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The morphological properties and particle size characteristics of micro- and nanofibrillated cellulose (NFC) and lignin-containing NFC (LNFC) produced by a microfluidizer processor were investigated. The effects mechanism of lignin-containing on the adsorption of NFC and the stable properties of organic dyes suspension were also studied. The results showed that the preparation process and final performance of NFC were affected by the key factors including lignin, homogenization pressure, and number of homogenization cycles. The increase in the homogeneity of the fibrillated cellulose was minor for the NFC samples, while LNFC samples showed a larger increase in the homogeneity of the particle size distribution. The influence of lignin was reflected both in improved fibrillation efficiency and in the final organic dye dispersion properties achieved by LNFC addition, primarily observed as deceased particle sizes and fibril dimensions. This study indicated that pollution-free dispersion of organic dyes can be realized through the application of lignin-containing NFC.

Cellulose nanowhiskers (CNWs) from plant biomass are of considerable interest, primarily due to their low density, biodegradability, mechanical strength, economic output, and renewability. Here, a new pretreatment method has been developed to produce CNWs based on supercritical CO2 and ethanol. The raw material was micro-fibrillated cellulose (MFC) and experimental factors were controlled to enhance the properties of CNWs produced using a ball-milling technique following supercritical CO2 pretreatment. Cellulose nanofibers (CNFs) were also prepared using a high-pressure Microfluidizer©. A comparative study was conducted of the properties of the raw materials, the CNWs and the CNFs. The solid yields of P-MFC after supercritical CO2 pretreatment gradually decreased, along with the temperature and the reaction time. Scanning electron microscopy (SEM) images of the CNWs and CNFs show that the morphology of the CNWs was basically acicular, while that of the CNFs was mainly soft fibrous. Thermogravimetric analysis results suggest that the thermal stability of the CNWs was substantially higher than those of the CNFs and the raw material. XRD results indicate that the crystallinity showed an initial increasing trend and then declined with increasing temperature and reaction time, and the crystallinity value of CNWs was higher than that of CNFs. The smaller CNWs became rougher and had a larger surface area.

Superhydrophobic surfaces have high potential in self-cleaning and oil-water separation applications. We developed a three-step method for the preparation of superhydrophobic filter paper. It involved citric acid (CA) pretreatment to activate cellulose fibers, coating with cellulose nanofibrils/functionalized silica (CNFs/m-SiO2) slurry to increase surface roughness, and grafting of hexadecyltrimethoxysilane (HDTMS) to enhance water resistance. The water contact angle (WCA) and siding angle (SA) of the prepared filter paper reached 151.5° and 7.5°, respectively. The results showed that, compared to the coated filter paper without the added CNFs, the coated paper with CNFs had higher retention of m-SiO2, thus roughness required for superhydrophobic surface was achieved. Further test under frequent abrasion and acid or alkali conditions showed that CA pretreatment improved the durability of superhydrophobic filter paper due to chemical crosslinking between the modified substrate and m-SiO2. Besides, the prepared superhydrophobic filter paper had outstanding self-cleaning property and high oil-water separation efficiency for various oil-water mixtures. Therefore, it is expected to be used for the treatment of oily wastewater.

Purpose: To determine the antidiabetic, antioxidant and anti-hyperlipidemic effects of aqueous leaf extract of Artemisia argyi (Asteraceae) in alloxan (ALX)-induced diabetic rats. Experimental: Soxhlet apparatus was packed with grinded leaves of A. Argyi and subjected to extraction by double distillation using water as running solvent for 4 – 5 h. Male albino Wistar rats weighing 150 ± 10 g were used in this study. Diabetes was induced in overnight-fasted rats via intraperitoneal administration of freshly prepared 10 % alloxan solution at a dose of 186.9 mg/kg. Serum glucose (Glc), high-density lipoprotein cholesterol (HDL-c), triglycerides (TGs) and total cholesterol (TC) were evaluated using Randox assay kits. Serum reduced glutathione (GSH) was assayed using a slight modification of a previously reproted procedure, while histological examination was carried out microscopically after hematoxylin and eosin staining. Results: Oral administration of aqueous extract of Artemisia argyi significantly reduced ALX-induced increases in glycosylated hemoglobin and blood glucose, but significantly increased total protein, hemoglobin, insulin, and C-peptide levels (p < 0.05). Administration of the extract also led to a significant upsurge in non-enzymic antioxidants i.e. ceruloplasmin, GSH, vitamin E and vitamin C. The extract produced a hypolipidemic effect by significantly reducing total cholesterol (TC) and serum TGs. The hypoglycemic and hypolipidemic effects of the extract were dose-dependent (p < 0.05). Histological examination of the pancreas revealed that the extract protected the integrity of beta cells in ALXinduced diabetic rats. Conclusion: These results indicate the beneficial effects of Artemisia argyi against diabetes mellitus. Thus, Artemisia argyi may be useful in the management of diabetes mellitus. Keywords: Artemisia argyi, Antidiabetic, Glutathione, Histopathology, Antioxidant

It is desirable to develop biodegradable ultraviolet (UV)-shielding materials from renewable resources, as the demand for sustainability is ever increasing. In this work, a novel lignin-TiO2 UV-shielding composite was synthesized successfully via a hydrothermal method induced by nanofibrillated cellulose (NFC). Comprehensive characterization showed that the lignin-TiO2@NFC composite induced by NFC had good nanoparticle size, shape, and thermal stability. The sunscreen performance of lignin-TiO2@NFC was investigated via mixture with unmodified hand cream. The UV-visible (vis) transmission spectra results revealed that the unmodified cream with 10 wt% lignin-TiO2@NFC absorbed approximately 90% of UV light in the full UV band (200 nm to 400 nm), which indicated that lignin-TiO2@NFC had a good UV-shielding ability.

To investigate the high phenolic lignin extraction process, deep eutectic solvents based on oxalic acid and glycerol as a hydrogen bond donor were first prepared and analyzed. Two different types o...

The antioxidant activity of lignin for producing biochemicals has attracted attention. In this paper, a separation method for lignin is proposed, with high-yield and high-antioxidant activity by using a formic acid-catalyzed subcritical ethanol process. The formic acid-catalyzed ethanol lignin (EOL/FA) and ethanol organosolv lignin (EOL) were first prepared using a high-pressure autoclave at different formic acid dosages. Then, the antioxidant activity and the structural and thermal properties of EOL/FA, EOL, alkali lignin, and sodium lignosulfonate were analyzed using antioxidant analysis, Fourier transform infrared (FTIR) spectroscopy analysis, and thermogravimetric analysis (TGA). The phenolic hydroxyl content of the four lignins was also determined by the Folin–Ciocalteau colorimetric method. Results showed EOL/FA had a higher radical scavenging ability and higher total phenolic hydroxyl content than industrial lignin. It indicated that the formic acid-catalyzed subcritical ethanol process was effective for enhancing the antioxidant activity of lignin.

Here, a new pretreatment method has been developed to produce CNFs from micro-fibrillated cellulose (MFC) by supercritical CO 2 pretreatment followed with ball-milling (SCB). MFC was obtained from cotton stalk by chemical purification.Experimental factors were controlled to enhance the properties of SCB-CNF, meanwhile a comparative study was conducted with the method of TEMPO oxidation and microfluid homogenization (TMH). Compared to TMH-CNF, the SCB-CNF has such advantages as Energy saving, high efficiency and environmental protection, indicating a wide application in heat-resistant materials, load materials and other fields. The solid yields of P-MFC after supercritical CO 2 pretreatment gradually decreased together with the temperature and the reaction time. Scanning electron microscope (SEM) images of the SCB-CNF and TMH-CNF show that the morphology of the SCB-CNF was basically acicular but that of the TMH-CNF was mainly soft fibrous. The SCB-CNF is smaller in width and shorter in length, and its size is between CNC and CNF. Thermal gravimetric results suggest that the thermal stability of the SCB-CNF was substantially higher than those of the TMH-CNF. XRD results indicate that the crystallinity showed an initial increasing trend and then declined with increasing temperature and reaction time, and the crystallinity value of SCB-CNF was larger than that of CNFs. The smaller SCB-CNF became rougher and had a larger surface area. High crystallinity make good thermal stability, short and coarse fiber, easier to disperse than CNF, less energy consumption for dispersion, better than 3D mesh. It can be widely used in polymer composites, reinforcing agents, membrane materials and other fields.

To raise H-2/CO and remove tar for biomass product gas, sodium titanates 4Na(2)O center dot 5TiO(2) and Na2O center dot 3TiO(2) were evaluated at 850 degrees C using wood powder pyrolysis gas produced from a 0.3 kg/h screw pyrolyzer with no extra steam, silica sand was selected as an inert material for comparison. The GHSV of the runs were around 2000 h(-1) with tar content of about 200 g/Nm(3). The results suggest that 4Na(2)O center dot 5TiO(2) presents the highest activity, Na2O center dot 3TiO(2) ranks slightly lower, and silica sand shows no activity of enhancing hydrogen yield. The hydrogen formation is promoted through tar cracking, water gas shift and/or methane reforming. The H-2/CO increases to 1.8-2.0, which is higher than that of silica sand (about 0.35) and raw gas (about 0.25). Tar conversion in the 4Na(2)O center dot 5TiO(2) reforming was about 99% and nearly no coke was formed within the test duration of about 8 h, whereas the silica sand was coked obviously in 1 h. Most tar components can be effectively reformed, except for parts of xylene, naphthalene, biphenylene, and anthracene. The activity of 4Na(2)O center dot 5TiO(2) decreases gradually in the long-term test because of the release of sodium and has a tendency to transform to Na2O center dot 3TiO(2), the latter exhibits satisfactory stability and activity. (C) 2017 Elsevier Ltd. All rights reserved.

In order to study the property of lignin-based porous carbon activated by potassium tartrate, the effects of activator types, activator/lignin mass ratio and activation temperature on the surface morphology, specific surface area and pore size distribution of alkali lignin based porous carbon materials were systematically investigated. Meanwhile, the methyl orange adsorption capacity and adsorption kinetics of the lignin-based porous carbon were also evaluated. The N2 adsorption-desorption experiment results showed that the specific surface area value of lignin-based porous carbon materials activated by potassium tartrate (APC-J), KOH (APC-K), and NaOH (APC-Na) are 947, 1113 and 762 m2/g, respectively. Meanwhile, APC-J has a special microporous structure, while the pore structures of APC-K and APC-Na are mainly mesopores. The best specific surface area of lignin-based porous carbon materials was 1911 m2/g obtaining from APC-J-2-8 sample (mass ratio 2:1, activation temperature 800 °C). The adsorption experiment of methyl orange (MO) showed that the adsorption kinetics of APC-J-2-8 conformed to the quasi-second-order kinetic model, mainly chemical adsorption. The isothermal adsorption process conforms to the Langmuir adsorption isothermal adsorption model, which is a single molecular layer adsorption, and the maximum adsorption amounts are 526.31 mg/g.

Objective To determine the synergistic effects of berberine hydrochloride, baicalein, and borneol in different combinations on Candida albicans. Methods The broth microdilution method was used to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the three agents, and the checkerboard method was simultaneously used to determine the MIC and fractional inhibitory concentration index (FICI) of the combination of three antimicrobial agents to study their extracorporeal effects. Results Berberine hydrochloride was the most potent inhibitor of C. albicans (MIC and MBC of 0.160 and 0.640 mg/mL), followed by borneol (MIC and MBC of 0.320 and 0.640 mg/mL) and baicalein (MIC and MBC of 1.28 and 20.48 mg/mL). Moreover, the antifungal effect of the combination was significantly stronger than that tested alone. Further in vivo study showed that the mortality rate of tainted mice reduced over 50% compared with the control group. Conclusion The results of experiments in vitro and in vivo indicate the synergistic effect of the combination of three antimicrobial agents on C. albicans, which can make reference for the future clinical treatment.

The effects of molecular weight on the pyrolysis products properties of alkali lignin were investigated by using thermogravimetric analyzer coupled with Fourier transform infrared spectrometry (TG-FTIR) and tube furnace. Four lignin samples, including pure alkali lignin (AL), more than 10 kDa lignin fraction (AL-10kDa), 5–10 kDa lignin fraction (AL-5kDa) and 1–5 kDa lignin fraction (AL-1kDa) were firstly prepared by ultrafiltration membrane technology. Then the thermal behavior and volatile evolution patterns of the four lignin samples were investigated by TG-FTIR, and the component properties of condensable and incondensable products obtained from tube furnace were characterized by the gas chromatography/mass spectroscopy (GC/MS) and gas chromatography (GC). TG-FTIR results indicated that the molecular weight of lignin was not significantly affected on the evolution temperature ranges and volatile product species, while has an obviously effect on the total yields of CH 4 , CO 2 , phenols and aromatics products. GC/MS and GC results indicated that low molecular weight helps to crack the methoxy groups of lignin leading to the yields of CH 4 , CO, CO 2 , phenol and alkyl phenol increased, while high molecular weight favored the generation of guaiacol and alkyl guaiacol. Meanwhile, the effect of molecular weight on the yields of aromatics was also affected by the pyrolysis temperature.

Straw black liquor is relatively difficult to recover using the Tomlinson process because of the presence of silica in inorganic components. Gasification with direct causticization might serve as a promising alternative; however, the interaction between silica and direct causticization agents needs to be evaluated. In this work, desilication was achieved using a laboratory-scale membrane electrolysis cell adopted from the chlor-alkali industry. Then raw and desilicated straw black liquors were carried out through direct causticization with titanium dioxide (TiO2) and recycled sodium tri-titanate (Na2O center dot 3TiO(2)) at 850 degrees C using a tube furnace. The results show that these two agents exhibit different silica transfer mechanisms. When using TiO2, approximately 80% of the silica is retained in the solid residue after hydrolysis because of chemical interactions. Almost all of the silica transfers to the hydrolysis-derived white liquor when using Na2O center dot 3TiO(2). This means that the process of treating straw black liquor by direct causticization might need additional lime causticization to improve the efficiency of sodium recovery. This observation also indicates that silica will not consume the direct causticization agent Na2O center dot 3TiO(2) after the initial step using TiO2. The sodium hydroxide (NaOH) yield was 60% when using raw black liquor as the feed to the Na2O center dot 3TiO(2) recycling tests and 80% when using desilicated straw black liquor. Considering the NaOH recovered in the electrolysis cell, the total NaOH yields exceed 85% of total titratable alkali. No detectable deterioration of the direct causticization agents was found within the limited number of recycles tested. A greater number of cycles need to be tested at a larger scale to evaluate the feasibility of applying a direct causticization process to straw black liquor.

We presented a three-step method for the preparation of superhydrophobic cellulose filter paper. It involved ZnCl2 pre-treatment to activate the cellulose fibers, a SiO2 sol-gel process to increase surface roughness and grafting of hexadecyl trimethoxysilane groups to chemically enhance the water repellency. The water contact angle of the modified paper reached 154.8°. XRD analysis confirmed silica as the product from the sol-gel process. EDS and SEM analysis showed that pre-treatment results in greater silica adhesion and retention on the paper surface. The modified paper proved to be self-cleaning and resistant to staining. Further tests under various conditions showed that ZnCl2 pre-treatment improved the durability of the superhydrophobic paper. It was concluded that pre-treatment of the filter paper prior to superhydrophobic coating results in a disruption in the cellulose crystalline structure that favours greater silica adhesion and retention.

Depolymerization of lignin is an important step to obtain lignin monomer for the synthesis of functional bio-polymers. In this paper, catalytic degradation/depolymerization of an alkali lignin was investigated in a supercritical ethanol system. The process conditions were optimized in terms of lignin monomer yield, and the liquid products and solid residue were characterized. Results show that the conversion rate of the alkali lignin was improved in both the Ni 7 Au 3 catalyzed and Nickel-catalyzed systems with supercritical ethanol as the solvent. The maximum lignin conversion rate was 69.57% and 68% respectively for the Ni 7 Au 3 and Nickel-based catalysis systems. Gas chromatography/mass spectroscopy (GC/MS) analysis indicated that the catalytic depolymerization products of alkali lignin were mainly monomeric phenolic compounds such as 2-methoxyphenol. The highest yield of 2-methoxyphenol (84.72%) was achieved with Ni 7 Au 3 as the catalyst.

Nanocrystalline cellulose (NCC) has shown great potential for reinforcing nanocomposite systems, particularly in biopolymer-based nanocomposites. In the present work, transparent and biodegradable chitosan (CH)/guar gum (GG)/NCC nanocomposite films were designed and prepared. The effect of NCC loadings on the rheological behavior of the as-prepared nanocomposite suspensions was investigated, the overall properties of the resultant nanocomposite films as a function of various amounts of NCC were determined, and the surface morphology of various nanocomposite films was characterized by scanning electron microscopy (SEM). Results indicated that the increased NCC loadings increased the shear viscosity of the nanocomposite suspensions. Moreover, as expected, the obtained CH/GG/NCC nanocomposite films were found to exhibit improved tensile strength and reduced air permeability in comparison to pure CH/GG films. This work supported the conclusion that NCC was effective in reinforcing the CH/GG composite films, which may be a promising material for food packaging applications.

Due to its amazing physicochemical properties and high environmental compatibility, cellulose nano-crystals (CNC) hold great promise for serving as a strategic platform for sustainable development. Now, there has been growing interest in the development of processes using waste or residual biomass as CNC source for addressing economic and environmental concerns. In the present work, a combined process involving phosphoric acid hydrolysis, enzymatic hydrolysis and sonication was proposed aiming to efficiently exact CNC from low-cost old corrugated container (OCC) pulp fiber. The effect of enzymatic hydrolysis on the yield and microstructure of resulting CNC was highlighted. Results showed that the enzymatic hydrolysis was effective in enhancing CNC yield after phosphoric acid hydrolysis. CNC was obtained with a yield of 23.98 wt% via the combined process with phosphoric acid concentration of 60 wt%, cellulase dosage of 2 mL (84 EGU) per 2g fiber and sonication intensity of 200 W. Moreover, the presence of enzymatic hydrolysis imparted the obtained CNC with improved dispersion, increased crystallinity and thermal stability.

2,5-Bis-(hydroxymethyl)furan (BHMF) is an important biomass-based platform chemical that can be derived from the hydrogenation of biomass-based 5-hydroxymethylfurfural (HMF). In this paper, the formation of BHMF from HMF via the catalytic transfer hydrogenation (CTH) process, using isopropanol as the hydrogen source and Ru/Co3O4 as the catalyst, was studied. The results revealed that the Ru/Co3O4 catalyst displayed a high catalytic efficiency, and that a BHMF yield of up to 82% was obtained at 190 °C in 6 h. Moreover, it was found that the recovered Ru/Co3O4 exhibited a similar catalytic activity to the pristine Ru/Co3O4 catalyst. These results supported the conclusion that the present CTH process is an attractive green route for the synthesis of BHMF from biomass-based HMF.

The effects of Na as organic bound form or as inorganic salts form on the pyrolysis products characteristics of alkali lignin were investigated by using thermogravimetric analyzer coupled with Fourier transform infrared spectrometry (TG-FTIR), tube furnace and thermo-gravimetric analyzer (TGA). Results of TG-FTIR and tube furnace indicated that the two chemical forms Na reduced the releasing peak temperature of CO and phenols leading to the peak temperature of the maximum mass loss rate shifted to low temperature zone. Furthermore, organic bound Na obviously improved the elimination of alkyl substituent leading to the yields of phenol and guaiacol increased, while inorganic Na increased the elimination of phenolic hydroxyl groups promoting the formation of ethers. It was also found the two chemical forms Na had different effects on the gasification reactivity of chars. For inorganic Na, the char conversion decreased with increasing the char forming temperature, while organic bound Na was opposite.

Polyaniline (PANI)/graphene oxide (GO) composites were synthesized via in situ polymerization of aniline in the presence of GO. The effect of microwave treatment of graphite on the electrical conductivity and electrochemical properties of PANI/GO composites was highlighted, and the morphology and microstructure were subsequently characterized using transmission electron microscopy, scanning electron microscopy, Fourier-transformed infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis. The results demonstrated that microwave treatment of graphite imparted a well-dispersed, highly ordered layered structure to the as-prepared GO, and in turn facilitated strong bonding between the GO and PANI nanosheets, which may be responsible for the improved electrical conductivity and electrochemical properties of the resulting PANI/GO composites. The desired PANI/GO composites possessed an electrical conductivity of 508 S/m, an areal capacitance of 172.8 mF/cm2, and a retained capacitance of 87.4% after cycling, representing percentage increases of 102, 232, and 112, respectively, as a result of the microwave treatment of graphite. The resulting composites are promising electrode materials for high-performance and ecofriendly electrical energy storage devices.

Incorporation of nanofillers into a polymeric matrix has received much attention as a route to reinforced polymer nanocomposites. In the present work, an environmentally friendly chitosan (CTS)/titanium dioxide (TiO2) nanocomposite coating was designed/prepared and subsequently employed for imparting antibacterium and improved mechanical properties to cellulosic paper via surface coating. Effect of TiO2 nanoparticle loadings on the rheological behavior of nanocomposite coatings was investigated. Surface application of CTS/TiO2 nanocomposite coatings to cellulosic paper was performed, and the antibacterial activity and mechanical properties of surface-coated cellulosic paper were examined. Results showed that the increased TiO2 nanoparticle loadings decreased the viscosity and dynamic viscoelasticity of the as-prepared coatings, and improved the antibacterial activity and mechanical properties of surface-coated cellulosic paper. The optimum loading of TiO2 nanoparticles was identified at 10%. This work suggested that CTS/TiO2 nanocomposite coatings may have the potential to be used as a promising antibacterial protective coating for paper packaging.

Cellulose is the most abundant renewable polymer in the nature, and cellulosic paper is widely used in our daily life. Conferring electroconductivity to cellulosic paper would allow this conventional material to hold great promise for a wide range of energy-related applications. In the present work, multi-walled carbon nanotube (MWCNT)/polyaniline (PANI) nanocomposites were synthesized via in situ oxidation polymerization process and characterized by FT-IR and TEM. Subsequently, the application of the synthesized MWCNT/PANI nanocomposites as a wet-end filler for the production of electro-conductive paper was demonstrated/developed. Results showed that the cellulosic paper was imparted with an electro-conductivity of up to 0.14 S·m -1 while exhibiting a pronounced improvement in mechanical properties as a function of the added MWCNT/PANI nanocomposites.

The interest in utilization of alkali lignin in black liquor by pyrolysis and gasification is increasing due to the wish to produce bio-fuel and bio-chemical. Besides alkali lignin, the sodium salts are also the basic component of black liquor; they exist in two main forms: as phenolic sodium ( CONa) and carboxylate sodium ( COONa) groups forming a part of alkali lignin or as dissolved salts (NaOH and Na 2 CO 3 ). In this paper, the influences of these dissolved salts on the pyrolysis and gasification characteristics of alkali lignin were discussed. Five lignin samples, including pure acid precipitated lignin, 10% and 60% NaOH-loaded lignin, 10% and 60% Na 2 CO 3 -loaded lignin, and black liquor solids were selected as the testing samples. Following experimental research on the evolution patterns of volatile products were carried out on a thermogravimetric analyzer coupled with Fourier transform infrared spectrometry. The experimental data indicated that the pyrolysis and gasification reaction of alkali lignin could be catalyzed by NaOH and Na 2 CO 3 . In the pyrolysis stage, the maximum mass loss rate decreased with increasing amount of NaOH and Na 2 CO 3 additives, while in the gasification stage it increased. In the gasification stage, the temperature of the maximum mass loss rate shifted to lower value with increasing amount of NaOH and Na 2 CO 3 additives, but did not significantly change in the pyrolysis stage. FTIR analysis showed that the influences of NaOH and Na 2 CO 3 additives on the pyrolysis and gasification products mainly varied in amounts but not in species. FTIR results also suggested that the release time of the volatile was affected by increasing NaOH and Na 2 CO 3 additives amount. Moreover, NaOH and Na 2 CO 3 markedly improved the evolution of CO in the gasification stage.

CO2 gasification of the reed (Phragmites australis) kraft black liquor (KBL) and its water-soluble lignin (WSL) was analyzed by thermogravimetry coupled with Fourier transform infrared spectrometry (TG–FTIR). In KBL gasification, major mass loss of KBL occurred between 150 and 1000 °C, followed by a further slow mass loss until the heating was stopped and the TG curve leveled off. The TG profiles of the WSL and the KBL were similar during gasification; however, the differential thermogravimetry (DTG) curves and mass decrease from 300 °C of the TG curves of the WSL and the KBL were different because of their dissimilar ingredients. The CO formation mechanism was the same and independent of structural types of lignins between reed and wood in their KBL CO2 gasification.