Environmental Remediation Applications Research Articles

Photocatalytic Degradation of Lignin using TiO2 from Ilmenite Prepared by Microwave Method

This study investigates the photocatalytic degradation of lignin using TiO2 extracted from ilmenite through a microwave-assisted method. Characterization of the iron sand, which serves as the source of ilmenite, was conducted using X-ray fluorescence spectroscopy (XRF) and Energy Dispersive X-ray Spectroscopy (EDX). The XRF analysis revealed that the iron sand primarily consists of Fe and TiO2, with minor impurities such as Al2O3, MgO, and SiO2. After extraction, the iron mineral content increased significantly, while impurities decreased. EDX analysis confirmed the presence of Fe, O, and Ti elements in the iron sand sample, originating from various iron oxide phases. Subsequent degradation tests on lignin with varying microwave heating durations of ilmenite showed that a 90-minute heating duration achieved the highest lignin degradation percentage of 56.69%. This suggests that the optimum heating time for ilmenite is crucial for maximizing its photocatalytic activity. Overall, the findings highlight the potential of microwave-prepared TiO2 from ilmenite for efficient lignin degradation, with implications for environmental remediation and industrial applications.

Sn(IV)porphyrin-Incorporated TiO2 Nanotubes for Visible Light-Active Photocatalysis.

In this study, two distinct photocatalysts, namely tin(IV)porphyrin-sensitized titanium dioxide nanotubes (SnP-TNTs) and titanium dioxide nanofibers (TNFs), were synthesized and characterized using various spectroscopic techniques. SnP-TNTs were formed through the hydrothermal reaction of NaOH with TiO2 (P-25) nanospheres in the presence of Sn(IV)porphyrin (SnP), resulting in a transformation into Sn(IV)porphyrin-imbedded nanotubes. In contrast, under similar reaction conditions but in the absence of SnP, TiO2 (P-25) nanospheres evolved into nanofibers (TNFs). Comparative analysis revealed that SnP-TNTs exhibited a remarkable enhancement in the visible light photodegradation of model pollutants compared to SnP, TiO2 (P-25), or TNFs. The superior photodegradation activity of SnP-TNTs was primarily attributed to synergistic effects between TiO2 (P-25) and SnP, leading to altered conformational frameworks, increased surface area, enhanced thermo-chemical stability, unique morphology, and outstanding visible light photodegradation of cationic methylene blue dye (MB dye). With a rapid removal rate of 95% within 100 min (rate constant = 0.0277 min-1), SnP-TNTs demonstrated excellent dye degradation capacity, high reusability, and low catalyst loading, positioning them as more efficient than conventional catalysts. This report introduces a novel direction for porphyrin-incorporated catalytic systems, holding significance for future applications in environmental remediation.

Trends on barrier characteristics improvement of emerging biopolymeric composite films using nanoparticles - A review

BackgroundBio-based films have wide applications in various areas, including medical, packaging, biosensor design, and environmental remediation. Unfortunately, their associated features restricted the application windows for these bio-based films. Barrier properties, such as H2O permeability, O2 permeability, and UV-barrier properties, are among the typical qualities important in designing packaging films because they safeguard food safety and extend shelf life. MethodsEnhancing the barrier qualities has been imperative in recent years owing to its significant impact on food preservation and the valorization of natural biopolymers. The most innovative method is adding metal and metal oxide nanoparticles to the biopolymer with carefully regulated loads and parameters. This review aims to examine the barrier performance as well as their enhancement methods using metal, metal-oxide, and the synergetic effects of nanoparticles. Significant findingsThe review concludes that incorporating metallic and metallic oxide NPs into films has improved their barrier quality. The current and future materials in the property improvement field include metallic and metallic oxide nanoparticles, such as Ag, ZnO, GO, and TiO2, as well as their binary effects. Improvements to the barrier characteristics of bio-based films address the environmental and socioeconomic problems brought on by using petro-based films.

Enhanced photocatalytic activities of LaCoO3 perovskite nanostructures for degrading cationic and anionic dyes

Sustainable and cost-effective technologies are crucial for addressing environmental pollution issues. Perovskite photocatalysts have gained increased attention as a potential solution which could be accounted to their tuneable structural characteristics, flexible bandgap, and superior catalytic properties. In this study, we synthesized Lanthanum Cobaltite (LaCoO3) perovskite nanostructures via co-precipitation for photocatalytic purposes. Morphological analysis revealed LaCoO3 nanoparticles with an average size of ∼33 nm whose crystalline characteristics were investigated as a function of annealing temperatures. We found that the pure and crystalline LaCoO3 phase formed after the post-annealing process at 600°C. Photocatalytic studies showed that the degradation potential of LaCoO3 was significantly improved when hydrogen peroxide (H2O2) was added as co-catalyst system. We achieved degradation efficiencies of up to 91% and 85% for MB and methyl orange (MO), respectively. LaCoO3/H2O2 exhibited excellent photocatalytic potential for degrading both anionic and cationic organic dyes for environmental remediation applications.

Boosting tetracycline degradation of BaTiO3-based piezo-catalysts via modulating phase boundary and band structure

Piezoelectric catalysis, which converts mechanical energy into chemical activity, has important applications in environmental remediation. However, the piezo-catalytic activity of various piezoelectric materials is limited by the weak piezoelectricity as well as the mismatched band-gap, leading to inefficient electron-hole pair generation and difficult carrier migration. Here, a simple strategy combining phase boundary and energy band structure modulation was innovatively proposed to enhance the piezo-catalytic activity of BaTiO3 ferroelectric by Ce ions selecting different doping sites. Thanks to the coexistence of tetragonal (P4mm) and orthorhombic (Amm2) phases effectively flattened the Gibbs free-energy and thus enhanced the piezoelectric activity, as well as suitable energy bandwidth facilitating the carrier migration were realized in the B-sites doped Ba(Ti0.95Ce0.05)O3. The degradation rate constant k of tetracycline (TC) was high to 30.56 × 10-3 min−1, which was 2.03 times higher than that of pure BaTiO3 and superior to most representative lead-free perovskite piezoelectric materials. Theoretical calculations validated that the charge density and high O2 and OH– adsorption energy on the Ba(Ti0.95Ce0.05)O3 surface promoted more efficient •O2– and •OH radicals conversion and bettered response to piezo-catalytic reaction. This work is important to design high-performance piezo-catalysts by synergistic regulation of phase boundary and energy band structure in perovskite materials for long-term antibiotic tetracycline removal.

Biomineralization induced synthesis and self-assembly of photocatalyst-enzyme hybrid system for highly efficient environmental remediation

The photocatalyst-enzyme hybrid systems (PEHSs) provided a promising method for environmental remediation by simultaneously harnessing the power of solar-energy conversion and biocatalysis. However, the use of PEHSs for environmental remediation was restricted by a complicated synthesis and assembly process. This work explored a simple one-pot biomineralization approach to fabricate PEHS. It was found that the cytochrome enzyme could be directly self-assembled onto the biosynthesized CdS during biomineralization by Shewanella oneidensis MR-1. More strikingly, those attached cytochrome enzymes could efficiently receive the photoelectrons from the CdS and serve as the photoreduction center which formed a typical PEHS. Impressively, this bio-CdS-cytochrome PEHS exhibited an extremely high photocatalytic decolorization rate of 69.4 mg/g/min, which was the highest record ever reported for procion red H-E3B. This work provided a simple and facile approach for PEHSs fabrication, which would be promising for practical application in environmental remediation.

A customized 3D bio-macroporous cryogels for efficient and selective gold extraction

The swift and efficient extraction of gold from electronic wastes carries significant economic and environmental benefits. In the present work, chitosan and keratin were modified with vinyl pyrrolidone via grafting cryopolymerization used UV-irradiation for efficient Au(III) removal from actual electronic waste solution. The rapidly attaining adsorption equilibrium for Au(III) within just 4 h can be attributed to the biosorbent macroporous nature. Under ideal conditions (C0 = 1200 mg g−1, 308 K and pH 3), the Freundlich model exhibited superior fitting, showcasing the biosorbent's remarkable adsorption capacity for Au(III) at an impressive amount of 613.27 mg g−1. An Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES, Varian) was implemented to measure the adsorption of Au(III) and other coexisting ions. Additionally, the biosorbent displayed enhanced thermal stability and a prolonged shelf-life, indicating its potential for use in challenging environmental conditions. In addition to its stability, the material maintained its Au(III) adsorption efficiency after four consecutive usage cycles. In addition, it exhibited the capacity to specifically adsorb Au(III) from leaching solutions of electronic waste, resulting in a recovery rate of 89.2 %. The presence of amino (–NH2) and sulfide (-S-S-) functional groups on the biosorbent played a pivotal role in capturing Au(III) ions through electrostatic and chelation mechanisms. The presence of sulfide linkage and amino (–NH2) functionality, a major component of keratin is a pristine factor in this study, particularly well-suited for Au(III) extraction. The crosslinked biosorbent introduced random pores due to its random cooling process, enabling efficient diffusion and more significant Au(III) retention than traditional gels. In addition to its capacity for recovering precious metals from electronic waste, this biosorbent is a cost-effective solution with promising applications in environmental remediation and wastewater treatment.

Enhanced peroxymonosulfate activation by S-scheme AgI/Cu-BiVO4 heterojunction for efficient photocatalytic organics degradation and Microcystis aeruginosa inactivation: Performance, interfacial engineering and mechanism insight

Novel oxygen vacancies-enriched AgI/Cu-BiVO4 (ACBV) S-scheme heterojunction catalysts were constructed to boost photocatalytic organics degradation and M. aeruginosa inactivation with peroxymonosulfate (PMS) assistance. Specific interfacial charge transfer and abundant active centers were guided by introducing Cu doping and AgI coupling into BiVO4, with the catalytic activity and mechanism systematically investigated. The optimal 0.25-ACBV heterojunction exhibited 97.6% tetracycline (TC) degradation under PMS-assisted visible light and achieved effective inactivation of M. aeruginosa within 20 min (78.8%). The S-scheme heterostructure from Cu-BiVO4 to AgI and synergistic effects endowed the system with high-energy carrier transfer kinetics and strong oxygen reduction capability. Meanwhile, the redox cycling of Cu2+/Cu+ and surface oxygen defects served as electron acceptors to accelerate interfacial charge separation and as adsorption activation sites for PMS, promoting efficient mass transfer in the non-homogeneous system. This study inspires the design of high-performance S-scheme photocatalytic activators and expands their potential applications in environmental remediation.

Effects of Fe(II) and humic acid on U(VI) mobilization onto oxidized carbon nanofibers derived from the pyrolysis of bacterial cellulose

The effects of Fe(II) and humic acid on U(VI) immobilization onto oxidized carbon nanofibers (Ox-CNFs, pyrolysis of bacterial cellulose) were investigated by batch, spectroscopic and modeling techniques, with results suggesting that, Ox-CNFs exhibited fast adsorption rate (adsorption equilibrium within 3 h), high adsorption performance (maximum adsorption capacity of 208.4 mg/g), good recyclability (no notable change after five regenerations) in the presence of Fe(II) towards U(VI) from aqueous solutions (e.g., 40 % reduction and 10 % adsorption at pH 8.0), which was attributed to the various oxygen-containing functional groups, excellent chemical stability, large specific surface area and high redox effect. U(VI) adsorption increased with increasing pH from 2.0 to 5.0, then high-level plateau and remarkable decrease were observed at 5.0–6.0 and at pH > 6.0, respectively. According to FT-IR and XPS analysis, a negative correlation between U(VI) reduction and organic in the presence of Fe(II) implied that U(VI) reduction was driven by Fe(II) while inhibited by humic acid. The interaction mechanism of U(VI) on Ox-CNFs was demonstrated to be adsorption and ion exchange at low pH and reduction at high pH according to XPS and surface complexation modeling. These findings filled the knowledge gaps pertaining to the effect of Fe(II) on the transformation and fate of U(VI) in the actual environment. This carbon material with distinctive performance and unique topology offers a potential platform for actual application in environmental remediation.

Carbon Nanotubes as Adsorbents for Heavy Metals: Focus on Arsenic and Hydrargyrum Removal from Water

Water is the most common and indissoluble substance in the ecosystem. It is really sad that the development of cities, people, and industries has side effects on water resources, as they are getting worse. Heavy metals are mostly found in industries; their toxicity levels are a big challenge. The work details the latest methods employed in the removal of water contaminants with heavy metals, absorption being the technique used. Following the completeness of the literature review for various sorbents that are used to remove heavy metals from wastewater, this article details one of the possible sorbents that can play this role, using carbon nanotubes as a sorbent. Through the test, it has been demonstrated that CNTs have high efficiency, yet some shortcomings have also been shown. It should, additionally, be known that further improvement of desulfurizing agents to make them better at removing heavy metals is needed. This work demonstrates that, in comparison to IL's, which must be supplied by producers, DES's, as an alternative approach, are cheaper, more accessible to use, and much safer for the environment. In other words, the method of adsorption with functionalized CNTs + DESs proved to be the most suitable. The practical diagnostics and conclusions generated from this research should prove valuable to engineers and environmental scientists involved in carbon nanotube applications in environmental remediation.

Integration of Ag2S QDs in 3D Zn3V2O8 nanoflower for visible light driven effective photocatalytic degradation of rifampicin: Insights into preparation, mechanism and by-product toxicity evaluation

Water contamination is regarded as one of the most important concerns in the last decade and its crucial to develop an efficient and productive technique to remediate organic pollutants from waters. Photocatalytic degradation processesare advanced oxidation procedure and a promising technique for the degradation of organic pollutants. In this study, we fabricated Ag2S/Zn3V2O8 nanocomposite (AS/ZVO NCs) for the degradation of rifampicin (RIF) by ultrasonicated co-precipitation strategy. The NCs was optimally synthesized with varying deposition concentrations, among which 5%-Ag2S/Zn3V2O8 (5%-AS/ZVO) exhibited superior photocatalytic activity (95.5%) under visible light irradiation. Moreover, the experiments were conducted at diverse operational parameters such as different NCs dosage, different concentration of RIF, pH, and ions, to investigate the impact on the photocatalytic degradation of RIF. Notably, XRD and XPS results of used 5%-AS/ZVO NCs demonstrated commendable stability and possess sustained integrity in structure after six consecutive cycle tests. The scavenging study and radical trapping experiments confirmed the formation of •OH and O2•- during photocatalytic reaction. The mechanism of photocatalytic degradation of RIF by 5%-AS/ZVO NCs was proposed and the pathway was predicted based on the GC-MS results. The current study provides a comprehensive understanding for designing efficient photocatalysts for the environmental remediation applications.

Important soil microbiota's effects on plants and soils: a comprehensive 30-year systematic literature review.

Clarifying the relationship between soil microorganisms and the plant-soil system is crucial for encouraging the sustainable development of ecosystems, as soil microorganisms serve a variety of functional roles in the plant-soil system. In this work, the influence mechanisms of significant soil microbial groups on the plant-soil system and their applications in environmental remediation over the previous 30 years were reviewed using a systematic literature review (SLR) methodology. The findings demonstrated that: (1) There has been a general upward trend in the number of publications on significant microorganisms, including bacteria, fungi, and archaea. (2) Bacteria and fungi influence soil development and plant growth through organic matter decomposition, nitrogen, phosphorus, and potassium element dissolution, symbiotic relationships, plant growth hormone production, pathogen inhibition, and plant resistance induction. Archaea aid in the growth of plants by breaking down low-molecular-weight organic matter, participating in element cycles, producing plant growth hormones, and suppressing infections. (3) Microorganism principles are utilized in soil remediation, biofertilizer production, denitrification, and phosphorus removal, effectively reducing environmental pollution, preventing soil pathogen invasion, protecting vegetation health, and promoting plant growth. The three important microbial groups collectively regulate the plant-soil ecosystem and help maintain its relative stability. This work systematically summarizes the principles of important microbial groups influence plant-soil systems, providing a theoretical reference for how to control soil microbes in order to restore damaged ecosystems and enhance ecosystem resilience in the future.

Green synthesis of iron nanoparticles from the baru (Dipteryx alata) endocarp extract for the efficient removal of rhodamine B and caffeine from water through the heterogeneous Fenton process

Abstract This study presents the first-time synthesis of iron nanoparticles (FeNPs) using an aqueous extract from the baru fruit endocarp (Dipteryx alata). Characterization through scanning electron microscopy and dynamic light scattering revealed spherical shapes with an average diameter of 419.2 nm. Fourier transform infrared spectroscopy identified phytochemicals from the baru fruit extract, acting as both reducing and stabilizing agents. X-ray diffraction confirmed the amorphous nature of the FeNPs. The Fenton-like catalytic efficiency of FeNPs was investigated for degrading rhodamine B (RhB) and caffeine. The impact of crucial parameters such as pH, H2O2 dosage, nanoparticles concentration, and temperature on the degradation process was assessed. At pH 3.0, with 1.0 g L−1 of FeNPs, 1% H2O2, and 45 °C, RhB and caffeine degradation reached 99.14 and 92.01%, respectively. The catalytic reaction kinetics followed a pseudo-first-order model for caffeine and a pseudo-second-order model for RhB. Phytotoxicity studies on Cucumis sativus confirmed the non-toxic nature of the degraded products of RhB and caffeine. These findings highlight the potential of FeNPs synthesized from the baru endocarp extract as a catalyst for removing organic pollutants, suggesting promising applications in environmental remediation and related fields.

Graphitic carbon nitride based fluorine-free hydrophobic sponges for the mitigation of microplastics, oil spillage, and harmful microbial growth in water

Water pollution poses significant environmental challenges due to the pervasive presence of microplastics, frequent oil spillage, and the proliferation of harmful microbial populations. Addressing these multifaceted pollution issues often necessitates distinct treatment strategies, potentially compromising the economic viability and causing secondary pollution. In response, this study presents a novel approach by developing three-dimensional sponges with interconnected pores to simultaneously combat these environmental concerns. In this work, Hexadecyltrimethoxysilane functionalized graphitic carbon nitride (h-GCN) hydrophobic sponges were fabricated in a simple and scalable method. The sponges with varying porosity and hydrophobicity were fabricated by controlling the amount of NaCl as the hard sacrificial agent incorporated into the Polydimethylsiloxane matrix. The hierarchical surface irregularity and surface energy of the sponges were influenced by the addition of h-GCN content. The resulting sponges showed remarkable properties of oil/organic solvent-water separation ability of 116 % for mineral oil to 832 % for chloroform. Leveraging their extensive porosity and hydrophobic nature, the sponges demonstrated near-complete removal of Poly (methyl methacrylate) (PMMA) microplastic particles from aqueous solutions. The hydrophobic sponges also showed excellent bacteriostatic properties by inhibiting the growth of Escherichia coli and Staphylococcus aureus. We anticipate that these fluorine-free hydrophobic sponges, with their multifaceted capability to mitigate diverse water pollutants and exhibit robust recyclability, hold promise for a range of environmental remediation applications.

Industrial dye effluent degradation and in-vitro biological characteristics of MgO NPs anchored few layered g-C3N4 nanoribbons

In recent years, contaminated water consumption by humans and animals are lead to various types of diseases and environmental pollutant. Especially textile dye effluents are the highest contaminants in water bodies than any other industries. This article reports a green process for synthesizing MgO nanoparticles supported by the exfoliated g-C3N4 nano composites for dye effluent treatment. The cubic and hexagonal phase structure was achieved for synthesized MgO NPs and E-GCN, respectively, with spherical and curled ribbon-like morphology. The specific surface area was measured as 70.48, 54.22, and 79.11 m2/g, respectively, for MgO NPs, E-GCN, and MgO/E-GCN nanocomposite. Similarly, corresponding optical properties were achieved with an energy gap of 3.42, 2.48, and 2.78 eV. XPS analysis confirms the formation of MgO/E-GCN nanocomposite by detecting their characteristic elemental peaks. The bioactivities including antibacterial, turbidimetric, and antioxidant efficacy, were also investigated. Thus, the MgO/E-GCN nanocomposites was exhibitd greater susceptibility against pathogenic bacteria due to its production of high reactive oxygen species. Further, the catalysts were used to degrade cationic dye (Crystal Violet) and anionic dye (Eosin Yellow) under sunlight exposure. The photocatalytic efficiency of MgO/E-GCN nanocomposite was highly influenced towards CV (98.9 %) and EY (97.33 %) dye degradation, because of its high surface area with active UV–Visible region. Therefore, the combination of naturally inspired MgO NPs and morphologically modified E-GCN nanocomposites are being a sustainable material development for environmental remediation and biological applications.

Enhancing photocatalytic performance of Cu6Fe2SnS8 by N doping using magnetic grinding method

Nitrogen doped quaternary metal sulfide Cu6Fe2SnS8 (CFTS) was prepared by magnetic grinding. The mechanochemical method has the advantage of simple synthesis of non-metallic doped polymetallic sulfides, and there is no solvent involved in the reaction process, which is very environmentally friendly. Non metallic doping can form electron capture centers on semiconductors, suppress the recombination of photo generated electron hole pairs, and extend electron lifetime. Moreover, doping N element into the CFTS lattice will lead to the formation of new energy states, thereby narrowing the energy band gap. The characterizations of XPS and EDS have proven the successful doping of N element into CFTS. In addition, the photocatalytic mechanism and the stability of the N-doped CFTS (N-CFTS) were studied through active substance capture experiments and cyclic experiments. The experimental results indicate that ·O2− is the main active substance in the degradation of MB by N-CFTS. After multiple cyclic experiment, the N-CFTS catalytic material still exhibits good crystal structure and photocatalytic stability. This photocatalytic material has great potential for applications in wastewater treatment and environmental remediation.

Copper oxide combing with multi-walled carbon nanotubes activated peroxyacetic acid for the degradation of sulfamethoxazole

In this study, a stable and efficient catalyst, copper oxide composite multi-walled carbon nanotubes (CuxO@MWCNTs), was prepared by a sol-gel method for the activation of peracetic acid (PAA) for the degradation of sulfamethoxazole (SMX) in water. The catalyst exhibited excellent adsorption properties, and the MWCNTs promoted electron transfer between Cu+/Cu2+ and formed a synergistic catalytic effect for rapid activation of PAA to generate reactants with a wide pH applicability. Under the condition of PAA concentration of 0.1 mM, SMX dosage of 1.5 mg·L−1, catalyst concentration of 200 mg·L−1, pH = 7, and reaction temperature of 25 °C, the complete degradation of SMX was achieved in the CuxO@MWCNTs/PAA system within 16 min. The reaction mechanism of the CuxO@MWCNTs/PAA system was systematically investigated through quenching experiments, electron spin resonance spectra, and the result of X-ray photoelectron spectroscopy. Radical and non-radical pathways were determined, and unlike most of previous studies, singlet oxygen (non-radical pathway) was the main reactive species for SMX degradation in this study. In addition, CuxO@MWCNTs maintained good activity and stability. This study provided a green and efficient technique for removing antibiotics from water and offered new ideas for application in environmental remediation.

Enhancement of SrTiO3 photocatalytic efficiency by Al doping: Answers from the structure, morphology and electronic properties contributions

Our study focuses on disclosing the mechanisms standing behind the improved photocatalytic performance of SrTiO3, where Al modification of the perovskite structure boosts the photocatalytic O2 evolution activity of the Al:SrTiO3 system. By adapting the synthesis method that produces well-crystallized materials with low defect density and employing surface modification techniques, we aim to enhance the photocatalytic efficiency of SrTiO3via Al2O3 nanoceramic oxide doping at concentrations ranging from 0 to 10% and further examining of the relationship between doping process and the changes in the electronic and crystalline structure of SrTiO3. The prepared Al-based SrTiO3 perovskite samples (Al3%:SrTiO3, Al7%:SrTiO3, Al10%:SrTiO3) were thoroughly characterized to understand their structural, electronic, and morphological properties. Complementary X-ray techniques were employed to assess the stoichiometry (X-ray photoelectron spectroscopy - XPS), local environment, and chemical state (X-ray absorption spectroscopy - XAS in both total electron yield (TEY) and fluorescence yield (TFY). The comprehensive characterization enables us to understand the changes in the electronic properties and morphological features of the modified samples elucidating the surface formation mechanism while providing insights into the structural modifications induced by Al doping in the SrTiO3 perovskite lattice. Our findings give new perspectives for the development of Al-modified SrTiO3 perovskite materials with enhanced photocatalytic performance providing rich insights into the optimization of photocatalytic processes for applications in environmental remediation and sustainable energy production.

Functional upcycling of waste PET plastic to the hybrid magnetic microparticles adsorbent for cesium removal

Accumulation of mismanaged plastic in the environment and the appearance of emerging plastic-derived pollutants such as microplastics strongly demand technologies for waste plastic utilization. In this study, polyethylene terephthalate (PET) from waste plastic bottles was directly utilized to prepare a matrix of an adsorbent for cesium (Cs+) removal. The organic matrix of PET-derived oligomers obtained by aminolysis depolymerization was impregnated with bentonite clay and magnetite nanoparticles (Fe3O4 NPs), playing the roles as a major adsorptive medium for Cs+ removal and as a functional component to primarily provide efficient separation of the hybrid adsorbent from aqueous system, respectively. The obtained hybrid composite microparticles were next tested as an adsorbent for the removal of Cs+ cation from aqueous solutions. The adsorption process was characterized by fast kinetics reaching ca. 60% of the equilibrium adsorption capacity within 5 min and the maximum adsorption capacity toward Cs+ was found to be 26.8 mg/g. The adsorption process was primarily dominated by the cationic exchange in bentonite, which was not significantly affected by the admixture of the competing mono- and divalent cations (Na+, K+, and Mg2+). The proposed approach here exploits the sustainable utilization scenario of plastic waste-derived material to template complex multifunctional nanocomposites that can find applications for pollution cleaning and environmental remediation.

Novel SnO2-modified hydrozincite photocatalyst: Material design and application in efficient micropollutants degradation in wastewater

In this work novel photocatalysts have been synthesized based on hydrozincite and SnO2 with varying mol% of SnO2 in hydrozincite. The photocatalysts were prepared via chemical co-precipitation using thermal urea hydrolysis, without calcination or activation processes, and were applied in the photodegradation of micropollutants (in this case, several phenolic compounds). Characterization of the materials using various techniques revealed that the generation of hydroxyl radicals, holes, and superoxide radicals played crucial roles in the photodegradation process. The best photocatalyst was achieved with a 10 mol% SnO2 content in hydrozincite, which shows the highest rate in the pollutants degradation (higher than 93% in all the cases), also higher than TiO2-P25This study presents promising insights for developing highly efficient photocatalytic materials for environmental remediation applications.