Generation of water-soluble organic acids from kerogen during hydrous pyrolysis: implications for porosity development

1987 ◽  
Vol 51 (362) ◽  
pp. 495-503 ◽  
Author(s):  
T. I. Eglinton ◽  
C. D. Curtis ◽  
S. J. Rowland

AbstractConcentrations of organic acids ranging up to several thousand parts per million have previously been found in oil-field waters. These acids are of interest because of their potential to enhance porosity by the dissolution of carbonates and aluminosilicates. They are believed to be generated from organic geopolymers (kerogen) in the late-diagenetic-early-catagenetic stage of thermal maturation.During the course of artificial maturation experiments in which kerogens of varying type were heated in the presence of water (so-called ‘hydrous pyrolysis’) and different minerals, the distribution and abundance of low molecular weight water-soluble acids were determined by gas chromatography and gas chromatography-mass spectrometry. Preliminary results suggest that significant quantities of mono- and di-carboxylic acids are produced during hydrous pyrolysis. The amounts and types of acid appear to vary as a function of kerogen type, maturity and mineralogy. Implications of these findings regarding the development of secondary porosity are discussed.

2002 ◽  
Vol 29 (7) ◽  
pp. 899 ◽  
Author(s):  
Sjaan D. Bidwell ◽  
Ian E. Woodrow ◽  
George N. Batianoff ◽  
Jens Sommer-Knudsen

Throughout the world, over 400 species of plants are known to accumulate large quantities of metals in their shoots (`hyperaccumulators'), but of these, relatively few accumulate manganese (Mn). We have identified for the first time an Australian native hyperaccumulator of Mn, Austromyrtus bidwillii (Benth.) Burrett (Myrtaceae). Concentrations of Mn up to 19 200 µg g-1 were measured in dried leaves of this rainforest tree, and young bark was found to contain up to 26 500 µg g-1 Mn. Approximately 40% of the Mn in the leaves is readily extracted with water, suggesting that some of the Mn is associated with water-soluble compounds such as organic acids. Organic acids present in appreciable amounts in leaf extracts of A. bidwillii were identified and quantified by HPLC and gas chromatography-mass spectrometry. The following organic acids (in order of concentration) were present: succinic > malic ≥ malonic > oxalic >> citric acid. The concentration of total organic acids was on average 123 000 µg g-1 dry tissue, which amounted to approximately three times the molar equivalent of Mn and two times the molar equivalent of total cations (Mn, Mg and Ca), demonstrating that organic anions were in excess. The Mn remaining after water extraction ((61 ± 3.9%) could be extracted with 0.2M HCl, suggesting that a significant portion of the Mn is associated with the cell wall (perhaps replacing Ca) or is present as other insoluble compounds.


2013 ◽  
Vol 46 (6) ◽  
pp. 654-659 ◽  
Author(s):  
E. V. Shamrikova ◽  
I. V. Gruzdev ◽  
V. V. Punegov ◽  
F. M. Khabibullina ◽  
O. S. Kubik

1997 ◽  
Vol 43 (2) ◽  
pp. 149-156 ◽  
Author(s):  
Jin W. Lee ◽  
Walter G. Yeomans ◽  
Alfred L. Allen ◽  
David L. Kaplan ◽  
Frank Deng ◽  
...  

Three different exopolymers were purified from cultures of Agrobacterium sp. strain ATCC 31749 grown in a mineral salts medium containing 2% glucose at 30 °C for 5 days under aerobic culture conditions. These exopolymers were curdlan (extracellular, homo-β-(1-3)-glucan, water insoluble at neutral pH), a water-soluble noncurdlan-type exopolymer A (WSNCE-A), and a water-soluble noncurdlan-type exopolymer B (WSNCE-B). Curdlan, WSNCE-A, and WSNCE-B composed by weight 61, 27, and 12%, respectively, of the exopolymer produced from glucose. Compositions of all polymers were confirmed by gas chromatography (GC) and gas chromatography – mass spectrometry (GC–MS). The WSNCE-A is composed of glucose and galactose with lower contents of rhamnose. The WSNCE-B consists of glucose and mannose. To biosynthesize modified biopolymers, glucose-related sugars including 3-O-methyl-D-glucose, 2-amino-2-deoxy-D-glucose, and 2-acetamido-2-deoxy-D-glucose (N-acetylglucosamine) were fed separately as the sole carbon source. Using 3-O-methyl-D-glucose, 8 – 12 mol% of the curdlan repeats were 3-O-methyl-D-glucose based on GC and 1H-nuclear magnetic resonance spectrometry. N-Acetylglucosamine was incorporated into WSNCE-A at 10 mol% based on the GC–MS but was not found in curdlan or WSNCE-B.Key words: Agrobacterium sp., curdlan, exopolymer, 3-O-methyl-D-glucose, 2-acetamido-2-deoxy-D-glucose.


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