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Phenol is a volatile organic compound, and conventional treatment processes prove to be ineffective for its degradation. The designable electron transfer structures of Fenton-based catalysts show great potential for wastewater treatment. However, attaining a balance between recycling and degradation efficiency remains a challenge. Herein, we prepared a photocatalyst with improved visible-light excitation characteristics. Magnetic N-TiO2/Fe3O4@MXene was prepared by loading N-TiO2 nanoparticles and Fe3O4 onto multilayered MXenes. N-TiO2/Fe3O4@MXene exhibited stable magnetic characteristics (27.1 emu/g) and a high degradation capacity for phenol. The catalyst also showed better performance for phenol removal under simulated solar-light (200–800 nm) irradiation compared with those of other catalysts. The phenol removal rate of the catalyst in the concentration range of 20–60 ppm reached 98% after 30 min of solar-light irradiation. The degradation curves of phenol were kinetically fitted. After four cycles of testing, the material maintained a high efficiency for the degradation of phenol. A total organic carbon removal rate of 61% was achieved in 10 min. The intermediates of phenol degradation were determined via liquid chromatography–mass spectrometry to gain insights into the degradation pathways of phenol. This study paves the way for the development of efficient photo-Fenton-based catalytic systems with good magnetic separation capabilities, which can promote their application in wastewater treatment. [ABSTRACT FROM AUTHOR]

What should be done after an adsorbent has adsorbed heavy metals? Most previous studies on adsorption materials only focused on the preparation method and adsorption capacity and seldom considered the potential pollution of hazardous waste adsorbents. In this study, we not only designed an Amination@Wood-Aerogel (AWA) bulk adsorbent with easy recovery and high adsorption capacity for Zn(II) (400 mg L−1, 297.03 mg g−1) but also for the first time proposed a novel high-value reuse strategy for the in situ conversion of Zn(II) adsorbed onto AWA to ZnO/ZnS n-type heterojunction photocatalyst (ZnO/ZnS@AWA) via in situ chemical deposition, which will be further used for the photocatalytic degradation of Congo red. The adsorption sites (–OH, –COOH, –NH2) on the AWA surface ensure that ZnO/ZnS could cover the AWA surface evenly with strong interfacial bonding strength. ZnO/ZnS@AWA successfully photocatalytically degraded Congo red (40 mg L−1, 98.84%) through the synergistic degradation mechanism of adsorption and photocatalysis. This work proposes a new protocol for wood-based bulk adsorbents and provides a high-value reuse strategy for solving the potential pollution of hazardous waste adsorbents. It is indisputable that we point out a new direction to design adsorbents with high adsorption capacity and high-value reuse. [ABSTRACT FROM AUTHOR]

This work reported the synthesis of Ce‐MOF and Nd‐MOF adsorption materials using the solvothermal method with the rare earth metals Ce3+ and Nd3+ as the particle center and discussed the adsorption effect of the two synthesized nanomaterials on the VOCs released by dry wood. The porous morphology of the material increases the benzene gas contact area. The maximum adsorption capacity of benzene, according to the Langmuir model, is 128.98 mg/g and 132.22 mg/g, respectively. The method has a large adsorption capacity, good adsorption effect, non‐toxic and harmless, low recycling cost, recyclable multiple times, simple operation, stable structure, no secondary environmental pollution, etc., and has good application prospects in the wood drying industry. [ABSTRACT FROM AUTHOR]

Zeolitic imidazolate framework-8 (ZIF-8) was evenly loaded on the surface of TiO2 doped with KI, using a solvent synthesis method, in order to produce a ZIF-8@TiO2 (KI) adsorption photocatalyst with good adsorption and photocatalytic properties. The samples were characterized by XRD, SEM, EDX, XPS, BET and UV-Vis. The photocatalytic efficiency of the material was obtained by photocatalytic tests. The results indicate that the doping with I inhibited the grain growth and reduced the crystallite size of TiO2, reduced the band gap width and improved the utilization rate for light. TiO2 (KI) was a single crystal of anatase titanium dioxide. The combination of ZIF-8 and TiO2 (KI) improved the specific surface area and increased the reaction site. The ZIF-8@TiO2 (KI) for Congo red was investigated to validate its photocatalytic performance. The optimal concentration of Congo red solution was 30 mg/L, and the amount of catalyst was proportional to the degradation efficiency. The degradation efficiency of ZIF-8@TiO2 (5%KI) was 76.42%, after being recycled four times. [ABSTRACT FROM AUTHOR]

Heavy metal wastewater treatment is a huge problem facing human beings, and the application degree of Salix psammophila resources produced by flat stubble is low. Therefore, it is very important to develop high-value products of Salix psammophila resources and apply them in the removal heavy metal from effluent. In this work, we extracted the cellulose from Salix psammophila, and cellulose nanofibers (CNFs) were prepared through TEMPO oxidation/ultrasound. The aerogel spheres derived from Salix psammophila (ASSP) were prepared with the hanging drop method. The experimental results showed that the Cu(II) adsorption capacity of the ASSP composite (267.64 mg/g) doped with TOCNF was significantly higher than that of pure cellulose aerogel spheres (52.75 mg/g). The presence of carboxyl and hydroxyl groups in ASSP enhanced the adsorption capacity of heavy metals. ASSP is an excellent heavy metal adsorbent, and its maximum adsorption values for Cu(II), Mn(II), and Zn(II) were found to be 272.69, 253.25, and 143.00 mg/g, respectively. The abandoned sand shrub resource of SP was used to adsorb heavy metals from effluent, which provides an important reference value for the development of forestry in this sandy area and will have a great application potential in the fields of the adsorption of heavy metals in soil and antibiotics in water. [ABSTRACT FROM AUTHOR]

Zeolitic imidazolate framework-8 (ZIF-8) was doped with a rare-earth metal, Eu, using a solvent synthesis method evenly on the surface of a mixed-crystal TiO2(Mc-TiO2) structure in order to produce a core–shell structure composite ZIF-8(Eu)@Mc-TiO2 adsorption photocatalyst with good adsorption and photocatalytic properties. The characterisation of ZIF-8(Eu)@Mc-TiO2 was performed via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller analysis (BET) and ultraviolet–visible light differential reflectance spectroscopy (UV-DRs). The results indicated that Eu-doped ZIF-8 was formed evenly on the Mc-TiO2 surface, a core–shell structure formed and the light-response range was enhanced greatly. The ZIF-8(Eu)@Mc-TiO2 for basic fuchsin was investigated to validate its photocatalytic performance. The effect of the Eu doping amount, basic fuchsin concentration and photocatalyst dosage on the photocatalytic efficiency were investigated. The results revealed that, when 5%-Eu-doped ZIF-8(Eu)@Mc-TiO2 (20 mg) was combined with 30 mg/L basic fuchsin (100 mL) under UV irradiation for 1 h, the photocatalytic efficiency could reach 99%. Further, it exhibited a good recycling performance. Thus, it shows certain advantages in its degradation rate and repeatability compared with previously reported materials. All of these factors suggested that, in an aqueous medium, ZIF-8(Eu)@Mc-TiO2 is an eco-friendly, sustainable and efficient material for the photocatalytic degradation of basic fuchsin. [ABSTRACT FROM AUTHOR]

Lignocellulose (LCE) was ultrasonically treated and intercalated into magnesium aluminum silicate (MOT) clay to prepare a nano-lignocellulose magnesium aluminum silicate polymer gel (nano-LCE-MOT) for the removal of Zn (II) from aqueous solution. The product was characterised using nitrogen adsorption/desorption isotherm measurements, Fourier-transform infrared spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The conditions for the adsorption of Zn (II) on nano-LCE-MOT were screened, and adsorption kinetics and isotherm model analysis were carried out to explore the adsorption mechanism and achieve the optimal adsorption of Zn (II). Optimal adsorption was achieved at an initial Zn (II) concentration of 800 mg/L at 60 °C in 160 min at a pH of 4.52. The adsorption kinetics were explored using a pseudo-second-order model, with the isotherm adsorption equilibrium found to conform to the Langmuir model. The maximum adsorption capacity of the nano-LCE-MOT polymer gel toward Zn (II) is 513.48 mg/g. The materials with adsorbed Zn (II) were desorbed using different media, with HCl found to be the most ideal medium to desorb Zn (II). The optimal desorption of Zn (II) was achieved in 0.08 mol/L HCl solution at 65 °C in 60 min. Under these conditions, Zn (II) was almost completely desorbed from the adsorbents, with the adsorption effect after cycling being slightly different from that of the initial adsorption. [ABSTRACT FROM AUTHOR]

A novel Mg(II) metal-organic framework (Mg-MOF) was synthesized based on the ligand of 2,2'-bipyridine-4,4'-dicarboxylic acid. Single-crystal X-ray structural analysis confirmed that three-dimensional-nanostructure Mg-MOFs formed a monoclinic system with a channel size of 15.733 Å × 23.736 Å. N 2 adsorption isotherm, Fourier transform infrared spectroscopy, thermogravimetric analysis and high-resolution transmission electron microscopy were performed to characterize the thermal stability and purity of the Mg-MOFs. The adsorption studies on four typical volatile organic compounds (VOCs) emitted during wood drying showed that Mg-MOFs have noteworthy adsorption capacities, especially for benzene and β-pinene with adsorptions of 182.26 mg g -1 and 144.42 mg g -1 , respectively. In addition, the adsorption of Mg-MOFs mainly occurred via natural adsorption, specifically, multi-layer physical adsorption, accompanied by chemical forces, which occurred in the pores where the VOCs molecules combined with active sites. As an adsorbent, Mg-MOFs exhibit versatile behaviour for toxic gas accumulation., Competing Interests: We declare we have no competing interests., (© 2022 The Authors.)