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Mountain pine beetle killed Lodgepolepine (Pinus contortaDouglas ex Loudon) wood chipswere pretreated using an acidic sulfitesolution of approximately pH = 2.0 at a liquor to wood ratio of 3and sodium bisulfite loading of 8 wt % on wood. The combined hydrolysisfactor (CHF), formulated from reaction kinetics, was used to designa scale-up pretreatment on 2000 g wood chips at a relatively low temperatureof 165 °C that reduced furan formation and facilitated high solidssaccharification and fermentation. The pretreated solids and liquorwere disk milled together to result in a biomass whole slurry of 25%total solids. The whole biomass slurry was directly used to conductsimultaneous enzymatic saccharification and combined fermentation(SSCombF) using a commercial cellulase and Saccharomyces cerevisiaeYRH400 without detoxification. A terminal ethanol titer of 47.1g L–1with a yield of 306 L (tonne wood)−1, or 72.0% theoretical, was achieved when SSCombF was conducted atan unwashed solids loading of 18%. The lignosulfonate (LS) from SPORLwas highly sulfonated and showed better dispersibility than a highpurity commercial softwood LS, and therefore has potential as a directlymarketable coproduct. [ABSTRACT FROM AUTHOR]

The direct preparation of adsorption materials from black liquor (BL) produced by the kraft pulping process has great potential in wastewater treatment. A three-dimensional nitrogen-doped porous carbon (N-BLSAC) with high specific surface area and large pore volume was synthesized. The adsorption performance of N-BLSAC for Cr(VI) and tetracycline (TC) was systematically investigated. Compared with the porous carbon prepared from purified lignin (N-PLAC), the adsorption performance of N-BLSAC for TC was more superior. It was not only attributed to the pore-filling effect but also the electrostatic interaction, hydrogen bonding, and π-π electron-donor-receptor. In terms of Cr(VI), the adsorption performance of N-BLSAC and N-PLAC had little difference. Moreover, N-BLSAC and N-PLAC exhibited an excellent anti-interference property. Therefore, the porous carbon prepared by direct carbonization of BL has significant advantages in removing Cr(VI) and TC from aqueous solution. [Display omitted] • Black liquor was directly used to prepare high surface area activated carbon (N-BLSAC). • The lignin-based porous carbon (N-PLAC) was also prepared for comparison. • The adsorption performance of N-BLSAC was superior to N-PLAC. • The adsorption mechanism of Cr(VI) and TC on N-BLSAC was proposed. [ABSTRACT FROM AUTHOR]

Thisstudy conducted an investigation of the effect of lignosulfonate(LS) on enzymatic saccharification of lignocelluloses. Two commercialLSs and one laboratory sulfonated kraft lignin were applied to Whatmanpaper, dilute acid and SPORL (sulfite pretreatment to overcome recalcitranceof lignocelluloses) pretreated aspen, and kraft alkaline and SPORLpretreated lodgepole pine. All three lignin samples inhibited cellulosesaccharification of Whatman paper, but enhanced the saccharificationof the four lignocellulosic substrates. The level of enhancement wasrelated to the molecular weight and degree of sulfonation of the ligninas well as the substrate lignin structure. When different molecularweight (MW) fractions of one commercial LS (SXP), generated from sulfitepulping of hardwood, were applied to the Whatman paper, the largeMW fraction (SXP1) with the lowest degree of sulfonation inhibitedcellulose saccharification while the intermediate (SXP2) and smallest(SXP3) MW fractions enhanced saccharification. All MW fractions enhancedsaccharification of the four lignocellulosic substrates with maximalenhancement by the smallest MW fraction, SXP3. The enhancement wasmost significant for the kraft lodgepole pine substrate and leastsignificant for the SPORL pretreated lodgepole pine using all threeLS and SXP fractions. The results suggest that LS acts as a surfactantto enhance pure cellullose saccharification. When LS is applied tolignocelluloses, it acts as a surfactant to block bound lignin frombinding cellulase nonproductively leading to enhanced saccharification. [ABSTRACT FROM AUTHOR]

• The HTC of BLS was conducted under different conditions and solvents. • The maximum bio-oil yield from HTC of BLS achieved at 53.4%. • The phenols in BLS bio-oil were mainly H-type. • BLS char showed excellent Cr(VI) adsorption performance. The hydrothermal conversion (HTC) of black liquor solid (BLS) was investigated for producing phenolics and hydrochar. For comparison, the precipitated lignin (PL) was also investigated. The HTC experiments were conducted under different temperatures, holding times and reaction solvents to examine the optimum conditions for producing bio-oil. The maximum bio-oil yield of BLS of 53.3% was achieved at 50 wt% ethyl acetate/water cosolvent under 300 °C for 30 min. For PL, it was 86.7% at 50 wt% ethanol/water cosolvent under 300 °C for 30 min. GC–MS analysis showed that phenolics were the main products in bio-oil. The phenolics obtained from PL HTC were mainly S-type, followed by G-type; while H-type phenols were the main products in bio-oil from BLS. The hydrochar was characterized by FT-IR, BET and SEM. Moreover, the adsorption performance for Cr(VI) was investigated, which indicated that hydrochar from BLS was a promising candidate for heavy metals adsorption. [ABSTRACT FROM AUTHOR]

An environmentally friendly lignin-based composite (Lignin-PEI) was facilely prepared via cross-linking enzymatic hydrolysis lignin matrix and branched poly (ethylene imine). The specific physicochemical and structural properties of lignin-PEI were characterized by elemental analysis, N 2 physisorption, GPC, TG, SEM, FT-IR and XPS. The nitrogen content of lignin-PEI was 9.02%, and the BET surface area was 20.32 m2/g. The synthetic composite showed high capacity and selectivity of Cr(VI) adsorption. The influence of solution pH, contact time, initial Cr(VI) concentration, and coexisting ions on Cr(VI) adsorption on lignin-PEI was systemically studied. The Cr(VI) adsorption on lignin-PEI was well described by the Langmuir model. According to the Langmuir model, the Cr(VI) adsorption capacity on lignin-PEI was as high as 898.2 mg/g at 318 K and pH 2.0. The calculated thermodynamic parameters, such as Δ G , Δ H , and Δ S , indicated the spontaneous and endothermic adsorption of Cr(VI) on lignin-PEI. The adsorption of Cr(VI) by lignin-PEI was following the pseudo-second-order kinetic model, indicating that it was a chemisorption process. The uptake mechanism was demonstrated to be electrostatic attraction, ion exchange, complexation and partial reduction. This work provided a promising candidate for Cr(VI) uptake with lignin-based biosorbents. Unlabelled Image • An eco-friendly lignin-based biosorbent was prepared by grafting PEI. • The maximum adsorption capacity of Cr(VI) was 898.2 mg/g. • Lignin-PEI had an excellent selectivity for Cr(VI). • The adsorption mechanism was proposed. [ABSTRACT FROM AUTHOR]

A novel and practical co-precipitation process in an aqueous medium was developed to prepare lignin-based silica composite submicron particles from chemical modified alkali lignin and sodium silicate by a high-value-added application strategy of lignin. The alkali lignin was first modified by phosphorylation reaction using sodium 3-chloro-2-hydroxypropyl phosphate as a modifier. The phosphorylated alkali lignin named sodium lignin phosphate (SLP) was added to silica matrix as a co-precipitant and dispersant to prepare lignin-based silica composite particles (SLP-SiO 2 ) via the hydrogen bonding interaction between the hydroxyl groups in lignin and silica. The weight ratio of lignin to silica reached 1.33. SEM, BET and XPS analyses indicated that lignin mainly deposited on the surface and pores of silica to increase the surface hydrophobicity. The average diameter of the SLP-SiO 2 was about 300 ∼ 400 nm. With the increase of lignin incorporated onto the silica matrix, the BET surface area decreased from 385.6 to 54.8 m 2 g −1 . Results of the study were of practical importance in high-value-added application of lignin. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pyrolysis characteristics and product distribution of BLS were studied. • The activation energy of BLS was higher than that of lignin. • The aromatic hydrocarbon content of BLS through down tube reactor pyrolysis was 90.15%. • The inorganic salt in BLS promoted the removal of phenolic hydroxyl groups. • The mechanism of bond breaking during PL pyrolysis was proposed. In this study, the pyrolysis behaviors, kinetics and product distribution of black liquor solid (BLS) and precipitated lignin (PL) were studied by TGA, Py-GC/MS and a homemade down tube reactor. Compared with PL, the pyrolysis process of BLS was more complex and the residue was lower based on TG/DTG analysis. The average activation energy of BLS (440 ~ 456 KJ/mol) calculated by three model-free methods were higher than that of PL (293 ~ 339 KJ/mol). Py-GC/MS analysis showed that the total content of aromatic monomers in BLS bio-oil products was 26.02 ~ 26.50% (750 ~ 850 °C), while it was 57.86 ~ 66.58% in PL bio-oil products. Moreover, BLS obtained a maximum aromatic hydrocarbon content of 90.15% (950 °C) through down tube reactor pyrolysis, while it was 81.38% for PL. The alkali catalysis of the inorganic salt in BLS promoted the removal of phenolic hydroxyl groups. [ABSTRACT FROM AUTHOR]

• A novel betaine-amino acid based NDES was prepared at room temperature. • [Bet][AA] NDES showed excellent lignin and xylan solubility. • MCC and corncob showed enhanced glucose yield after pretreatment. • The mechanism of [Bet][AA] NDES pretreatment was proposed. A novel natural deep eutectic solvent (NDES) with water content ranging from 65 to 93 wt%, in which betaine (Bet) acts as the cation and amino acids (AAs) as the anions, was prepared by a simple and green chemical route. [Bet][AA] NDES showed excellent xylan and lignin solubility, however, scare cellulose solubility. A mild and facile pretreatment process with [Bet][AA] NDES was carried out at 60 °C for 5 h. The enzymatic hydrolysis efficiency of cellulose and corncob was significantly improved. Detailed characterization showed that the enhancement of cellulose digestibility derived mainly from xylan and lignin removal. Xylan and lignin removal for [Bet][Lys]-W87 was 47.68 and 49.06%, while it was 42.20% and 57.01% for [Bet][Arg]-W82, respectively. FT-IR, SEM, XRD, and HSQC NMR studies confirmed the effectiveness and mechanism of [Bet][Lys]-W87 and [Bet][Arg]-W82 on biomass pretreatment. [ABSTRACT FROM AUTHOR]

• Highly stretchable hydrogel was prepared from biomass lignin. • LCP hydrogel performed excellent viscoelasticity and stretchability. • Compared with PVA hydrogel, the elongation rate of LCP increased by 20 times. • LCP hydrogel showed good thermosensitivity and electrical conductivity. In this study, hydroxyethyl cellulose (HEC) and polyvinyl alcohol (PVA) as the framework, borax as the cross-linker, and biomass lignin from pulping black liquors and biorefinery as the plasticizer were used to synthesize the lignin-based HEC-PVA (LCP) self-healing conductive hydrogel with highly stretchable and thermosensitive properties by the one-step fabrication method. Compared with the PVA hydrogel, the maximum storage modulus and the elongation rate was increased by 7 times and 20 times, respectively. Uniformly distributed lignin could increase the mobility and distance of polymer molecular chains, therefore improve the viscoelasticity and stretchability of the LCP self-healing hydrogel. The LCP hydrogel could recover to the original state in 12 s after 10000% shear strain for 4 cycles. The LCP hydrogel also presented good thermosensitivity and electrical conductivity, and were very promising for applications in the fields of 3D printing and wearable electronic devices, that broadened the efficient utilization of biorefinery lignin. [ABSTRACT FROM AUTHOR]