Waste Lignin Research Articles

ПРИМЕНЕНИЕ СЕРОСОДЕРЖАЩЕГО СОРБЕНТА НА ОСНОВЕ ЛИГНИНА ДЛЯ ИЗВЛЕЧЕНИЯ РТУТИ ИЗ ВОДНЫХ РАСТВОРОВ

The article presents data on the use of sulfur-containing sorbent obtained on the basis of tonnage of waste lignin, as well as on the basis of organochlorine wastes from epichlorohydrin production, for the extraction of mercury and mercury salts from aqueous solutions. For obtaining of sorbents lignin previously had been subjected to chlorination by the action of chlorine water (chlorine content of 3.5 - 5.7 per cent). The obtained powders of sorbents differ in sulphur content and content of residual chlorine in the finished product. The results of investigations of sorption properties of the sorbent, as well as its kinetic and thermodynamic characteristics. The sorption activity of this sorbent, while the extraction of mercuric ions from solutions at room temperature has a good performance. Kinetic studies are consistent with the comprehensive coordination mechanism of absorption of mercury ions. These studies will help to solve some global environmental problems, including wastewater treatment from heavy metals, recycling organochloride wastes from epichlorohydrin production and also utilization of large-tonnage waste of pulp and paper industry and hydrolytic lignin.

Lignin conversion to hydrogen-containing gas under the action of microwave radiation

The paper describes the carbon dioxide reforming of lignin in the presence of Ni-, Fe, and Ni/Fe-containing active components formed directly on the surface under microwave irradiation. The deposition of 0.1 wt % iron acetylacetonate on the lignin surface results in a sharp increase in the microwave absorption capacity at a 0.5 kW power and induces lignin conversion to hydrogen-containing gas with a degree of hydrogen recovery reaching 90 %. The maximum lignin conversion (65%) is attained in 10 min under microwave irradiation. It was shown for the first time that deposition of metals (Fe and Ni) on lignin can provide for targeted change of the selectivity of reforming to synthesis gas and the process can thus be classified as a plasma catalytic one. Using the obtained results, it is possible to minimize the amount of catalyst and to propose an efficient route for hydrogen and synthesis gas production from lignin waste.

Biosorbents for Removing Hazardous Metals and Metalloids.

Biosorbents for remediating aquatic environmental media polluted with hazardous heavy metals and metalloids such as Pb(II), Cr(VI), Sb(III and V), and As(III and V) were prepared from lignin waste, orange and apple juice residues, seaweed and persimmon and grape wastes using simple and cheap methods. A lignophenol gel such as lignocatechol gel was prepared by immobilizing the catechol functional groups onto lignin from sawdust, while lignosulfonate gel was prepared directly from waste liquor generated during pulp production. These gels effectively removed Pb(II). Orange and apple juice residues, which are rich in pectic acid, were easily converted using alkali (e.g., calcium hydroxide) into biosorbents that effectively removed Pb(II). These materials also effectively removed Sb(III and V) and As(III and V) when these were preloaded with multi-valent metal ions such as Zr(IV) and Fe(III). Similar biosorbents were prepared from seaweed waste, which is rich in alginic acid. Other biosorbents, which effectively removed Cr(VI), were prepared by simply treating persimmon and grape wastes with concentrated sulfuric acid.

Novel multidimensional carbons from structural transformations of waste lignin: A low temperature pyrolysis investigation

Low temperature pyrolysis investigations were carried out on waste lignin, a coproduct of bioethanol production from sugarcane bagasse, in the temperature range 200–800°C for 15 to 60min under argon atmosphere. In-depth characterization of resulting chars was carried out using a range of analytical techniques including XRD, HRSEM, EDS, NMR, FTIR, Raman and BET analysis. In addition to good agreement with the published literature, we report the formation of range of multidimensional carbons from waste lignin in the form of nanofibers, micro-ribbons, complex 3D structures and their blends. XRD data showed the evolution of crystalline as well as amorphous structures as a function of temperature. Reaction pathways for structure evolution and associated phase transformations were also identified. The preparation of these novel carbon structural forms from an abundant, waste bioresource could help realize the untapped potential of waste lignin, the exploration of their properties and future applications.

Utilization of Waste Lignin and Hydrolysate From Chromium Tanned Waste in Blends of Hot-Melt Extruded PVA-Starch

The demand for biodegradable plastic material is increasing worldwide. However, the cost remains high in comparison with common forms of plastic. Requirements comprise low cost, good UV-stability and mechanical properties, as well as solubility and water uptake lead to the preparation of multi-component polymer blends based on polyvinyl alcohol and starch in combination with waste products that are hard to utilize—waste lignin and hydrolysate extracted from chromium tanned waste. Surprisingly the addition of such waste products into PVA gives rise to blends with better biodegradability than commercial PVA in an aquatic aerobic environment with non-adapted activated sludge. These blends also exhibited greater solubility in the water and UV stability than commercial PVA. Tests on the processing properties of the blends (melt flow index, tensile strength and elongation at break of the films) as well as their mechanical properties showed that materials based on these blends might be applied in agriculture (for example as the systems for controlled-release pesticide or fertilizer) and, somewhat, in the packaging sector.

Lignin-based catalysts for Chinese fir furfurylation to improve dimensional stability and mechanical properties

In order to valorize lignin from spent liquor of pulping mills, a novel catalyzing system for wood furfurylation which composed of lignin-derived acids (LDAs, i.e. lignosulfonic acid and sulfomethylated lignin acid) and buffer sodium borate was developed, and was applied to Chinese fir furfurylation for improved dimensional stability and mechanical properties. LDAs were prepared by protonating of sulfomethylated lignin and lignosulfonate through cation exchange resin. The catalyzing system was optimized by the storage duration of FA formulas with respective catalyzing system at room temperature and the curing time at elevated temperature. Then, three formulas were selected out to treat Chinese fir and their performance was evaluated by weight percentage gain, dimensional stability, and compressive strength. The results showed that LDAs, especially sulfomethylated lignin acid, penetrated into cell walls and catalyzed furfurylation reaction quite well. The best performance achieved in this study by Formula III was with weight percentage gain of 66.4%, equilibrium moisture content 12.9%, anti-swelling efficiency 61.9% and 70.6% for the conditions of high humidity and water-soaking, respectively; its parallel-to-grain compressive strength was improved by 45.4%. It hints lignin-derived acids combined with borate would be a promising catalyst system for wood furfurylation since it valorizes both the waste lignin and low-valued wood.

One‐Pot Process for Hydrodeoxygenation of Lignin to Alkanes Using Ru‐Based Bimetallic and Bifunctional Catalysts Supported on Zeolite Y

The synthesis of high-efficiency and low-cost catalysts for hydrodeoxygenation (HDO) of waste lignin to advanced biofuels is crucial for enhancing current biorefinery processes. Inexpensive transition metals, including Fe, Ni, Cu, and Zn, were severally co-loaded with Ru on HY zeolite to form bimetallic and bifunctional catalysts. These catalysts were subsequently tested for HDO conversion of softwood lignin and several lignin model compounds. Results indicated that the inexpensive earth-abundant metals could modulate the hydrogenolysis activity of Ru and decrease the yield of low-molecular-weight gaseous products. Among these catalysts, Ru-Cu/HY showed the best HDO performance, affording the highest selectivity to hydrocarbon products. The improved catalytic performance of Ru-Cu/HY was probably a result of the following three factors: (1) high total and strong acid sites, (2) good dispersion of metal species and limited segregation, and (3) high adsorption capacity for polar fractions, including hydroxyl groups and ether bonds. Moreover, all bifunctional catalysts proved to be superior over the combination catalysts of Ru/Al2 O3 and HY zeolite.

Pyrolysis of industrial waste lignin: Analysis of product yields and character

ABSTRACTSlow pyrolysis of industrial waste lignin has been carried out in a lab-scale tube furnace reactor at 300–700°C, and the effect of temperature on yields and character of pyrolytic products (bio-char, bio-oil and gas) was investigated. The results showed that pyrolysis temperature played an important role on the conversion of waste lignin into high value-added products. Bio-char was the dominant product of waste lignin, whose quality improved with increasing temperature, while the best combustion reactivity was focus at 500°C. The optimum condition for bio-oil formation was at 600°C, where contained a mass of phenols. Gas yield significantly increased effected by temperature, especially CH4.

Cellulose on Miscibility and Thermal Studies of Acetate and Modified Industrial Waste Lignin Blends

Cellulose on Miscibility and Thermal Studies of Acetate and Modified Industrial Waste Lignin Blends

Economic Evaluation of Lignocellulosic Biofuel Manufacturing Considering Integrated Lignin Waste Conversion to Hydrocarbon Fuels

Although lignin accounts for 20%-25% of the total weight of dry lignocellulosic feedstock, it is largely wasted in the lignocellulosic ethanol industry due to the challenging nature of decomposing lignin polymers. In fact, through a series of chemical processes, lignin can be converted into hydrocarbon biofuels with a very low oxygen content; thus making them suitable to be combined with conventional fossil fuels for transportation fuel applications. In this paper, we present a framework to guide biofuel manufacturers seeking to extend traditional lignocellulosic biofuel manufacturing processes to process lignin waste and convert it to hydrocarbon biofuels. Additionally, we conducted an economic viability assessment on such integrated production processes by comparing to the baseline case based on the NREL 2011 bio-ethanol process design. The findings show that using lignin waste, the integrated manufacturing processes can produce 16 million gallons of hydrocarbon fuel in addition to the 67 million gallons of ethanol compared to the baseline case. In addition, the economic evaluation shows that the production cost per unit energy produced increases by only 3.97%, which indicates the integrated production scheme has great potential to be economically viable.

Preserving and Maintaining Culinary-Medicinal Royal Sun Mushroom, Agaricus brasiliensis (Agaricomycetes), in Sterile Distilled Water.

Strains of Agaricus brasiliensis require special procedures for conservation. Thus, the objective of this research was to establish conservation and maintenance procedures A. brasiliensis strain PSWC838 from the University of Pennsylvania (ABWC838) and an A. brasiliensis strain from the Fujian Agriculture and Forestry University (ABC). The medium in which mycelia grew the quickest for both strains was selected using a multifactorial design with 2 strains, 4 culture media, and incubation for 5 different times; the growth rate (mm/day) was the response variable. Analysis of variance showed that the potato dextrose agar (PDA) medium and potato extract did not display a significantly different growth rate, and PDA was selected for safety reasons. We also evaluated the viability of the strains grown on PDA and 0.2% activated carbon after 3 months of storage in sterile distilled water. A factorial design was applied with 2 factors, the strain and incubation for 10 different times. The Tukey post hoc test indicated that ABC showed quicker and more homogeneous growth than ABWC838. Finally, the results showed that pieces of mycelium of ABC and ABWC838 strains inoculated on the PDA medium with 0.2% activated carbon and preserved in sterile distilled water at 18 ± 1°C showed 100% viability after 3 months of storage. Moreover, the results of semiquantitative biochemical tests confirmed that the production of laccases and amylases was preserved in these strains after storage in sterile water, enhancing their ability to degrade substrates containing lignin and starchy waste.

Quality carbon fibers from fractionated lignin

A strategy was developed to produce quality carbon fibers from industrial waste lignin. The strategy employs an enzyme-mediator system to efficiently fractionate lignin into soluble and insoluble fractions, where the latter serves as a superior carbon fiber precursor. Mechanistic studies revealed that higher MW, less hydroxy groups, and more β-O-4 linkages improve the spinnability, crystallization, and mechanical performance of carbon fibers.

Tricin‐lignins: occurrence and quantitation of tricin in relation to phylogeny

Tricin [5,7-dihydroxy-2-(4-hydroxy-3,5-dimethoxyphenyl)-4H-chromen-4-one], a flavone, was recently established as an authentic monomer in grass lignification that likely functions as a nucleation site. It is linked onto lignin as an aryl alkyl ether by radical coupling with monolignols or their acylated analogs. However, the level of tricin that incorporates into lignin remains unclear. Herein, three lignin characterization methods: acidolysis; thioacidolysis; and derivatization followed by reductive cleavage; were applied to quantitatively assess the amount of lignin-integrated tricin. Their efficiencies at cleaving the tricin-(4'-O-β)-ether bonds and the degradation of tricin under the corresponding reaction conditions were evaluated. A hexadeuterated tricin analog was synthesized as an internal standard for accurate quantitation purposes. Thioacidolysis proved to be the most efficient method, liberating more than 91% of the tricin with little degradation. A survey of different seed-plant species for the occurrence and content of tricin showed that it is widely distributed in the lignin from species in the family Poaceae (order Poales). Tricin occurs at low levels in some commelinid monocotyledon families outside the Poaceae, such as the Arecaceae (the palms, order Arecales) and Bromeliaceae (Poales), and the non-commelinid monocotyledon family Orchidaceae (Orchidales). One eudicotyledon was found to have tricin (Medicago sativa, Fabaceae). The content of lignin-integrated tricin is much higher than the extractable tricin level in all cases. Lignins, including waste lignin streams from biomass processing, could therefore provide a large and alternative source of this valuable flavone, reducing the costs, and encouraging studies into its application beyond its current roles.

Formaldehyde salvages lignin

During biomass processing, tens of millions of metric tons of lignin waste are produced each year. This wasteful sludge could be avoided by simply adding formaldehyde in the early stages of the pro...

Utilization of waste lignin to prepare controlled-slow release urea

The present work reports an economically attractive improvement in the area of producing particulate slow release nitrogen fertilizer using lignin as a waste effluent of pulp and paper manufacturing process. An improved coating of modified lignin was applied on the surfaces of the individual urea particles. The Kraft and Sulfite black liquors obtained from two different paper pulping units and were used as sources of sulfate and sulfite lignin, respectively. Chemical modification of extracted lignin was performed through acetylation reaction by acetic acid/sodium metabisulfite to increase its hydrophobicity character. In a separate experiment, a thin layer of synthesized acetylated lignin was coated on granular urea by fluidized-bed technique. The nitrogen release of synthesized fertilizer in the water and soil was examined by the Kjeldahl method. The analysis of FTIR spectra indicated the changes in the functional groups of acetylated lignin. Petrographic photography and scanning electron microscopy (SEM) analyses demonstrated a uniform and homogeneous covering of the urea surface. The 7 day nitrogen release rate of urea coated by acetylated lignin in soil was obtained 36.3 and 45.3 % for Kraft and Sulfite lignin, respectively, whereas this value was 59 % for sulfur coated urea. Using industrial wastewater as source of lignin gives satisfactory results for industrial applications and yields a quality green fertilizer product with reduced operation difficulties while considerably preserving the environment.

Insight into the solvent, temperature and time effects on the hydrogenolysis of hydrolyzed lignin

The aim of this study is to explore the reaction mediums and conditions for producing high yield of valuable monomers from concentrated sulfuric acid hydrolyzed lignin. The solvent, temperature and time effects on the hydrogenolysis of hydrolyzed lignin were investigated under the catalysis of Pd/C and CrCl3. Supercritical methanol exhibits the best depolymerization performance, because of its unique diffusion, dissolution and acid-base properties. Afterwards, the influence of reaction temperature and time on depolymerization, repolymerization and coking during hydrogenolysis was examined in methanol. The high temperature is found to favor the depolymerization, with the β-O-4 linkages cleaved significantly. However, the repolymerization is promoted simultaneously, and a high amount of β-β groups form. These reactions are in constant competition with each other and the repolymerization is preferred at excessive high temperature, producing bulk char residues, that is coking. This study will provide a beneficial reference for the maximization of lignin waste valorization.

Challenging/interesting lignin times

Anyone who is working in the fuels industry knows that we are living in challenging times. On a personal note, I recall that ~5 years ago, some of my children's friends headed out into the petroleum industry to start their careers and several have now returned because of the retrenching work force. Despite these challenging times, the cellulosic ethanol industry continues to develop commercial operations, but with today's cost structure, biofuels production facilities have certainly slowed their pace of development and roll-out. Furthermore, the biological technology platform for biorefining plant polysaccharides to biofuels has been reported to have an intrinsic advantage, if it can convert its waste lignin stream to value-added components.[1]

Effect of water–carbon dioxide ratio on the selectivity of phenolic compounds produced from alkali lignin in sub- and supercritical fluid mixtures

Lignin is considered as the most abundant renewable carbon source after cellulose and non-commercialized waste product with constantly growing annual production exceeding 50milliontonsperyear. This article is focused on a newly developed selective synthesis of high-value phenolic products from lignin in presence of supercritical carbon dioxide (scCO2) known as sustainable, non-flammable, naturally abundant, and catalytically active solvent. Depending on the synthesis conditions, such as temperature (250, 300, and 350°C) and water-to-scCO2 ratio (1:5, 1:2, 1:1, and 2:1), high yield of the specific phenolic compounds such as phenol, guaiacols, and vanillin has been achieved. The GCMS analysis reveals the trend of the increased total phenolic yield with temperature and strong dependence of the selectivity on the water-to-scCO2 ratio. The maximum selectivity toward formation of the specific phenolic products, such as guaiacol and vanillin was observed at the highest H2O:scCO2=1:5 ratio. At 350°C the relative yield of guaiacol was ∼39% whereas at 250°C vanillin was a dominant phenolic monomer with a relative yield of ∼33%. Moreover, at the intermediate temperature of 300°C both guaiacol and vanillin were produced with relative yields of ∼28% and ∼13%, respectively. The highest amounts of scCO2 resulted in the highest total relative phenolic yields of ∼79%, ∼71%, and ∼73% at 250, 300, and 350°C, respectively. Demonstrated for the first time, the effect of water-to-scCO2 ratio in the process of alkali lignin liquefaction will have significant impact on selective synthesis of phenolic compounds, their use in synthesis of “green” polymers with desirable properties, and sustainable utilization of both carbon dioxide and lignin waste.

Isolation of bacterial strains able to metabolize lignin and lignin-related compounds.

In this study, we identified five strains isolated from soil and sediments able to degrade kraft lignin, aromatic dyes and lignin derivatives. Using 16S rRNA gene sequencing, the isolates were identified as Serratia sp. JHT01, Serratia liquefacien PT01, Pseudomonas chlororaphis PT02, Stenotrophomonas maltophilia PT03 and Mesorhizobium sp. PT04. All the isolates showed significant growth on lignin with no water-extractable compounds. Synthetic aromatic dyes were used to assess the presence of oxidative enzymes. All the isolates were able to use the thiazine dye Methylene blue and the anthraquinone dye Remazol Brilliant Blue R as the sole carbon source. Guaiacol, veratryl alcohol and biphenyl were also mineralized by all the strains isolated. These results suggest they could be used for the treatment of aromatic pollutants and for the degradation of the lignocellulosic biomass. The valorization of waste lignin and lignocellulosic biomass by biocatalysis opens up new possibilities for the production of value-added substituted aromatics, biofuel and for the treatment of aromatic pollutants. Bacteria with ligninolytic potential could be a source of novel enzymes for controlled lignin depolymerization. In this work, five soil bacteria were isolated and studied. Every isolate showed significant growth on lignin and was able to degrade several lignin monomers and ligninolytic indicator dyes. They could thus be a source of novel ligninolytic enzymes as well as candidates for a bacterial consortium for the delignification of lignocellulosic biomass.

Two-dimensional mass defect matrix plots for mapping genealogical links in mixtures of lignin depolymerisation products.

Lignin is the second most abundant natural biopolymer, and lignin wastes are therefore potentially significant sources for renewable chemicals such as fuel compounds, as alternatives to fossil fuels. Waste valorisation of lignin is currently limited to a few applications such as in the pulp industry, however, because of the lack of effective extraction and characterisation methods for the chemically highly complex mixtures after decomposition. Here, we have implemented high resolution mass spectrometry and developed two-dimensional mass defect matrix plots as a data visualisation tool, similar to the Kendrick mass defect plots implemented in fields such as petroleomics. These 2D matrix plots greatly simplified the highly convoluted lignin mass spectral data acquired from Fourier transform ion cyclotron resonance (FTICR)–mass spectrometry, and the derived metrics provided confident peak assignments and strongly improved structural mapping of lignin decomposition product series from the various linkages within the lignin polymer after electrochemical decomposition.Graphical 2D mass defect matrix plot for a lignin sample after decompositionElectronic supplementary materialThe online version of this article (doi:10.1007/s00216-016-9598-5) contains supplementary material, which is available to authorized users.