B (Rh-B), within a short irradiation time. This enhanced activity can be attributed to the synergistic effect between gCN, STO:N, and ZnF, which promotes the generation of reactive oxygen species and facilitates the degradation process. Notably, the nanocomposite containing 20 wt% STO:N perovskite and 20 wt% ZnF demonstrated the highest Rh-B degradation rate under visible light irradiation within just 30 min. Furthermore, the nanohybrid displayed excellent stability and reusability over seven consecutive runs, retaining its high photocatalytic activity even after multiple cycles of degradation. This remarkable performance can be attributed to the strong interaction between the gCN nanosheets and the magnetic perovskite components, which prevents their aggregation and ensures their efficient utilization. Additionally, the nanohybrid exhibited excellent visible light absorption, enabling the utilization of a wider range of light for degradation. This feature is particularly advantageous, as visible light is more abundant in sunlight compared to UV light, rendering the nanohybrid suitable for practical applications under natural sunlight. In conclusion, the ternary gCN-STO:N@ZnF nanocomposite represents a promising candidate for the treatment of organic pollutants in aqueous environments, offering a versatile and efficient solution.