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Grzegorz Milczarek - One of the best experts on this subject based on the ideXlab platform.
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the effect of silver salts and Lignosulfonates in the synthesis of lignosulfonate stabilized silver nanoparticles
Journal of Molecular Liquids, 2017Co-Authors: Anna Modrzejewskasikorska, Emilia Konowal, Teofil Jesionowski, Adam Cichy, Marek Nowicki, Grzegorz MilczarekAbstract:Abstract Water-soluble lignin derivatives – technical Lignosulfonates (LS) – were used as reducing and stabilizing agents for a simple synthesis of silver nanoparticles (LS-AgNPs) in aqueous solution at room temperature during the reaction with silver salt. Three salts were used as the metal precursor: AgClO4, AgBF4 and CH3C6H4SO3Ag. The obtained silver colloids were analyzed by UV–Vis spectrophotometry, particle size distribution (NIBS method), transmission electron microscopy (TEM) and atomic force microscopy (AFM). Both the origin of the biomacromolecule and the type of silver salt contribute to the final size and shape of the LS-AgNPs. Therefore the selection of different reagents can be used to control the AgNPs size. As a possible application, the obtained silver particles were studied for their catalytic activity in the reduction of three dyes – C.I. Basic Blue 9 (methylene blue), C.I. Basic Violet 10 (rhodamine B) and C.I. Basic Orange 14 (acridine orange) – by sodium borohydride.
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Preparation of Manganese Lignosulfonate and Its Application as the Precursor of Nanostructured MnOx for Oxidative Electrocatalysis
MDPI AG, 2017Co-Authors: Klaudia Gawluk, Anna Modrzejwska-sikorska, Tomasz Rębiś, Grzegorz MilczarekAbstract:The synthesis of manganese Lignosulfonates by a two-step method has been reported. It was based on the conversion of technical sodium derivative of lignosulfonate to its hydrogen form i.e., lignosulfonic acid and its further reaction with manganese hydroxide. The obtained product was electroactive, and could be applied as the precursor of electroactive manganese oxide. The product showed a reversible redox activity in the potential range of 0 to 1 V vs. an Ag/AgCl reference electrode. The electroactivity of the obtained product can be tentatively assigned to the redox activity of both the electrodeposited MnOx and the presence of lignosulfonate-derived quinones since the energy dispersive spectroscopy (EDS) confirmed the presence of organic matter in the deposit. It also showed substantial electrocatalytic activity towards the anodic oxidation of hydrogen peroxide. This suggests that manganese Lignosulfonates could be a valuable compound for the electrochemical preparation of electroactive layers that are suitable in the development of electrochemical sensors
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synthesis and multifunctional properties of lignosulfonate stabilized gold nanoparticles
Materials Letters, 2015Co-Authors: Emilia Konowal, Anna Modrzejewskasikorska, Grzegorz MilczarekAbstract:Abstract Various technical Lignosulfonates (LSs) were used as reducing and stabilizing agents for a novel one-step synthesis of gold nanoparticles (LS–AuNPs) in aqueous solution at room temperature. As a result, stable colloids of LS–AuNPs are formed during the reaction with the particle size being the function of the LS type. The obtained LS–AuNPs were characterized by UV–vis spectrophotometry, size distribution (DLS) and transmission electron microscopy (TEM). The resulting gold colloids can be used for different purposes, e.g. as chemical probes for the presence of heavy metals, as signal amplifiers in surface enhanced Raman spectroscopy (SERS) or as electrocatalysts as evidenced by preliminary cyclic voltammetry study (CV). The obtained results clearly indicate the possibility of low-cost production of large quantities of colloidal gold–lignosulfonate nanoparticles using waste materials derived from renewable sources.
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one step synthesis of lignosulfonate stabilized silver nanoparticles
Colloids and Surfaces B: Biointerfaces, 2013Co-Authors: Grzegorz Milczarek, Tomasz Rebis, Justyna FabianskaAbstract:Abstract Softwood lignosulfonate (SLS) was used as a reducing agent for one-step synthesis of silver nanoparticles (SLS-AgNPs) in an aqueous solution at room temperature. In this reaction SLS acts also as a stabilizing agent and as a result, stable colloids of silver nanoparticles are formed during the reaction with the average particle size of 41 nm. The obtained SLS-AgNPs were characterized by UV–vis spectrophotometry, size distribution and AFM imaging after casting on mica. Due to metal ion complexing capability of Lignosulfonates, the SLS-AgNPs appeared to be capable of colorimetric detection of metal ions (especially nickel). Additionally, the SLS-AgNPs could be assembled into thin films on conducting substrates (ITO glass) using electrophoretic deposition. XPS spectroscopy was used to characterize such films and revealed a strong interaction of silver atoms with some carbon atoms of the SLS.
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The effect of Lignosulfonates as electrolyte additives on the electrochemical performance of supercapacitors
Electrochemistry Communications, 2011Co-Authors: Grzegorz Lota, Grzegorz MilczarekAbstract:Abstract Two types of carbonaceous materials of different specific surface areas (835 and 1901 m 2 g −1 ) were used as electrode materials in electrochemical capacitors and their performance was investigated in 1 mol L −1 H 2 SO 4 with and without addition of two Lignosulfonates of different molecular masses (8000 and 42,700 g mol −1 ). Measurements of 2-electrode cells confirmed that Lignosulfonates as electrolyte additives increase the overall capacity of the supercapacitor of up to 33%. Moreover, for the electrolyte with Lignosulfonates the charge propagation was facilitated, implying its capability of working at heavy duty regimes. Cycleability tests confirmed the absence of any significant effect of lignosulfonate additions to the electrolyte on supercapacitor durability. The relative capacitance change after 5000 cycles of galvanostatic charge/discharge at 1 A g −1 was ca. + 4.5% for less porous carbon and − 4.2% for more porous carbon, respectively. Furthermore, the investigations carried out in a 3-electrode configuration proved that a lignosulfonate addition to the electrolyte gives rise to the development of a reversible redox system on the positive electrode, due to the deposition of a thin lignosulfonate-derived film showing substantial redox activity assignable to quinone-type moieties.
Mingsong Zhou - One of the best experts on this subject based on the ideXlab platform.
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Influence of Lignosulfonates on the Stability of Dimethomorph Water Based Suspension
Advanced Materials Research, 2012Co-Authors: Yu Xia Pang, Ting Zhou, Mingsong ZhouAbstract:The dispersive effect of four Lignosulfonates (Kinsperse126, sodium lignosulfonate, magnesium lignosulfonate and a modified lignosulfonate GCL4-1) on the stability of Dimethomorph (DMM) water based suspension with different particle sizes was investigated. DMM suspension without dispersant was unstable owing to the strong aggregation of particles, while the stability was increased after the addition of lignosulfonate (LS), which can be adsorbed on the particle surface and weaken the aggregation of particles. Moreover, the higher sulfonated degree of LS, the better the dispersible ability was. Compared with LS of high sulfonated degree which could improve the zeta potential of DMM, LS with high molecular weight had larger adsorption capacity and steric effect on the pesticide particles. Associated with the dispersive behavior of DMM suspension, the electrostatic repulsion was found to be the more important factor impacting the stability of DMM suspension by comparison with the steric effect.
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properties of sodium lignosulfonate as dispersant of coal water slurry
Energy Conversion and Management, 2007Co-Authors: Dongjie Yang, Mingsong ZhouAbstract:In order to use Lignosulfonates (a by-product of pulp and paper processes) as an effective dispersant of coal water slurry five purified sodium lignosulfonate (SL) samples with different molecular weights were prepared by fractionation using ultrafiltration and dialysis. The effect of SL on the apparent viscosity of coal water slurry (CWS) was investigated. The adsorption behavior of the SL on the coal water interface has much greater effect on the viscosity of coal water slurry. The higher adsorption amount and compact adsorption film of SL on the coal surface help reduce the viscosity of CWS, and the zeta potential is also an important factor, which is influenced by the sulfonic and carboxyl group contents of the lignosulfonate molecule. Furthermore, the SL with its molecular weight ranging from 10,000 to 30,000 has both a higher adsorbed amount and zeta potential on the coal surface and the best effect on reducing the viscosity of the coal water slurry.
Nicholas J Westwood - One of the best experts on this subject based on the ideXlab platform.
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use of bisulfite processing to generate high β o 4 content water soluble Lignosulfonates
ACS Sustainable Chemistry & Engineering, 2017Co-Authors: Daniel M Milesbarrett, James R D Montgomery, Christopher S Lancefield, David B Cordes, Alexandra M Z Slawin, Tomas Lebl, Reuben Carr, Nicholas J WestwoodAbstract:With lignin-first biorefineries likely to become a reality, controlled depolymerization of high-quality lignin streams to high-value products has become a priority. Using bisulfite chemistry, access to a high-β-O-4 content water-soluble lignosulfonate has been achieved, allowing follow-up procedures in water to be conducted. We show that phenolic β-O-4 units preferentially react under acidic bisulfite conditions, while nonphenolic β-O-4 units react much more slowly. Exploiting this improved chemical understanding and inherent selectivity, we have prepared a softwood lignosulfonate in which phenolic β-O-4 α-sulfonation has occurred, leaving significant native β-O-4 content. Use of an O-benzoylation protocol with lignin coupled with advanced two-dimensional nuclear magnetic resonance methods has allowed detailed analysis of this and other commercial and industrial Lignosulfonates. Conversion of the native β-O-4 to benzylic, oxidized β-O-4 units was followed by a selective reductive cleavage to give a premiu...
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Use of Bisulfite Processing To Generate High-β-O‑4 Content Water-Soluble Lignosulfonates
2017Co-Authors: Daniel M. Miles-barrett, James R D Montgomery, Christopher S Lancefield, David B Cordes, Alexandra M Z Slawin, Tomas Lebl, Reuben Carr, Nicholas J WestwoodAbstract:With lignin-first biorefineries likely to become a reality, controlled depolymerization of high-quality lignin streams to high-value products has become a priority. Using bisulfite chemistry, access to a high-β-O-4 content water-soluble lignosulfonate has been achieved, allowing follow-up procedures in water to be conducted. We show that phenolic β-O-4 units preferentially react under acidic bisulfite conditions, while nonphenolic β-O-4 units react much more slowly. Exploiting this improved chemical understanding and inherent selectivity, we have prepared a softwood lignosulfonate in which phenolic β-O-4 α-sulfonation has occurred, leaving significant native β-O-4 content. Use of an O-benzoylation protocol with lignin coupled with advanced two-dimensional nuclear magnetic resonance methods has allowed detailed analysis of this and other commercial and industrial Lignosulfonates. Conversion of the native β-O-4 to benzylic, oxidized β-O-4 units was followed by a selective reductive cleavage to give a premium aromatic monomer in pure form
Alessandro Piccolo - One of the best experts on this subject based on the ideXlab platform.
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replacing calcium with ammonium counterion in Lignosulfonates from paper mills affects their molecular properties and bioactivity
Science of The Total Environment, 2018Co-Authors: Davide Savy, Vincenza Cozzolino, Marios Drosos, Pierluigi Mazzei, Alessandro PiccoloAbstract:Abstract Lignosulfonates are important by-products of the paper industry and may be transformed into different commodities. We studied the molecular properties of ammonium (LS-AM) and calcium Lignosulfonates (LS-C) and evaluated their bioactivity towards the early development of maize plantlets. The FT-IR, 13 C NMR and 1 H- 13 C-HSQC-NMR spectra showed that the two Lignosulfonates varied in hydroxyl, sulfonate and phenolic content, while DOSY-NMR spectroscopy suggested a similar diffusivity. High Performance Size Exclusion Chromatography (HPSEC) was used to simulate the effects of root-exuded acids and describe the conformational dynamics of both LS substrates in acidic aqueous solutions. This technique showed that LS-C was stabilized by the divalent Ca 2+ counterion, thus showing a greater conformational stability than LS-AM, whose components could not be as efficiently aggregated by the monovalent NH4 + counter-ion. The plant bioassays revealed that LS-AM enhanced the elongation of the root system, whereas LS-C significantly increased both total and shoot plant weights. We concluded that the lignosulfonate bioactivity on plant growth depended on the applied concentrations, their molecular properties and conformational stability.
Dongjie Yang - One of the best experts on this subject based on the ideXlab platform.
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biorefinery Lignosulfonates as a dispersant for coal water slurry
Sustainable Chemical Processes, 2016Co-Authors: Dongjie Yang, Yanlin Qin, Wenlong Xiong, J Y ZhuAbstract:Valorization of lignin from biofuel production is the key to developing biorefinery technologies for sustainable and economic utilization of lignocellulosic biomass. Here we present isolating lignosulfonate from the spent liquors of Sulfite Pretreatment to Overcome the Recalcitrance of Lignocelluloses (SPORL)-pretreated lodgepole pine and Douglas-fir forest residue as a dispersant for coal water slurry. The two SPORL pretreatments were conducted at a pilot scale and resulted in very high ethanol yield from the pretreated biomass. Therefore, demonstrating the commercial utility of these Lignosulfonates has practical significance. The two isolated biorefinery Lignosulfonates (LSs), Na-LS and Ca-LS, both had a molecular weight of approximately 9000 Da. Fundamental lignin properties such as chemical structure, functional groups were analyzed. The two LSs showed slightly better to equal performance in modifying CWS rheology than a commercial dispersant naphthalene sulfonate formaldehyde condensate (FDN), despite they were less sulfonated than FDN. The practical importance of this study is that the pilot-scale pretreatments that produced the two LSs also produced excellent bioethanol yields at high titer without detoxification and washing. This suggests SPORL pretreatment is a promising technology for economic bioconversion of under-utilized woody biomass.
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adsorption and desorption behaviors of lignosulfonate during the self assembly of multilayers
Bioresources, 2010Co-Authors: Yonghong Deng, Xin Ping Ouyang, Yong Qian, Yuan Wu, Dongjie YangAbstract:Self-assembled multilayers were fabricated from lignosulfonate (LS) and poly(diallyldimethylammonium chloride) (PDAC), and the adsorption and desorption behaviors of LS on the LS/PDAC multilayers under different pH conditions were intensively investigated. Results showed that the adsorption and desorption behaviors were controlled by electrostatic attraction, hydrophobic interaction, and changes in the microstructure, which depended on solution pH. Lignosulfonates exist as colloids in solutions at low pH because of a hydrophobic interactions, and the LS colloids adsorbed on the PDAC layer because of electrostatic attraction. LS colloids started to disassociate at pH 3.5, resulting in an abrupt rise of the adsorption rate, a sharp decrease of the adsorbed amount, and a steep reduction in the surface roughness. Desorption behaviors of LS multilayers were related to the pH values of both LS dipping solution for self-assembly and the immersing solution for post-preparation treatment. Desorption of LS could be induced by a weakening of electrostatic attraction or hydrophobic interaction. A significant desorption occurred only when LS colloids dissociated in the multilayers. LS colloids were harder to dissociate in the multilayers than in the solutions because of electrostatic attraction between LS and PDAC.
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properties of sodium lignosulfonate as dispersant of coal water slurry
Energy Conversion and Management, 2007Co-Authors: Dongjie Yang, Mingsong ZhouAbstract:In order to use Lignosulfonates (a by-product of pulp and paper processes) as an effective dispersant of coal water slurry five purified sodium lignosulfonate (SL) samples with different molecular weights were prepared by fractionation using ultrafiltration and dialysis. The effect of SL on the apparent viscosity of coal water slurry (CWS) was investigated. The adsorption behavior of the SL on the coal water interface has much greater effect on the viscosity of coal water slurry. The higher adsorption amount and compact adsorption film of SL on the coal surface help reduce the viscosity of CWS, and the zeta potential is also an important factor, which is influenced by the sulfonic and carboxyl group contents of the lignosulfonate molecule. Furthermore, the SL with its molecular weight ranging from 10,000 to 30,000 has both a higher adsorbed amount and zeta potential on the coal surface and the best effect on reducing the viscosity of the coal water slurry.