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Converting lignin into specific aromatic chemicals for utilization through depolymerization of lignin is an effective way to achieve high-value applications. There are many depolymerization methods that can do this, but there are problems such as harsh reaction conditions, low depolymerization efficiency and uncontrollable target products that need to be solved. This study reports a novel system for the oxidative depolymerization of alkali lignin using Fe- and Mn- modified TS-1 as a catalyst to assist in the highly selective production of vanillin. We also proposed a possible reaction pathway for the oxidative depolymerization of alkali lignin to produce vanillin catalyzed by Fe-Mn/TS-1 catalyst. The catalytic effects of TS-1, Fe/TS-1, and Fe-Mn/TS-1 catalysts on the oxidative depolymerization of lignin to produce phenolic monomers and vanillin were investigated. The results show that the modified catalysts can effectively improve the efficiency of linkage bond breaking in lignin, especially the β-O-4 bond, in which the inter-band transitions of Fe and Mn play an important role. The synergistic effect of the bimetallic-loaded catalyst (Fe-Mn/TS-1) could catalyze the oxidative depolymerization of lignin more efficiently than the monometallic-loaded catalyst (Fe/TS-1). This lignin oxidative depolymerization system produced 40.59 wt% bio-oil including 12.24 wt% phenolic monomers and 16.17 wt% re-lignin after the addition of Fe-Mn/TS-1 catalyst, owning the highest phenolic monomer yield. Surprisingly, this lignin oxidative depolymerization system exhibited high yield for vanillin (8.36 wt%) production. These results demonstrated that the Fe-Mn/TS-1 catalytic system has potential to produce vanillin from lignin under mild conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Chitin is a popular hemostatic material, but there are still many deficiencies in its ability to effectively stop bleeding, prevent infection, and fit wounds. Herein, AgNP@zeolite/chitin/bamboo (AgZ-CB) composite sponges with shape recovery are prepared to minimize blood loss, kill bacteria, and promote wound healing. Notably, the bamboo powder is used for the first time to remarkably enhance the softness of the composite sponge (volumetric expansion ratio >5). The fabricated AgZ-CB sponge exhibits an excellent killing effect (≈100% bactericidal rate) against both Escherichia coli and Staphylococcus aureus and activates internal and external coagulation pathways to accelerate hemostasis without causing thermal damage (≈5 °C temperature difference). Moreover, the AgZ-CB sponge shows less blood loss (26 mg) and a shorter time to hemostasis (42 s) than the commercial polyvinyl formal sponge (84 mg and 76 s) in the full-thickness liver injury model. The in vivo wound healing and biodegradation experiment indicate that AgZ-CB with excellent biocompatibility can close wounds efficiently. Overall, the AgZ-CB sponge has great potential in combating a series of obstacles in wound healing., (© 2023 Wiley-VCH GmbH.)

Ethylene, a ripening hormone, is critical in limiting the shelf life of fresh produce, specifically climacteric fruits and vegetables. A simple and benign fabrication approach is used to transform sugarcane bagasse, an agro-industrial waste into lignocellulosic nanofibrils (LCNF). In this investigation, biodegradable film was fabricated using LCNF (extracted from sugarcane bagasse) and guar gum (GG) which was reinforced with zeolitic imidazolate framework (ZIF)-8/zeolite. The LCNF/GG film not only acts as a biodegradable matrix to hold the ZIF-8/zeolite composite, but also possesses ethylene scavenging, antioxidant, and UV-blocking properties. The characterization results suggested that pure LCNF showed antioxidant activity of around 69.55 %. The LCNF/GG/MOF-4 film has shown lowest UV-transmittance (5.06 %) and highest ethylene scavenging capacity (40.2 %) among all the samples. After 6 days of storage at 25 ± 2 °C, packaged control bananas samples underwent significant degradation. In contrast, a banana package consisting of LCNF/GG/MOF-4 film maintained their high quality in terms of colour. Fabricated novel biodegradable film has potential application prospects for being used in prolonging the shelf life of fresh produce., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Zeolitic imidazolate frameworks (ZIFs) can be used as adsorbent to efficiently adsorb organic pollutants. However, the hydrophobicity of the ZIFs may be easily to form ZIFs nanoparticles aggregates, hampering the effective and practical application in adsorption. In this study, novel spherical composites of ZIF-8 incorporated with lignosulfonate (LS) were synthesized by in-situ growth method. The effects of different mass ratios of LS and Zn in ZIF-8-LS composites were evaluated with respect to structural characteristics and adsorption properties. As an adsorbent for adsorptive removing Congo Red (CR) and tetracycline (TC) from water, the prepared ZIF-8-LS 4 shows the best adsorption capacity of 31.5 mg g -1 and 48 mg g -1 , respectively. The spherical structure facilitates the contact between the ZIF-8 and the adsorbed substance, in addition to the H-bonding, electrostatic and π-π stacking interactions also contribute to the improvement of the adsorption performance of the ZIF-8-LS 4 composite. The outstanding adsorption capacity and good reusability of the ZIF-8-LS 4 composite provide a good prospect for the effective removal of other contaminants from water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Robust biopolymer-based composite film with multifunctional performances significantly contributes to the packaging field. Herein, we proposed a sort of carboxymethyl cellulose (CMC) based composite film via incorporating versatile zeolitic imidazolate framework (ZIF) materials. Compared to pristine CMC film, the OTR, WVTR, and tensile strength of CMC/ZIF composite film with 1 wt ‰ Zn/Co-ZIF were improved from 64.89 cm 3 *μm/(m 2 *d*kPa), 1579.21 g/(m 2 *24h) and 16.9 MPa to 20.79 cm 3 *μm/(m 2 *d*kPa), 1209.58 g/(m 2 *24h) and 70.1 MPa, respectively. Notably, owing to the reduced band gap and intrinsic chemical and thermal stability of Zn/Co-ZIF, the fabricated Zn/Co-ZIF/CMC composite film presented well UV protection capability within the whole UV region and excellent UV-blocking durability after being exposed to UV-light at 365 nm for 12 h. In practice, the photocatalytic degradation of RhB solutions under UV light could be effectively suppressed when using Zn/Co-ZIF/CMC film as UV protection layer. Our findings proposed the potential application of these versatile ZIF materials as functional nanofiller within biopolymer substances for UV protection and transparent packaging area., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Biobased N-doped hierarchically porous carbon (N-HPC) electrodes were successfully prepared by utilizing marine crustacean derivatives and chitin nanofibers (ChNF), as versatile bio-templates of zeolitic imidazolate frameworks (ZIF-8) to form ChNF@ZIF-8 nanocomposites, followed by a subsequent carbonization process. The ZIF-8 nanoparticles were in situ synthesized on ChNF surfaces to avoid fragmentation for fabricating hierarchically porous carbon structure (N-HPC), which is efficiently doped with rich nitrogen content that originates in ChNF and ZIF-8. The results show that N-HPC electrodes demonstrate improved electrochemical performance and the constructed symmetric supercapacitor assembled with N-HPC exhibits enhanced capacitive performance of specific capacity (128.5 F·g -1 at 0.2 A·g -1 ) and excellent electrochemical stability even after 5000 cycles. This facile and effective preparation method of N-HPC electrodes derived from marine crustacean nanomaterials will have great potential in the construction of next-generation electrochemical energy-storage devices with excellent capacitance performance., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Crotamiton, a scabicide and antipruritic agent persistent during biological treatment processes, is frequently detected in secondary effluent. In this study, titanium dioxide (TiO 2 ) and high-silica zeolite (HSZ-385) composites were synthesized and applied for the treatment of crotamiton in secondary effluent. Crotamiton was rapidly adsorbed by HSZ-385, and the adsorption performance of crotamiton in the secondary effluent was quite close to that in the test using ultrapure water. Even though the TiO 2 -zeolite composites showed lower adsorption rates than that of HSZ-385, similar crotamiton adsorption capacities were revealed using both test materials. The photocatalytic decomposition of crotamiton was significantly inhibited by the water matrix at low initial concentrations. The TiO 2 -zeolite composites rapidly adsorbed crotamiton from secondary effluent, and then the crotamiton was gradually decomposed under ultraviolet irradiation. Importantly, when using TiO 2 -zeolite composites, coexisting material in the secondary effluent did not markedly inhibit crotamiton removal at low initial crotamiton concentration. The behaviors of the main intermediates during treatment demonstrated that the main degradation intermediates of crotamiton were also captured by the composites.

In this study, surfactant modified zeolite-clinoptilolite (SMZ) by CPB (cetylpyridinium bromide) was used for simultaneous removal of ammonium, nitrate and phosphate in synthetic wastewater, and the sorption properties of SMZ were determined and compared with natural zeolite. Results showed that natural clinoptilolite had good affinity for ammonium (8.940 mg/g), but not for nitrate (0.427 mg/g) and phosphate (0.801 mg/g). With the increase of surfactant loading from 5 g/L to 40 g/L, the sorption capacity for nitrate increased from 0.462 mg/g to 4.661 mg/g. when the surfactant loading is 40 g/L, the SMZ has a phosphate adsorption capacity of 2.119 mg/g. The SMZ had a significant enhancement on nitrate and phosphate sorption, could simultaneously remove ammonium, nitrate and phosphate at specific conditions, with removal efficiency up to 85.2%, 83.1% and 56.7%, respectively. Orthogonal experiments showed that ammonium concentration was the most important factor for ammonium sorption on SMZ. Surfactant loading was the major factor for nitrate and phosphate sorption. With the increase of surfactant loading from 5 g/L to 40 g/L, the sorption capacity for nitrate increased from 0.462 mg/g to 4.661 mg/g. When the surfactant loading is 40 g/L, the SMZ has the best phosphate adsorption capacity 2.119 mg/g. Samples were characterized by X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET). Semi-empirical quantum mechanics molecular simulation indicated that electrostatic attraction existed between CPB and dihydrogen phosphate ion. Results indicate that SMZs might have great potential of removing cations and anions simultaneously in the aquatic environment, which is good for eutrophication control and nutrients removal.

Removal efficiencies of sulfamonomethoxine (SMM) and its degradation intermediates formed by treatment with zeolite/TiO 2 composites through adsorption and photocatalysis were investigated in fresh aquaculture wastewater (FAWW). Coexistent substances in the FAWW showed no inhibitory effects against SMM adsorption. Although coexistent substances in the FAWW inhibited the photocatalytic decomposition of SMM, the composites mitigated the inhibition, possibly because of concentration of SMM on their surface by adsorption. LC/MS/MS analyses revealed that hydroxylation of amino phenyl and pyrimidinyl portions, transformation of the amino group in the amino phenyl portion into a nitroso group, and substitution of the methoxy group with a hydroxyl group occurring in the initial reaction resulted in the formation of various intermediates during the photocatalysis of SMM. All detected intermediates had a ring structure, and almost all intermediates disappeared at the same time SMM was completely decomposed. Ph-OH formed by hydroxylation of the phenyl portion was detected upon decomposition of SMM during photocatalysis. The removal of Ph-OH by the composites proceeded more rapidly than that by TiO 2 alone under ultraviolet irradiation. The SMM and Ph-OH were completely degraded by the composites within 30min, showing that the zeolite/TiO 2 composites were effective in removing SMM and its intermediates from FAWW., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Zeolite was synthesized from coal fly ash by a fusion method and was used for the removal of heavy metal ions (Pb(2+), Cd(2+), Cu(2+), Ni(2+), and Mn(2+)) in aqueous solutions. Batch method was employed to study the influential parameters such as adsorbent dosage, pH, and coexisting cations. Adsorption isotherms and kinetics studies were carried out in single-heavy and multiheavy metal systems, respectively. The Langmuir isotherm model fitted to the equilibrium data better than the Freundlich model did, and the kinetics of the adsorption were well described by the pseudo-second-order model, except for Cd(2+) and Ni(2+) ions which were fitted for the pseudo-first-order model in the multiheavy metal system. The maximum adsorption capacity and the distribution coefficients exhibited the same sequence for Pb(2+) > Cu(2+) > Cd(2+) > Ni(2+) > Mn(2+) in both single- and multiheavy metal systems. In the end, the adsorption capacity of zeolite was tested using industrial wastewaters and the results demonstrated that zeolite could be used as an alternative adsorbent for the removal of heavy metal ions from industrial wastewater.

This study aimed to produce furfural from waste aqueous hemicellulose solution of a hardwood kraft-based dissolving pulp production processing in a green method. The maximum furfural yield of 82.4% and the xylose conversion of 96.8% were achieved at 463K, 1.0g ZSM-5, 1.05g NaCl and organic solvent-to-aqueous phase ratio of 30:15 (V/V) for 3h. The furfural yield was just 51.5% when the same concentration of pure xylose solution was used. Under the optimized condition, furfural yield was still up to 67.1% even after the fifth reused of catalyst. Catalyst recycling study showed that ZSM-5 has a certain stability and can be efficiently reused., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

TiO(2)/high-silica zeolite composite synthesized by a sol-gel method was applied for the removal of sulfamethazine (SMT) antibiotic from water, and simple models including both adsorption and photocatalytic decomposition were developed. In this study, two types of models were constructed: a synergistic model that included the interaction between the zeolite and TiO(2) in the composite, and an individual model, which did not include the interaction. We obtained rate constants for adsorption, desorption and photocatalytic decomposition experimentally, and compared them with the results calculated using the synergistic and individual models. The individual model predicted that ca. 55% of SMT would be removed from the system after 6h of treatment; however, our experiments showed that 80% of the SMT was removed, suggesting the existence of another reaction pathway. Therefore, a synergistic model was constructed, in which, part of the SMT was adsorbed onto the zeolite within the composite, desorbed from the zeolite and migrated to the TiO(2), and was then photocatalytically decomposed. Experiments were carried out with varying amounts of the TiO2-zeolite composite, and the synergistic model was validated. We estimated that 10% of the desorbed SMT was photocatalytically decomposed without being released into the water. When TiO(2)-zeolite composite concentrations were 0.04, 0.12 and 0.20g/L, and the treatment time was 6h, the proportions of the total decomposition of SMT that occurred via this synergistic reaction pathway were calculated as 52.2%, 58.6% and 66.7%, respectively. In other words, over half of the SMT was decomposed through the synergistic reaction, which played a very significant role in the overall removal of SMT (the remainder of the SMT was decomposed through simple photocatalysis on the TiO(2))., (Copyright © 2014 Elsevier B.V. All rights reserved.)