Characterization of products from clay catalyzed polymerization of tall oil fatty acids

Dery

et al. 2004

J Surfact & Detergents

Fatty acids are the primary natural starting materials for the production of surfactant and detergent molecules. Derived from vegetable (oil) and animal (fat) triglyceride sources, the fatty acids are linear aliphatic carboxylic acids. Industrial interest in branched-chain fatty acids is driven by the needs for products with enhanced performance benefits including higher solubility, ease of handling, better hard water tolerance, and improved oxidative stability. Therefore, catalytic processes have been developed for the conversion of linear fatty acids to branched ones. High yields of branched acids are obtained from unsaturated fatty acids over acidic zeolites, particularly those with large pores. Fatty esters also are readily isomerized to branched ones by means of the same catalyst and process. It is postulated that the isomerization of fatty acids proceeds through three-and four-membered ring carbocation intermediates formed inside the largepore zeolites. This is supported by evidence of methyl and ethyl branching in the primary and final products. The total number of carbon atoms in the fatty acid molecule is unchanged. Surfactants derived from branched fatty acids show favorable physical properties, including a lower viscosity and improved handling, even as intended performance characteristics are maintained. Abbreviations: BFA, branched fatty acid; HIO, hydrogenated isomerized oleic acid; HO, hydrogenated oleic acid; IV, iodine value.

Section: Background In the Synthesis Of Branched-chain Fatty Acidsmentioning

confidence: 99%

New process for the production of branched‐chain fatty acids

Dery

et al. 2004

J Surfact & Detergents

“…The branched-chain acids have the same number of carbon atoms as the parent acids in the feed. From tall oil fatty acids, methyl branching predominates with a branch methyl group to acid ratio of about 1.3 [13].…”

Section: Introductionmentioning

confidence: 99%

Skeletal isomerization of unsaturated fatty acids: the role of mesopores in HBeta zeolites

2007

Catal Lett

Fatty acids are an important class of feedstock for the production of many chemicals, such as surfactants, lubricants, biodiesel, etc. Fatty acids derived from vegetable oils and animal fats typically have linear aliphatic chain, and are therefore called linear fatty acids. Products based on branched fatty acids offer many attractive properties over those based on linear ones, e.g. low melting points and low viscosity. Catalytic skeletal isomerization of linear fatty acids to branched ones is particularly important for industrial production of branched fatty acids. This paper for the first time reveals the key properties of the most active zeolite catalysts for this reaction. Among many solid acid catalysts studied, acidic Beta zeolites were found to stand out in their performance for the reaction. In this work, several acidic Beta zeolites (HBeta) from commercial sources were evaluated for their performance in fatty acid skeletal isomerization. The activities of these zeolites under identical test conditions were found to vary in a wide range, even with similar silica to alumina molar ratios (SAR). A combination of characterization techniques was used to systematically investigate the most critical property of the zeolites responsible for the observed superior activity. All the HBeta zeolites in this study have high crystallinity. Pore size distribution of the zeolites was identified to be the most important factor that unambiguously correlates the catalyst activity to the amount of mesopores in the HBeta zeolites.

Euro J Lipid Sci & Tech

“…In 1994, Neuss et al [3] reported that, with a montmorillonite clay catalyst in combination with an active carbon, sunflower oil FA/ esters could be converted to bc-isomers in yields between 30 and 40%. Although bc-acids can be synthesized using clay catalysts [4], there are several drawbacks to using them. First, conversion of the linear UFA is modest at best and, secondly, the clay catalysts give primarily oligomeric byproducts (mainly dimers and trimers) and thus have a rather low selectivity to bc-FA.…”

Section: Introductionmentioning

confidence: 99%

“…Interestingly, the four types of zeolites referenced above all have uni-dimensional channels. The rigid aluminosilicate networks are made up of tetrahedral SiO 4 and AlO 4 molecules and possess negative charges in the framework wherever the tetravalent Si is replaced by the trivalent Al. In order to balance the charges, zeolites typically contain counter ions such as Na 1 , K 1 , Ca 21 , NH 4 1 and H 1 inside the cavities and channels [12].…”

Section: Introductionmentioning

confidence: 99%

Zeolite‐catalyzed isomerization of oleic acid to branched‐chain isomers

Ngo

Núñez

Lin

et al. 2007

Zeolite-catalyzed isomerization of oleic acid to branched-chain isomers*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.