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Microwave-assisted catalytic solvolysis of lignin in formic acid was studied concerning the addition of HUSY catalysts modified by oxalic acid. Characteristics of the modified catalysts were examined by XRD, NH 3 -TPD and BET. The highest yield of liquid product was achieved as 88.28 wt% (aromatic monomer fraction as bio-oil 1 of 15.36% and oligomer fraction as bio-oil 2 of 67.52%) with the addition of HUSY modified by 0.2 mol/L oxalic acid (HUSY-0.2 M). The production of aromatic monomers in bio-oil 1 identified by GC/MS was enhanced with the addition of HUSY catalysts regardless of acidic treatment, and achieved the maximum value for HUSY-0.2 M experiment. Aromatic oligomers with molecular weight of 328, 342, 358, 378, 394, 424 and 454 were characterized by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) analysis. Formation of almost all identified oligomers was promoted with catalytic experiments with HUSYs except that of 328, extent of which is significantly determined by the pore size, Si/Al ratio and acidic site distribution of the modified catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • PSSG was supported by cellulose-based scaffold via top-down and bottom-up methods. • CS was prepared by removing lignin and hemicellulose from wood to encapsule PSSG. • CNF was used as nanofiller to support and strengthen PSSG to prevent its cold flow. • Rigid PSSG@CS shows outstanding mechanical & impact-resistance properties. • PSSG@CNF as impact-resistance gel is flexible, self-healable, and adhesive. Shear stiffening gel (SSG) is a promising cushioning material for impact-resistant applications as its moduli significantly increase under shear. However, SSG cannot retain its shape due to cold flow effect, which severely restricts its broad applications. In this study, both "top-down" and "bottom-up" strategies were respectively employed to construct cellulose supported and strengthened polyborosiloxane SSG (PSSG), resulting in stable shapes with significantly enhanced mechanical properties and impact-resistant performance attributed to reinforced concrete-like "steel-and-cement" structure. In "top-down" strategy, porous cellulose scaffolds (CS) were fabricated by removing lignin and hemicellulose from wood and then used as templates to encapsulate PSSG (PSSG@CS). In "bottom-up" strategy, cellulose nanofibers (CNFs) were well dispersed in PSSG and employed as nanofillers to strengthen PSSG (PSSG@CNF). Both PSSG@CS and PSSG@CNF effectively inhibited the cold flow deformation of PSSG and exhibited significantly enhanced shear stiffening properties. Rigid and hydrophobic PSSG@CS with fixed shape inherits the excellent mechanical properties of wood, with maximum storage modulus of 908 MPa, much higher than PSSG@CNF (15.3 MPa) and pristine PSSG (4.7 MPa). PSSG@CNF is flexible, self-healable, and adhesive, and could be processed to varied shapes. Both PSSG@CS and PSSG@CNF displayed outstanding impact-resistant performance when employed as protective cushion for glass. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nearly 93% of N, 97% of P, 99% of K, and 80% of water were recovered by TAP-MD system. • The TAP pretreatment improves separation efficiency of MD process. • The TAP pretreatment inhibits membrane fouling in MD treatment. • Urine stabilization is achieved by TAP process and further enhanced by MD treatment. • The TAP-MD system has better performance on thermal efficiency and energy consumption. Membrane distillation (MD) has been applied to urine recovery with growing interest and demand for resource recovery from waste. However, MD application to urine is limited by obstacles, including the inability to recover nutrients and water simultaneously, low separation efficiency due to ammonia permeation, and membrane fouling. Herein, a novel system integrating thermally activated peroxydisulfate with MD (TAP-MD) was developed to overcome the above obstacles. The synergy effects were found between TAP pretreatment and MD process. With TAP pretreatment, membrane fouling was alleviated by organics degradation and mineral precipitation reduction, resulting in significant improvements in MD performance. Water flux of pretreated urine decreased from 25 L/m2/h to 15 L/m2/h after 80 % of water recovery, but that of unpretreated urine decreased to near zero after 38 % of water recovery. Meanwhile, MD process revealed further enhancement in urine stability by activating residual peroxydisulfate, reducing nutrient losses due to ammonia volatilization during storage and utilization of concentrated fertilizer. As a result, nearly 92.95 % of N -urea, 97.35 % of P, and 99.77 % of K was recovered as concentrated liquid fertilizer, meanwhile, 80 % of water was recovered as high-quality reclaimed water. The energy efficiency was improved by reusing waste heat from pretreatment. The TAP-MD system achieved a 45.63 % increase in thermal efficiency and a 38.25 % reduction in specific energy consumption compared to no pretreatment. This study developed an energy-efficient and high-performance separation treatment for complete resource recovery from urine. [ABSTRACT FROM AUTHOR]