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- Author:
- Helen L. Ngo, et al. ; Yunzhi Chen; Girma Biresaw; Steven C. Cermak; Terry A. Isbell; Li Chen; Amber L. Durham; Show all 7 Authors
- Source:
- The journal of the American Oil Chemists' Society 2020 v.97 no.3 pp. 231-241
- ISSN:
- 0003-021X
- Subject:
- Physaria; biodegradability; biolubricants; carboxylic ester hydrolases; catalysts; coconuts; cold; cosmetics; estolides; fatty acids; petroleum; pour point; temperature; vegetables; viscosity
- Abstract:
- ... Estolides are bio‐based oils synthesized from fatty acids or from the reaction of fatty acids with vegetable oils. Estolides have many advantages as lubricant base oils, including excellent biodegradability and cold flow properties. Promising applications for estolides include bio‐lubricant base oils and in cosmetics. In this review, the synthesis of estolides from fatty acids using four different ...
- DOI:
- 10.1002/aocs.12323
- https://doi.org/10.1002/aocs.12323
- Author:
- Helen L. Ngo
- Source:
- The journal of the American Oil Chemists' Society 2015 v.92 no.4 pp. 613-619
- ISSN:
- 0003-021X
- Subject:
- neutralization; biolubricants; isomerization; fatty acids; polyolefin; catalytic activity; zeolites; oils; chemists; composite polymers; cosmetics; additives
- Abstract:
- ... Isostearic acids (IA) are highly utilized for industrial purposes especially in the area of biolubricants, such as cosmetics and slip additives for polyolefin and related copolymer films. This study was designed to develop a zeolitic catalysis process for efficient IA production through isomerization of fatty acids. The process utilized zeolite protonated Ferrierite with a small amount of base add ...
- Handle:
- 10113/60656
- DOI:
- 10.1007/s11746-015-2608-5
- https://doi.org/10.1007/s11746-015-2608-5
- Author:
- Helen L. Ngo
- Source:
- Lipid Technology 2014 v.26 no.11-12 pp. 246-248
- ISSN:
- 0956-666X
- Subject:
- biodegradability; branched chain fatty acids; catalysts; cosmetics; synthesis; technology; temperature; zeolites
- Abstract:
- ... “Isostearic acids” (IA) are branched-chain fatty acids that are nontoxic and biodegradable in nature. They are predominantly used in cosmetics because of their superior moisturizing properties as they are odorless, provide smooth spreading and a non-tacky feeling when applied onto skin. They can also be used in applications which require excellent thermo-stability and low flow temperature properti ...
- Handle:
- 10113/60658
- DOI:
- 10.1002/lite.201400066
- https://doi.org/10.1002/lite.201400066
- Author:
- Helen L. Ngo
- Source:
- European journal of lipid science and technology 2014 v.116 no.5 pp. 645-652
- ISSN:
- 1438-7697
- Subject:
- acid treatment; analytical methods; catalysts; heat treatment; hydrogenation; isomerization; oleic acid; zeolites
- Abstract:
- ... Ferrierite zeolite solid is an excellent catalyst for the skeletal isomerization of unsaturated linear‐chain fatty acids (i.e., oleic acid) to unsaturated branched‐chain fatty acids (i.e., iso‐oleic acid) follow by hydrogenation to give saturated branched‐chain fatty acids (i.e., isostearic acid). In order for the isomerization process to be cost effective, the spent zeolite catalyst must be capab ...
- DOI:
- 10.1002/ejlt.201300315
- https://doi.org/10.1002/ejlt.201300315
- Author:
- Helen L. Ngo, et al. ; Robert O. Dunn; Michael J. Haas; Show all 3 Authors
- Source:
- journal of the American Oil Chemists' Society 2015 v.92 no.6 pp. 853-869
- ISSN:
- 0003-021X
- Subject:
- additives; biodiesel; branched chain fatty acids; canola; canola oil; climate; cold; diesel fuel; ethanol; fatty acid methyl esters; fluid mechanics; isomers; methanol; mixing; pour point; soybean oil; soybeans; temperature; transesterification; viscosity
- Abstract:
- ... Biodiesel is an alternative diesel fuel derived mainly from the transesterification of plant oils with methanol or ethanol. This fuel is generally made from commodity oils such as canola, palm or soybean and has a number of properties that make it compatible in compression-ignition engines. Despite its many advantages, biodiesel has poor cold flow properties that may impact its deployment during c ...
- Handle:
- 10113/62250
- DOI:
- 10.1007/s11746-015-2643-2
- https://doi.org/10.1007/s11746-015-2643-2
6. Techno-Economic Analysis of an Improved Process for Producing Saturated Branched-Chain Fatty Acids
- Author:
- Helen L. Ngo, et al. ; Winnie C. Yee; Andrew J. McAloon; Michael J. Haas; Show all 4 Authors
- Source:
- Journal of agricultural science 2014 v.6 no.10 pp. 158-168
- ISSN:
- 1916-9760
- Subject:
- biodiesel; branched chain fatty acids; catalysts; cost effectiveness; esters; freezing; isomerization; models; oleic acid; production costs; stearic acid; temperature; zeolites
- Abstract:
- ... Methyl-branched fatty acids produced by isomerization of oleic acid (‘isostearic’ acids (IA)) are industrially useful products with excellent thermostabilities and lubricities and reduced freezing points relative to stearic acid. They have potential utility as biodiesel or a biodiesel additive imparting improved low temperature fluidity. We present a techno-economic model for industrial scale prod ...
- Handle:
- 10113/60661
- DOI:
- 10.5539/jas.v6n10p158
- https://doi.org/10.5539/jas.v6n10p158
- Author:
- Helen L. Ngo, et al. ; Heather Vanselous; Gary D. Strahan; Michael Haas; Show all 4 Authors
- Source:
- journal of the American Oil Chemists' Society 2013 v.90 no.4 pp. 563-570
- ISSN:
- 0003-021X
- Subject:
- acylglycerols; catalytic activity; diphenylamine; esterification; fatty acids; free fatty acids; salts; transesterification
- Abstract:
- ... Diphenylamine sulfate (DPAS) and diphenylamine hydrochloride (DPACl) salts were found to be highly active catalysts for esterification and substantial transesterification of inexpensive greases to fatty acid methyl esters (FAME). In the presence of catalytic amounts of DPAS or DPACl and excess methanol, the free fatty acids as well as the acylglycerols in waste greases were converted to FAME at 12 ...
- DOI:
- 10.1007/s11746-012-2200-1
- https://doi.org/10.1007/s11746-012-2200-1
- Author:
- Helen L. Ngo, et al. ; Richard D. Ashby; Alberto Nunez; Show all 3 Authors
- Source:
- Journal of the American Oil Chemists' Society 2012 v.89 no.10 pp. 1885-1893
- ISSN:
- 0003-021X
- Subject:
- Pseudomonas; bacteria; biodegradation; branched chain fatty acids; carbon; feedstocks; gas chromatography; isomers; microbial growth; spectroscopy
- Abstract:
- ... Three strains of Pseudomonas bacteria were screened for their capabilities of degrading chemically synthesized saturated branched-chain fatty acids (sbc-FAs). Mixtures of sbc-FAs with the methyl-branch located at various locales along the fatty acid were used as a carbon feedstock in shake-flask culture. Utilization (and hence degradability) of the sbc-FAs was monitored based on positive bacterial ...
- Handle:
- 10113/60282
- DOI:
- 10.1007/s11746-012-2092-0
- https://doi.org/10.1007/s11746-012-2092-0
- Author:
- Helen L. Ngo, et al. ; Robert O. Dunn; Eunha Hoh; Show all 3 Authors
- Source:
- European journal of lipid science and technology 2013 v.115 no.6 pp. 676-683
- ISSN:
- 1438-7697
- Subject:
- esterification; fatty acid esters; industry; isomerization; isomers; mass spectrometry; methanol; oleic acid; temperature
- Abstract:
- ... Iso‐oleic acid is a mixture of C₁₈‐unsaturated branched‐chain fatty acid isomers with a methyl group on various positions of the alkyl chain, which is the product of the skeletal isomerization reaction of oleic acid and is the intermediate used to make isostearic acid (C₁₈‐saturated branched‐chain fatty acid isomers). Methyl iso‐oleate, a mixture of C₁₈‐unsaturated branched‐chain fatty acid methyl ...
- DOI:
- 10.1002/ejlt.201200323
- https://doi.org/10.1002/ejlt.201200323
- Author:
- Helen L. Ngo, et al. ; Pamela S. Fox; Alberto Nuñez; Robert A. Moreau; Michael J. Haas; Show all 5 Authors
- Source:
- European journal of lipid science and technology 2014 v.116 no.3 pp. 344-351
- ISSN:
- 1438-7697
- Subject:
- analytical methods; animal fats and oils; biodegradability; isomers; oleic acid; phenol; renewable resources; vegetable oil; zeolites
- Abstract:
- ... There is significant research interest in developing new industrial materials from vegetable oils and animal fats. Such biobased materials can be more environmentally friendly because they tend to have good biodegradability and are derived from renewable resources. This paper describes a catalytic approach for the addition of phenol to the olefinic site of oleic acid using the H‐ferrierite zeolite ...
- DOI:
- 10.1002/ejlt.201300227
- https://doi.org/10.1002/ejlt.201300227
- Author:
- Helen L. Ngo, et al. ; Eunha Hoh; Thomas A. Foglia; Show all 3 Authors
- Source:
- European journal of lipid science and technology 2012 v.114 no.2 pp. 213-221
- ISSN:
- 1438-7697
- Subject:
- additives; biodegradable products; catalysts; cosmetics; fatty acid composition; isomers; lubricants; monounsaturated fatty acids; oils; renewable resources; saturated fatty acids; sustainable technology; zeolites
- Abstract:
- ... The development of viable technologies for producing green products from renewable fats and oils is highly desirable since such materials can serve as replacements for nonârenewable and poorly biodegradable petroleumâbased products. Mixtures of saturated branchedâchain fatty acid isomers (sbcâFAs), commonly referred to as isostearic acid, are important intermediates for the production of b ...
- DOI:
- 10.1002/ejlt.201000471
- https://doi.org/10.1002/ejlt.201000471
- Author:
- Helen L. Ngo, et al. ; Richard D. Ashby; Daniel K. Y. Solaiman; Gary Strahan; Show all 4 Authors
- Source:
- Applied microbiology and biotechnology 2009 v.85 no.2 pp. 359-370
- ISSN:
- 0175-7598
- Subject:
- polyhydroxyalkanoates; chemical composition; biosynthesis; Pseudomonas resinovorans; microbial physiology; stearic acid; metabolites; isomers; decanoic acid
- Abstract:
- ... Pseudomonas resinovorans, a known medium-chain-length (mcl-) poly(hydroxyalkanoate) (PHA) producer, was grown on 13-methyltetradecanoic acid (13-MTDA) and a mixture of isostearic acid (IA) isomers to produce methyl-branched mcl-PHA polymers. Shake-flask experiments revealed polymer productivities (the percent of the cell mass that is polymer) of 31 ± 1% (n = 3) and 23 ± 3% (n = 3) when grown in 13 ...
- Handle:
- 10113/42572
- DOI:
- 10.1007/s00253-009-2134-1
- PubMed:
- 19644690
- https://doi.org/10.1007/s00253-009-2134-1
- Author:
- Helen L. Ngo, et al. ; Alberto Nuñez; Wenbin Lin; Thomas A. Foglia; Show all 4 Authors
- Source:
- European journal of lipid science and technology 2007 v.109 no.3 pp. 214-224
- ISSN:
- 1438-7697
- Subject:
- isomerization; thermogravimetry; X-ray diffraction; stearic acid; catalysts; isomers; zeolites; scanning electron microscopy; Fourier transform infrared spectroscopy; mass spectrometry; gas chromatography; oleic acid; biobased products; branched chain fatty acids
- Abstract:
- ... 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 ...
- Handle:
- 10113/14432
- DOI:
- 10.1002/ejlt.200600246
- https://doi.org/10.1002/ejlt.200600246
- Author:
- Helen L. Ngo, et al. ; Chuan-De Wu; Wenbin Lin; Show all 3 Authors
- Source:
- Chemical communications 2004 v. no.14 pp. 1588-1589
- ISSN:
- 1364-548X
- Subject:
- chemical reactions; coordination polymers; luminescence; perchlorates; silver; silver nitrate
- Abstract:
- ... The reactions of 2,2′-dimethoxy-1,1′-binaphthyl-3,3′-bis(4-vinylpyridine) (L) with AgNO₃ or AgClO₄ at 70 °C gave rise to two novel luminescent homochiral lamellar coordination polymers, AgL₂X (X = NO₃⁻ for 1 or ClO₄⁻ for 2), which are built from linking helical chains by Ag(i) atoms as hinges. ...
- DOI:
- 10.1039/b403609c
- https://doi.org/10.1039/b403609c
- Author:
- Helen L. Ngo, et al. ; Aiguo Hu; Wenbin Lin; Show all 3 Authors
- Source:
- Chemical communications 2003 v. no.15 pp. 1912-1913
- ISSN:
- 1364-548X
- Subject:
- ambient temperature; catalytic activity; enantioselectivity; esters; hydrogenation; ionic liquids; methanol
- Abstract:
- ... Polar phosphonic acid-derived Ru-BINAP systems were used to catalyze asymmetric hydrogenation of β-keto esters in room temperature ionic liquids (RTILs) with complete conversions and ee values higher than those obtained from homogeneous reactions in MeOH (up to 99.3%), and were recycled by simple extraction and used for four times without the loss of activity and enantioselectivity. ...
- DOI:
- 10.1039/b302637j
- https://doi.org/10.1039/b302637j
- Author:
- Helen L. Ngo, et al. ; Yong Cui; Wenbin Lin; Show all 3 Authors
- Source:
- Chemical communications 2003 v. no.12 pp. 1388-1389
- ISSN:
- 1364-548X
- Subject:
- chemical compounds; chemical reactions
- Abstract:
- ... A homochiral triple helix was self-assembled from an axially chiral bipyridine and a linear metal-connecting point, which further assembles into a 2D network via infinite π⋯π stacking interactions and acts as a host for the inclusion of guest molecules. ...
- DOI:
- 10.1039/b212781d
- https://doi.org/10.1039/b212781d
- Author:
- Helen L. Ngo, et al. ; Yong Cui; Peter S. White; Wenbin Lin; Show all 4 Authors
- Source:
- Chemical communications 2002 v. no.16 pp. 1666-1667
- ISSN:
- 1364-548X
- Subject:
- chemical reactions; dicarboxylic acids; enantiomers; ligands; topology
- Abstract:
- ... Homochiral 3D metal–organic open frameworks based on enantiopure atropisomeric dicarboxylic acid bridging ligands and dilanthanide secondary building units exhibit an unprecedented 4⁹6⁶ topology, and possess ethoxy-protected BINOL functionalities that are pointing toward the open channels. ...
- DOI:
- 10.1039/b204249e
- https://doi.org/10.1039/b204249e
- Author:
- Helen L. Ngo, et al. ; Yong Cui; Peter S. White; Wenbin Lin; Show all 4 Authors
- Source:
- Chemical communications 2003 v. no.8 pp. 994-995
- ISSN:
- 1364-548X
- Subject:
- chemical reactions; coordination polymers; hydrogen bonding
- Abstract:
- ... Homochiral 3D open frameworks have been assembled from 1- and 2-D coordination structures via hydrogen bonding and are stable towards the removal of included guest molecules. ...
- DOI:
- 10.1039/b211916a
- https://doi.org/10.1039/b211916a
- Author:
- Helen L. Ngo, et al. ; Nicholas A. ZafiropoulosContributed equally to this work.; Thomas A. Foglia; Edward T. Samulski; Wenbin Lin; Show all 5 Authors
- Source:
- Chemical communications 2007 v. no.35 pp. 3670-3672
- ISSN:
- 1364-548X
- Subject:
- biodiesel; catalysts; catalytic activity; esterification; esters; feedstocks; free fatty acids; transesterification
- Abstract:
- ... Recyclable and reusable heterogeneous diarylammonium catalysts are highly effective in catalyzing the esterification of the free fatty acid (FFA) present in greases to methyl esters to reduce the FFA content from 12–40 wt% to 0.5–1 wt%; the resulting ester–glyceride mixture (pretreated grease) could then be readily converted to methyl esters by base-catalyzed transesterification. ...
- DOI:
- 10.1039/b704189f
- https://doi.org/10.1039/b704189f