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简单介绍了甲酸的用途;介绍了国外甲酸生产技术进展,甲酸甲酯法生产甲酸四种主要工艺的优缺点.国内甲酸生产技术发展和肥城阿斯德化工有限公司在甲酸甲酯法生产甲酸项目中的技术刨新情况;以及国内外甲酸产品的市场需求情况和未来几年甲酸发展前景。 相似文献
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介绍了甲酸酯化法、甲醇催化脱氢法、合成气直接合成法、甲醇羰基化法等甲酸甲酯的7种合成方法及制甲酰胺、二甲基甲酰胺、甲酸、醋酸等方面的7种用途 相似文献
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活性炭改性对用于甲酸分解的Pd/活性炭催化剂的影响 总被引:1,自引:0,他引:1
采用磁力搅拌法和水浴振荡法制备应用于甲酸分解的Pd/活性炭(AC)催化剂,研究了活性炭载体改性和制备方法对催化剂分解甲酸性能的影响。采用恒温水浴振荡装置,在80℃水浴中进行甲酸催化分解反应,以甲酸的催化分解率评价催化剂催化活性。结果表明,以经过不同的酸、碱、盐溶液改性后的活性炭为载体采用不同方法制备的Pd/AC催化剂对甲酸的催化分解效果不同,以Na2CO3改性的活性炭为载体采用磁力搅拌法制备的催化剂活性最好,甲酸水溶液的分解率达85%以上,含甲酸的工业废水的分解率达70%。 相似文献
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We report on a capillary GC-MS method for the quantitative analysis of hydroxy and epoxy FA. Catalytic hydrogenation of lipid
extracts produces stable saturated lipids. Saponification followed by methylation with boron trifluoride in the presence of
methanol converts FA to methyl esters and epoxy groups to methoxy-hydroxy groups. These compounds are purified from nonoxidized
methyl esters using solid phase extraction. Derivatization of the hydroxy group using tetramethylammonium hydroxide forms
methoxy and vicinal dimethoxy FAME. When subjected to El-MS, fragmentation gives two characteristic ion fragments for each
epoxy and hydroxy positional isomer. Quantitative measurements were achieved using uniformly labeled hydroxy and epoxy 13C FA as internal standards. Epoxy and hydroxy FA were identified in both plasma and adipose tissue of men, and the levels
of hydroxy and epoxy in these tissues were related. The levels of hydroxy isomers were typical of oxidation of linoleic acid,
whereas epoxy isomers were characteristic of oxidation of oleic acid. 相似文献
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Franz Ulberth Robert G. Gabernig Franz Schrammel 《Journal of the American Oil Chemists' Society》1999,76(2):263-266
The concept of theoretical response factors is not directly applicable to methyl esters of short-chain fatty acids (FA), since
their carbon deficiency is larger than expected from theory. Substituting the methyl group by an ethyl, propyl, or butyl group
improved the flame-ionization efficiency of fatty acid esters gradually, up to the point where the empirical response factors
of the butyl esters were identical within experimental error to the theoretical values. Butyl esters of FA have a uniform
flame-ionization detection (FID) response irrespective of the number of carbon atoms contained in the FA. They exhibit a carbon
deficiency of 1.0, i.e. the carbonyl carbon atom does not respond, as expected from theory. Compared to methyl esters, which
have a carbon deficiency of 1.4–1.5 for short-chain FA, use of butyl esters has the advantage that a precalculation of the
FID response enables the analyst to judge whether the analytical system employed works properly and the data produced are
accurate and reliable. Both acid (BF3 or H2SO4)-and alkali (butoxide)-catalyzed butyl ester preparation were equally effective, giving the analyst a choice of methods so
that different analytical needs can be addressed efficiently. Computing response factors and comparing the theoretically expected
values with those obtained experimentally gives the experimenter an indication whether the analytical system employed for
FA profiling (transesterification plus the subsequent gasliquid chromatographic separation and quantitation by FID) works
properly. This setup is particularly useful for an accurate analysis of the FA profile of milk fat. 相似文献
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Melha Kendel Gilles Barnathan Joël Fleurence Vony Rabesaotra Gaëtane Wielgosz-Collin 《Lipids》2013,48(5):535-545
Phospholipids (PL) and glycolipids (GL) FA in the edible Rhodophyta Grateloupia turuturu, from Brittany, France, were investigated over four seasons. The major lipid class was GL in all seasons (around 45 %). More than 80 FA occurred in polar lipids, with chains from C12 to C26, identified as methyl esters and N-acyl pyrrolidides by gas chromatography–mass spectrometry (GC–MS). PUFA occurred at up to 47.1 % (summer) in PL, and up to 43.6 % (summer) in GL. The major PUFA were 20:5n-3 (12.2 % in PL and 29.0 % in GL) and 20:4n-6 (25.6 % in PL and 10.4 % in GL). The unusual 18:3n-7 acid was identified in PL up to 2.2 %. Several minor unsaturated FA were identified in PL and are previously unreported in seaweeds, namely 14-tricosenoic, 15-tetracosenoic, 5,11-octadecadienoic and 5,9-nonadecadienoic. Also unprecedented in seaweeds, ten 2-hydroxy and three 3-hydroxy FA occurred mainly in PL, 13.9 % in spring with the 3-hydroxyhexadecanoic acid as the major one (8.1 % winter). Three n-9 monounsaturated 2-hydroxy FA occurred in PL. The 2-hydroxy-15-tetracosenoic acid was characterized as the dimethyl disulfide adduct of its methyl ester. The 2-hydroxy-16-pentacosenoic and 2-hydroxy-17-hexacosenoic acids were identified by comparison of mass spectra and GC mobilities with those of the 2-hydroxy-15-tetracosenoic acid, and of other homogeneous FA series. These rare n-9 monounsaturated 2-hydroxy FA are unprecedented in seaweeds. 相似文献
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Tomasz Sledzinski Adriana Mika Piotr Stepnowski Monika Proczko-Markuszewska Lukasz Kaska Tomasz Stefaniak Julian Swierczynski 《Lipids》2013,48(8):839-848
Fatty acids containing a cyclopropane ring in their structure (cyclopropane FA) have been found in a wide variety of bacteria, a number of protozoa, and Myriapoda. Little is known about cyclopropane FA in mammal, especially in human tissues. The present study deals with the identification of cyclopropane FA in adipose tissue and serum of humans and rats. Fatty acids extracted from the adipose tissue and serum obtained from obese women during bariatric surgery were methylated and analyzed on GC–MS. We have identified: cyclopropaneoctanoic acid 2-hexyl, cyclopropaneoctanoic acid 2-octyl, cyclopropanenonanoic acid, and 2-[[2-[(2-ethylcyclopropyl)methyl]cyclopropyl]methyl] acid in human adipose tissue. We confirmed the presence of cyclopropaneoctanoic acid 2-hexyl by derivatization of FA extracted from human adipose tissue to picolinyl esters. Cyclopropaneoctanoic acid 2-hexyl was the main cyclopropane FA (approximately 0.4 % of total fatty acids in human adipose tissue, and about 0.2 % of total fatty acids in the serum). In adipose tissue cyclopropaneoctanoic acid 2-hexyl was found mainly in triacylglycerols, whereas in serum in phospholipids and triacylglycerols. The cyclopropaneoctanoic acid 2-hexyl has also been found in serum, and adipose tissue of rats in amounts comparable to humans. The content of cyclopropaneoctanoic acid 2-hexyl decreased in adipose tissue of rats maintained on a restricted diet for 1 month. In conclusion, we demonstrated that cyclopropaneoctanoic acid 2-hexyl is present in human adipose tissue and serum. Adipose tissue cyclopropaneoctanoic acid 2-hexyl is stored mainly in triacylglycerols and the storage of this cyclopropane FA is affected by food restriction. 相似文献
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The oxidation of well-defined FA derivatives has been studied with real-time IR (RTIR) and chemiluminescence (CL) techniques.
Both methyl esters and model oils based on different FA have been studied to reveal the effect of functionality. The FA used
were linoleic and crepenynic acid, the latter with an alkyne functionality. The purpose was to reveal how structural differences
affect the oxidation and how this is monitored with CL and RTIR. Both model oils had longer oxidation induction times than
the corresponding methyl esters, as seen by both IR and CL. Generally, the induction times measured with IR were shorter than
those determined by CL, but the rate of oxidation did not seem to differ much between the model oils and the corresponding
methyl esters. The results also imply that the higher functionality of the model oils gives a greater possibility of intramolecular
addition reactions instead of chain scission during oxidation, making the model oils emit fewer low-M.W. volatiles than the
methyl esters. There is also a difference between methyl crepenynate and methyl linoleate, in that the alkyne functionality
seems to enhance the possibility of chain scission instead of addition reactions. The results presented imply that the CL
signal can be used to monitor the oxidation and the formation of volatile compounds from a FA structure. By combining the
CL measurements with RTIR data, information about the oxidation reactions can be obtained, giving a greater understanding
of what reactions are occurring during oxidation and how they are related to each other. 相似文献
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《The Journal of Supercritical Fluids》2007,39(3):275-288
In this review, the phase behavior of lipids in ternary and higher systems was analyzed to determine the effect of operating parameters and feed composition on solubility behavior and separation efficiency. The ternary systems studied included two triglycerides (TG) (trilaurin (LLL)/tripalmitin (PPP), trimyristin (MMM)/PPP and LLL/MMM), two fatty acids (FA) (oleic acid (OA)/linoleic acid (LA)), two fatty acid methyl esters (FAME) (methyl myristate (MeM)/methyl palmitate (MeP) and methyl oleate (MeO)/methyl linoleate (MeL)), FA/TG (OA/triolein (OOO)) and FAME/FA (MeO/OA) in SCCO2. The quaternary and quinary systems analyzed contained three TG (LLL/MMM/PPP), three glycerides (monoolein (MO)/diolein (DO)/OOO) and four TG (PPP/palmitoyl-dioleoylglycerol (POO)/oleoyl-dipalmitoylglycerol (PPO)/OOO), respectively, in SCCO2. While solubility of the less soluble component increased in ternary systems of solid triglycerides in SCCO2, that of the more soluble component decreased or was not affected. Solubility diminution was observed for both solutes in some liquid mixtures such as fatty acid (oleic acid/linoleic acid) and fatty acid ester (methyl oleate/methyl linoleate) mixtures. Solubility enhancement for one of the mixture components was also observed (for example, for oleic acid in the presence of methyl oleate). Separation efficiency was lower than that predicted by binary data when the solubility of the less soluble solute was enhanced in the mixture, whereas it was improved if the solubility of the more soluble component was enhanced as observed in quaternary glyceride mixtures. 相似文献
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Helen L. Ngo Alberto Nuñez Wenbin Lin Thomas A. Foglia 《European Journal of Lipid Science and Technology》2007,109(3):214-224
Branched‐chain (bc) saturated fatty acids (SFA) have potential as oleochemical intermediates since they have better oxidative stability than linear unsaturated fatty acids (UFA) and have better low‐temperature properties than linear SFA. Previous studies in converting UFA to bc‐FA using clay catalysts have resulted in only modest yields and conversions. Recent reports, however, have suggested that certain zeolites can be effective catalysts for converting UFA to bc‐FA in higher yields and conversions. In this work, we examined the scope and potential of the zeolite‐catalyzed synthesis of bc‐FA starting from readily available monounsaturated linear FA. Our results show that common UFA such as oleic acid can be converted to bc‐isomers using modified Ferrierite zeolite catalysts with high conversions (98%) and high selectivity (85%) and that the zeolite catalysts are reusable for at least three cycles. The positions of branching (methyl) on the FA chain were determined from the GC‐MS spectra of the picolinyl esters of the bc‐FA. 相似文献
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Fatty Acid Composition of Seeds From Wild and Cultivated Ginseng (Panax ginseng Meyer): Occurrence of a High Level of Petroselinic Acid 下载免费PDF全文
Vasily I. Svetashev Olga L. Burundukova Tamara I. Muzarok Yuri N. Zhuravlev 《Journal of the American Oil Chemists' Society》2016,93(9):1319-1323
The lipid content and fatty acid (FA) composition of seeds from the Asian ginseng Panax ginseng growing naturally in taiga forests of the Russian Far East and seeds from cultivated ginseng were studied in this work. The total lipid content of seeds from both wild and cultivated plants was 9–12 % of fresh weight. FA were analyzed as isopropyl esters on a polar capillary column BD‐225, which allows good separation of petroselinic and oleic acids. The structure of FAs was confirmed using GC–MS of fatty acid methyl ester (FAME) and 4,4‐dimethyloxazoline derivatives. In all the seed samples, the major FA was petroselinic acid 18:1(n‐12) which comprised more than 60 %; the contents of oleic and linoleic acids were lower (15–17 and 15–16 %, respectively). Earlier, a higher level (>80 %) of oleic acid had been reported for ginseng seeds. This discrepancy can be explained by an insufficient separation of these acids on standard columns used for GC of FAME. In general, seeds of wild and cultivated ginseng are very similar in lipid content and FA composition. 相似文献
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Previous studies on laboratory rodents, rabbits and humans have demonstrated that fatty acid (FA) mobilization from white
adipose tissue (WAT) is selective and its efficiency is related to FA structure. Selective FA mobilization was also documented
in a carnivore, the farmed raccoon dog (Nyctereutes procyonoides), fasted for 8 weeks. The present study explored whether similar selectivity of FA mobilization was manifested in wild mammals
experiencing seasonal food scarcity and abundance. Fractional mobilization from and incorporation into WAT of a wide spectrum
of FA were studied by gas–liquid chromatography from the subcutaneous WAT of free-ranging raccoon dogs with the same individuals
sampled in consecutive seasons. The wintertime FA mobilization was selective and mostly confirmed the patterns of FA release
in captivity. Mobilization correlated inversely with the FA chain length but increased with unsaturation and when the first
double bond was located closer to the methyl end. 18–20C n-3 polyunsaturated FA (PUFA) and 14–17C monounsaturated FA (MUFA)
were preferentially mobilized while 19–24C saturated FA and MUFA were preserved during wintering. The summertime FA incorporation
correlated inversely with the chain length and increased with unsaturation and in MUFA and PUFA with double bonds closer to
the methyl end. The principles of selective FA mobilization were valid in wild mammals. FA incorporation was also selective
and reversed the wintertime losses of the preferably mobilized FA. 相似文献
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Quévrain E Barnathan G Meziane T Domart-Coulon I Rabesaotra V Bourguet-Kondracki ML 《Lipids》2012,47(4):345-353
The fatty acid composition of the temperate calcareous marine sponge Leuconia johnstoni Carter 1871 (Calcaronea, Calcarea) was characterized for the first time in specimens collected off the Brittany coast of
France over four years from October 2005 to September 2008. Forty-one fatty acids (FA) with chain lengths ranging from C14 to C22 were identified as fatty methyl esters (FAME) and N-acyl pyrrolidide (NAP) derivatives by gas chromatography–mass spectrometry (GC–MS). Twenty-two saturated fatty acids (SFA)
were identified accounting for 52.1–59.0% of the total FA and dimethylacetals (DMA). In addition, among the SFA, we noticed
the presence of numerous methyl-branched iso and anteiso FA, suggesting a large number of associated bacteria within L. johnstoni. Thirteen monounsaturated fatty acids (MUFA, 28.0–36.0% of total FA + DMA) were also identified as well as six polyunsaturated
fatty acids (PUFA, 4.0–8.2%). A noticeable DMA was detected at a high level, particularly in September 2008 (11.8%), indicating
the presence of plasmalogens in this sponge species. This calcareous sponge lacked the non-methylene-interrupted FA (NMI FA)
with a Δ5,9 system typical of siliceous Demosponges and Hexactinellids. The occurrence of the unusual 8,13-octadecadienoic
acid was reported for the first time as a minor PUFA in a calcareous sponge. The major FA, representing 20–25% of this sponge
FA, was identified as the new 2-methyl-13-icosenoic acid from mass spectra of its methyl ester and its corresponding N-acyl pyrrolidide derivatives as well as a dimethyl disulfide adduct. 相似文献