Partial Recovery of Aliphatic Carboxylic Acids and Sodium Hydroxide from Hardwood Black Liquor by Electrodialysis

2014 ◽  
Vol 53 (22) ◽  
pp. 9464-9470 ◽  
Author(s):  
Hemanathan Kumar ◽  
Raimo Alén
Keyword(s):  
Sodium Hydroxide ◽  
Carboxylic Acids ◽  
Black Liquor ◽  
Partial Recovery ◽  
Aliphatic Carboxylic Acids

scholarly journals Identification of Some Minor Aliphatic Carboxylic Acids in Birch Kraft Black Liquor.

1986 ◽  
Vol 40b ◽  
pp. 606-608 ◽  
Author(s):  
Klaus Niemelä ◽  
Eero Sjöström ◽  
Bo Angelin ◽  
Kurt Einarsson ◽  
Povl Krogsgaard-Larsen ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Black Liquor ◽  
Kraft Black Liquor ◽  
Aliphatic Carboxylic Acids

Delignification of Bamboo (Bambusa procera acher) Part 2. Characterisation of Kraft Black Liquors from Different Cooking Conditions

Holzforschung ◽  
2003 ◽  
Vol 57 (6) ◽  
pp. 619-626 ◽  
Author(s):  
T. H. M. Vu ◽  
R. Alén ◽  
H. Pakkanen
Keyword(s):  
Chemical Composition ◽  
Carboxylic Acids ◽  
Black Liquor ◽  
Kraft Pulping ◽  
Laboratory Scale ◽  
Black Liquors ◽  
The Individual ◽  
Aliphatic Carboxylic Acids ◽  
Inorganic Constituents ◽  
Cooking Conditions

Summary Bamboo (Bambusa procera acher) was delignified in a laboratory-scale digester by conventional kraft pulping under varying conditions. Pulps with kappa numbers in the range 12.9–56.3 and viscosities in the range 871–1319 ml g−1 were obtained. The chemical composition of the corresponding black liquors was analysed with respect to their main organic and inorganic constituents. The results indicated that the dry solids of the black liquor contained 40–44% lignin, 20–24% aliphatic carboxylic acids, 4–7% polysaccharides and the residual matter (about 30%) consisted mainly of inorganic constituents. Of the monosaccharide moieties detected in the polysaccharides, xylose was predominant, suggesting that xylan was a major hemicellulose constituent in the black liquor. The effect of effective alkali, sulphidity and H-factor of the cook on the formation of the individual constituents in the black liquor is also discussed.

scholarly journals Role of lignin and sodium carbonate on the swelling behavior of black liquor droplets during combustion

Holzforschung ◽  
2018 ◽  
Vol 72 (3) ◽  
pp. 179-185
Author(s):  
Chengcong Chen ◽  
Hannu Pakkanen ◽  
Raimo Alén
Keyword(s):  
Carboxylic Acids ◽  
Sodium Carbonate ◽  
Molar Mass ◽  
Lignin Content ◽  
Black Liquor ◽  
The Other ◽  
Partial Removal ◽  
Aliphatic Carboxylic Acids ◽  
Lower Molar

AbstractA partial removal of lignin from black liquor (BL) by carbonation and lignin precipitation was studied. In lignin-lean BL droplets during combustion in a laboratory furnace at 800°C in stagnant air, the maximum swelling was decreased. This observation was interpreted as showing that the lignin content decrement is due mainly to removal of higher molar mass (HMM) lignin and that the Na2CO3content of the BL is increased. Stepwise precipitation experiments with industrial softwood and hardwood kraft BLs by carbonation (resulting in pH decrement from 13 to 9) indicated that a fraction of HMM lignin (MM >10 kDa) with a higher amount of carbohydrates precipitated more prominently and earlier than the fraction with lower molar mass (LMM) lignin (MM <10 kDa) containing less amounts of carbohydrates. Separate experiments with a 50/50 (by wt) mixture of different lignin fractions (1–5, 5–10 and >10 kDa) and BL-originated aliphatic carboxylic acids were performed and found that the mixture of medium MM fraction (MM 5–10 kDa) swelled more than the other lignin fractions. The addition of Na2CO3to BL also reduced the maximum swelling of a BL droplet.

Generation of Phosphoranyl Radicals via Photoredox Catalysis Enables Voltage–Independent Activation of Strong C–O Bonds

2018 ◽  
Author(s):  
Erin Stache ◽  
Alyssa B. Ertel ◽  
Tomislav Rovis ◽  
Abigail G. Doyle
Keyword(s):  
Carboxylic Acids ◽  
Functional Groups ◽  
Single Step ◽  
Direct Access ◽  
Photoredox Catalysis ◽  
Acyl Radical ◽  
Synthetic Strategy ◽  
Acyl Radicals ◽  
Benzyl Radicals ◽  
Aliphatic Carboxylic Acids

Alcohols and carboxylic acids are ubiquitous functional groups found in organic molecules that could serve as radical precursors, but C–O bonds remain difficult to activate. We report a synthetic strategy for direct access to both alkyl and acyl radicals from these ubiquitous functional groups via photoredox catalysis. This method exploits the unique reactivity of phosphoranyl radicals, generated from a polar/SET crossover between a phosphine radical cation and an oxygen centered nucleophile. We first show the desired reactivity in the reduction of benzylic alcohols to the corresponding benzyl radicals with terminal H-atom trapping to afford the deoxygenated product. Using the same method, we demonstrate access to synthetically versatile acyl radicals which enables the reduction of aromatic and aliphatic carboxylic acids to the corresponding aldehydes with exceptional chemoselectivity. This protocol also transforms carboxylic acids to heterocycles and cyclic ketones via intramolecular acyl radical cyclizations to forge new C–O, C–N and C–C bonds in a single step.

Improved QSAR Analysis of the Toxicity of Aliphatic Carboxylic Acids

2003 ◽  
Vol 73 (11) ◽  
pp. 1792-1798 ◽  
Author(s):  
F. P. Maguna ◽  
M. B. Ninez ◽  
N. B. Okulik ◽  
E. A. Castro
Keyword(s):  
Carboxylic Acids ◽  
Qsar Analysis ◽  
Aliphatic Carboxylic Acids

Radical addition to acrylonitrile via catalytic photochemical decarboxylation of aliphatic carboxylic acids

2013 ◽  
Vol 54 (32) ◽  
pp. 4324-4326 ◽  
Author(s):  
Yasuharu Yoshimi ◽  
Sonoka Washida ◽  
Yoshiki Okita ◽  
Keisuke Nishikawa ◽  
Kousuke Maeda ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Radical Addition ◽  
Aliphatic Carboxylic Acids

Syntheses, structures, and properties of multidimensional lithium coordination polymers based on aliphatic carboxylic acids

2013 ◽  
Vol 42 (8) ◽  
pp. 2765-2772 ◽  
Author(s):  
Pei-Chi Cheng ◽  
Wei-Cheng Lin ◽  
Feng-Shuen Tseng ◽  
Ching-Che Kao ◽  
Ting-Guang Chang ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Coordination Polymers ◽  
Structures And Properties ◽  
Aliphatic Carboxylic Acids
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