Wood-converted porous carbon decorated with MIL-101(Fe) derivatives for promoting photo-Fenton degradation of ciprofloxacin.

In response to the escalating concerns over antibiotics in aquatic environments, the photo-Fenton reaction has been spotlighted as a promising approach to address this issue. Herein, a novel heterogeneous photo-Fenton catalyst (Fe3O4/WPC) with magnetic recyclability was synthesized through a facile two-step process that included in situ growth and subsequent carbonization treatment. This catalyst was utilized to expedite the photocatalytic decomposition of ciprofloxacin (CIP) assisted by H2O2. Characterization results indicated the successful anchoring of MIL-101(Fe)-derived spindle-like Fe3O4 particles in the multi-channeled wood-converted porous carbon (WPC) scaffold. The as-synthesized hybrid photocatalysts, boasting a substantial specific surface area of 414.90 m2·g-1 and an excellent photocurrent density of 0.79 µA·cm-2, demonstrated superior photo-Fenton activity, accomplishing approximately 100% degradation of CIP within 120 min of ultraviolet-light exposure. This can be attributed to the existence of a heterojunction between Fe3O4 and WPC substrate that promotes the migration and enhances the efficient separation of photogenerated electron-hole pairs. Meanwhile, the Fe(III)/Fe(II) redox circulation and mesoporous wood carbon in the catalyst synergistically enhance the utilization of H2O and accelerate the formation of •OH radicals, leading to heightened degradation efficiency of CIP. Experiments utilizing chemical trapping techniques have demonstrated that •OH radicals are instrumental in the CIP degradation process. Furthermore, the study on reusability indicated that the efficiency in removing CIP remained at 89.5% even through five successive cycles, indicating the structural stability and excellent recyclability of Fe3O4/WPC. This research presented a novel pathway for designing magnetically reusable MOFs/wood-derived composites as photo-Fenton catalysts for actual wastewater treatment.

Development and Characterization of Bio-Based Formaldehyde Free Sucrose-Based Adhesive for Fabrication of Plywood.

In order to solve the problem of excessive consumption of petrochemical resources and the harm of free formaldehyde release to human health, biomass raw materials, such as sucrose (S) and ammonium dihydrogen phosphate (ADP) can be chemically condensed in a simple route under acidic conditions to produce a formaldehyde free wood adhesive (S-ADP), characterized by good storage stability and water resistance, and higher wet shear strength with respect to petroleum based phenolic resin adhesive. The dry and boiling shear strength of the plywood based on S-ADP adhesive are as high as 1.05 MPa and 1.19 MPa, respectively. Moreover, is Modulus of Elasticity (MOE) is as high as 4910 MPa. Interestingly, the plywood based on the developed S-ADP adhesive exhibited good flame retardancy. After burning for 90 s, its shape remains unchanged. Meanwhile, it can be concluded from thermomechanical analysis (TMA) and thermogravimetric analysis (TGA) that the S-ADP acquired excellent modulus of elasticity (MOE) and good thermal stability. It is thus thought promisingly that the use of S-ADP adhesive as a substitute for PF resin adhesive seems feasible in the near future.

Fungal Selectivity and Biodegradation Effects by White and Brown Rot Fungi for Wood Biomass Pretreatment.

The biodegradation path and mechanism of wood varies depending on diverse fungi and tree species, as fungi possess selectivity in degradation of versatile wood components. This paper aims to clarify the actual and precise selectivity of white and brown rot fungi and the biodegradation effects on different tree species. Softwood (Pinus yunnanensis and Cunninghamia lanceolata) and hardwood (Populus yunnanensis and Hevea brasiliensis) were subjected to a biopretreating process by white rot fungus Trametes versicolor, and brown rot fungi Gloeophyllum trabeum and Rhodonia placenta with various conversion periods. The results showed that the white rot fungus Trametes versicolor had a selective biodegradation in softwood, which preferentially convert wood hemicellulose and lignin, but cellulose was retained selectively. Conversely, Trametes versicolor achieved simultaneous conversion of cellulose, hemicellulose and lignin in hardwood. Both brown rot fungi species preferentially converted carbohydrates, but R. placenta had a selectivity for the conversion of cellulose. In addition, morphological observation showed that the microstructures within wood changed significantly, and the enlarged pores and the improved accessibility could be beneficial for the penetration and accessibility of treating substrates. The research outcomes could serve as fundamental knowhows and offer potentials for effective bioenergy production and bioengineering of bioresources, and provide a reference for further application of fungal biotechnology.

Tannin-Epoxidized Soybean Oil as Bio-Based Resin for Fabrication of Grinding Wheel.

Formaldehyde-free epoxidized soybean oil-based resin has been prepared under acidic conditions by co-condensation of the epoxidized soybean oil and condensed tannin originating from agricultural and forestry sources as the main raw materials, whereas 1,6-hexanediamine was employed as a cross-linking agent. Fourier transform infrared spectroscopy (FTIR) and electrospray ionization (ESI) corroborated that tannin and epoxidized soybean oil underwent crosslinking under acidic conditions supported by hexamethylenediamine. A bio-based grinding wheel was fabricated by formulation of the developed resin with wood powder as source of grinding particles. The appearance, hardness, compressive strength and wear resistance of the resulting grinding wheel were studied. The results have shown that the grinding wheel possesses a smooth surface with no bubbles or cracks, and its hardness and wear resistance were greater than that of a phenolic resin-based grinding wheel. Interestingly, the grinding wheel incorporates more than 90% of its raw materials as biomass renewable materials; thus, it is generally considered non-toxic. In addition, the future feasibility of this approach to replace some petrochemical resins that are frequently used in the fabrication of grinding wheels is considered.