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Abstract The use of γ‐Al₂O₃‐supported Ni catalysts promoted with either Cu or Fe was investigated for the reductive catalytic fractionation (RCF) of hybrid poplar in methanol at 200 and 250 °C. The effectiveness of lignin depolymerization was quantified in terms of the lignin oil production, the quantity and distribution of identifiable monomers present in the lignin oil, and the yield of residual solids. All of the Ni‐based catalysts tested provided improved yields of lignin oil and monomers, along with reduced char formation, relative to blank (sans catalyst) runs. The highest monomer yield of 51 % was obtained at 250 °C over a 20 wt.% Ni‐5 wt.% Cu/Al₂O₃catalyst, the improved performance obtained through Cu promotion being attributed to the ability of Cu to facilitate NiO reduction, resulting in an increased amount of Ni⁰on the catalyst surface and, consequently, improved hydrogenation activity. The main monomers formed were propanol‐, propyl‐ and propenyl‐substituted guaiacol and syringol, the S/G ratio of the products corresponding closely to that in the native lignin. 

Abstract Membranes serve as important components for modern manufacturing and purification processes but are conventionally associated with excessive solvent usage. Here, for the first time, a procedure for fabricating large area polysulfone membranes is demonstrated via the combination of direct ink writing (DIW) with non-solvent induced phase inversion (NIPS). The superior control and precision of this process allows for complete utilization of the polymer dope solution during membrane fabrication, thus enabling a significant reduction in material usage. Compared to doctor blade fabrication, a 63% reduction in dope solution volume was achieved using the DIW technique for fabricating similarly sized membranes. Cross flow filtration analysis revealed that, independent of the manufacturing method (DIWvs.doctor blade), the membranes exhibited near identical separation properties. The separation properties were assessed in terms of bovine serum albumin (BSA) rejection and permeances (pressure normalized flux) of pure water and BSA solution. This new manufacturing strategy allows for the reduction of material and solvent usage while providing a large toolkit of tunable parameters which can aid in advancing membrane technology. 

Phenolic aldehydes are widespread pollutants in water and soil, originating from lignin-based agro-industries. With increasing wastewater pollution, improved treatment systems are necessary to degrade phenolic aldehydes into less hazardous compounds. Over the past two decades, ozonolysis wastewater treatment has been implemented in the United States, Japan, and South Korea. However, the mechanistic understanding of phenolic aldehyde ozonolysis in water remains incomplete. This study investigates the ozonolysis of three model phenolic aldehydes (syringaldehyde, vanillin, 4-hydroxybenzaldehyde) in representative concentrations for wastewater of 0.5–1.5 mM and pH 4–8. Each compound solution was sparged for 30 min at a fixed O3(g) flow (0.20 to 1.00 L min−1), providing steady-state dissolved concentrations of 5.4 to 16.2 μM. Reactant loss and product generation were monitored using UV–visible (UV–vis) spectroscopy, ultra-high pressure liquid chromatography (UHPLC) with UV–vis and mass spectrometry (MS) detection, and ion chromatography with conductivity and MS detection of anions. Identified products based on their mass-to-charge ratio (m/z−) included oxalic acid (89), glycolic acid (75), formic acid (45), and maleic acid (115). Additional intermediate products were identified under various reaction conditions, revealing competing mechanisms in the degradative oxidation of aqueous phenolic aldehydes exposed to O3(g). A unifying mechanism is proposed to explain the production of smaller, less toxic molecules during phenolic aldehyde ozonolysis, enhancing water quality. This mechanism serves as a basis for evaluating the implementation of ozonolysis in scaled-up water treatment processes. 

Previous studies have shown that fats, oils, and greases (FOG) can be deoxygenated to fuel-like hydrocarbons over inexpensive alumina-supported Ni catalysts promoted with Cu or Fe to afford excellent yields of renewable diesel (RD). In this study, supports other than alumina—namely, SiO2-Al2O3, Ce0.8Pr0.2O2, and ZrO2—were investigated to develop catalysts showing improved RD yields and resistance to coke-induced deactivation relative to Al2O3-supported catalysts. Results showed that catalysts supported on Ce0.8Pr0.2O2 and ZrO2 outperformed SiO2-Al2O3-supported formulations, with 20%Ni-5%Fe/ZrO2 affording a quantitative yield of diesel-like hydrocarbons. Notably, the abundance of weak acid sites varied considerably across the different supports, and a moderate concentration of these sites corresponded with the best results. Additionally, temperature-programmed reduction measurements revealed that Ni reduction is greatly dependent on both the identity of the promoter and catalyst support, which can also be invoked to explain catalyst performance since metallic Ni is identified as the likely active site for the deoxygenation reaction. It was also observed that Ce0.8Pr0.2O2 provides high oxygen storage capacity and oxygen mobility/accessibility, which also improves catalyst activity. 

Next-generation polymeric membranes must be derived from more environmentally friendly materials that have similar solubility and miscibility properties as their predecessors to form permeable and selective membranes. Bio-derived polymers, recycled plastics, and eco-friendly solvents have been demonstrated to produce membranes with similar permeability and selectivity as conventional counterparts, though matching membrane durability and cost-effectiveness remain as future research challenges. Slot die coating and 3D printing have been demonstrated to show the scalability of membrane fabrication. Life cycle assessments have become valuable tools in estimating the total environmental impacts of the manufacturing process and characterizing the sustainability of new materials. Recent advances have shortened the gap between materials innovation research and commercial application. 

A novel engineered Ni–Cu/Al₂O₃decarboxylation/decarbonylation catalyst achieved quantitative conversion of brown grease, excellent yield of diesel-like hydrocarbons, effective heteroatom removal, and remarkable resistance to deactivation.