2 edition of dioxane extraction of lignin from wood found in the catalog.
dioxane extraction of lignin from wood
Gilbert Merle Witcraft
Written in English
|Statement||by Gilbert Merle Witcraft.|
|The Physical Object|
|Pagination||23 leaves, bound :|
|Number of Pages||23|
Lignin has been shown to be a recalcitrance factor in many biomass conversion studies. To better understand the effects of lignin on cellulose conversion, different lignin fractions were extracted from the same dilute acid pretreated corn stover by three sequential isolation methods, namely ethanol extraction, dioxane extraction, and enzyme purification. A common method for chemically isolating residual lignin involves extraction via acidic dioxane. Prior to using this lignin isolation technique, kraft pulps are typically extracted with acetone to remove extractives. The extracted pulp is then refluxed under an inert atmosphere (i.e., nitrogen or argon) with M HCl in dioxane:water.
The lignins were either commercially available (Indulin AT kraft lignin from softwood) or isolated from whole plant material by acid-dioxane extraction. Phenols were isolated from the crude liquid pyrolyzate by extraction with alkali. A further study has been made of the isolation, by acidolysis, of lignin from aspen wood meal (Populustremuloides Michx.) using a dioxane–water () solvent medium containing hydrogen chloride and a low extraction temperature of 87 ± 2° for a short extraction time of s so isolated included those: (a) under different initial acid concentrations of , , , , , 0.
remaining in the wood residue. This activation of lignin improves its removal in a subsequent delignification process (El Hage et al. ; Lora and Wayman ; Reguant et al. ). More than 90% of the original lignin in aspen wood meal was removed by a dioxane:water extraction following a hot water treatment at °C for 4 minutes. In this study, lignins were extracted from three different plant species including poplar (populus nigra), cypress (Cupressus sempervirens), and bagasse (Gramineae Saccharum officinarum L.) by dioxane method and ionic liquid method and their molecular weight distributions (GPC) and their structural features (¹³C NMR) were compared to conclude which of lignins (DL or IL) is more unchanged and.
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In our previous study (Zhang et al. b), a three-step sequential extraction of lignin with 96% dioxane, 50% dioxane, and 80% dioxane containing 1% NaOH was developed for fractional isolation of lignin from wood. About 37% of the original lignin was released from eucalyptus, whereas only % could be isolated with traditional MWL method.
The DPPH radical probing exercises of organo-solvent lignin extraction and regular Kraft lignin were separated by minor modification technique as described by.
Quickly, a lignin test solution in ml of dioxane-water (9/1, v/v) was added to ml of a DPPH solution (25 mg/l in ethanol) as the free radical foundation and kept for 30 min at Cited by: 1. Zhang et al. () studied the extraction of lignin fractions derived from ball-milled sugarcane bagasse by alkaline dioxane extraction processes.
Three steps of extractions, successively, were done using 96% dioxane, 50% dioxane, and 80% dioxane containing 1% NaOH at boiling temperature.
First step extraction with 96% dioxaneCited by: This lignin was extracted with dioxane-water () from spruce wood for 6 weeks and called milled wood lignin. p-coumaryl, coniferyl, and sinapyl alcohols were found to be precursors to lignin and called monolignols. They are hydroxycinnamic alcohols containing an aromatic ring and a side-chain of three carbons designated as α, β, and by: wood lignin is purified dioxane extraction of lignin from wood book the aqueous p-dioxane extract offinely milled wood, which has been first extracted with organic solvents to remove extraneous components.
Although it has not been rigorously proved that MWL is representative ofprotolignin, it is considered to be appropriate for most chemical and biological studies.
Milled wood. In the present study, lignin was extracted from debarked bamboo waste of paper industry by soxhlet extraction method with 1,4–Dioxane as main solvent (along with small quantities of catalyst and water). 10 g of biomass results in g of lignin through soxhlet process.
A three-step sequential extraction−precipitation method was used to isolate lignin from Eucalyptus tereticornis. The ball-milled eucalyptus was extracted with 96% dioxane, 50% dioxane, and 80% dioxane containing 1% NaOH at boiling temperature, consecutively resulting in solubilization of lignin and hemicelluloses.
By precipitating such solutions into 70% aqueous ethanol, the hemicelluloses. Three-step extraction of lignin fractions from ball-milled sugarcane bagasse (SCB) was studied with 96% dioxane, 50% dioxane, and 80% dioxane containing 1% NaOH at boiling temperature followed by purification to remove hemicelluloses.
The total yields of hemicelluloses and lignin were % and % based on dried SCB, respectively. " Wood meal is ground in a ball mill either dry or in the presence of non-swelling solvents (ex. toluene), the cell structure of the wood is destroyed and a portion of lignin (usually less than 50%) can be obtained from the suspension by extraction with a dioxane-water mixture.
" MWL preparation always contain some carbohydrate materials. You may use also dioxane with the only water addition when extracting so caled "native lignin" from milled wood. You may either use acetic acid with addition of 10 to 20 % of H2O. A review of extraction and isolation methods for lignin separation from bagasse is presented.
• Lignin fraction of sugarcane bagasse has a range of 17–32% of biomass. • Lignin fraction has an average value is about 23% of biomass. • Lignin fraction of sugarcane bagasse value has a major content in among of non-wood biomass.
Mixture of dioxane (Diox) and H 2 O has long been used for lignin extraction due to its excellent lignin solubility (Schuerch,Quesada-Medina et al., ). However, hash treatment conditions (more than °C) are necessary to achieve high lignin removal rate even with mineral acid (e.g., H 2 SO 4) catalysis (Miles-Barrett et al., ).
JJ1 ABSTRACT OF THE THESIS OF GILBERT LR1E WITCRAFT for the M.S. iii Chemical Engineering Date Thesis presented J Title The Dioxane Extraction of Lignin From Wood Abstract Approved In order to determine the effect of acid and water concentra- tions on the rate of extraction of lignin, the desired quantities of wood and extracting liquor, made from the necessary amounts of.
Lignin is frequently isolated by the classical Bjӧrkman method and called milled wood lignin (MWL) if wood is the starting material.
The lignin is obtained by milling the extracted sample in a planetary ball mill, followed by extraction with dioxane; after evaporation, the lignin is dissolved in acetic acid, precipitated into water, dried and. Isolation and Structural Characterization of the Milled Wood Lignin, Dioxane Lignin, and Cellulolytic Lignin Preparations from Brewer’s Spent Grain.
Journal of Agricultural and Food Chemistry63 (2), DOI: /jfc. The structure of the lignin from brewer’s spent grain (BSG) has been studied in detail. Three different lignin preparations, the so-called “milled-wood” lignin (MWL), dioxane lignin (DL), and cellulolytic lignin (CEL), were isolated from BSG and then thoroughly characterized by pyrolysis GC/MS, 2D-NMR, and derivatization followed by reductive cleavage (DFRC).
For extraction of Kraft lignin, the black liquor after chemical cooking of woods was precipitated at various pH values by using sulfuric acid. For Klason lignin, the wood was extracted directly in accordance with TAPPI T Strandard.
separated from the wood in the form of "milled wood lignin" (MWL), "dioxane lignin", or "enzymically. In this study, lignins were extracted from three different plant species including poplar (populus nigra), cypress (Cupressus sempervirens), and bagasse (Gramineae Saccharum officinarum L.) by dioxane method and ionic liquid method and their molecular weight distributions (GPC) and their structural features (¹³C NMR) were compared to conclude which of lignins (DL or IL) is more.
Lignin extracted with acidic dioxane was investigated as a possible standard for quantitatively determining lignin content in plant samples using the spectrophotometric method employing acetyl bromide.
Acidic dioxane lignins were analyzed for carbohydrate, total protein, nitrobenzene oxidation products, and UV spectral characteristics. Total carbohydrate content of. American Chemical acetylated acid adhesives ALCELL lignin alkaline American Chemical Society aqueous aromatic association blends bonding calibration chain Chem Chemistry chloride chromatography column components concentration crosslinked curve degradation dioxane elution epoxide ethanol ether extraction formaldehyde fraction functionality.
Through the use of wood-processing side streams for lignin isolation and preparation of nontoxic and biodegradable LNPs, costs of future products can additionally be reduced as well as environmental impacts of otherwise for energy generation used residual biomass from wood processing.
33−35 The availability of considerable amounts of residual.The wood-NaOH solution was added dropwise into acidic 1,4-dioxane/water (, v/v) solution under magnetic stirring and continued agitation for 24 h for sufficient lignin extraction. A certain amount of HCl was added in advance to ensure that the final pH of the mixture was 2.Lignin isolation via preceding extraction of pulp is usually applied on wood as a starting material.
The procedure preceded by cell wall extraction and combined with lignin complexation with thioglicolic acid is used for plant tissues containing various kinds of cells or low lignin .