- Beta Zeolite as a Catalyst for the Preparation of Alkyl Glucoside Surfactants: The Role of Crystal Size and Hydrophobicity
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Zeolite H-beta is an active and selective catalyst for the acetalization of the glucose to form alkyl glucoside nonionic surfactants. The characteristics of size and polarity of reactants, intermediates, and products determine the strong influence of the textural properties of the catalyst (crystal size and adsorption properties) on activity, selectivity, and deactivation. For two series of zeolites with different concentrations of Si-O-Si connectivity defects an optimum in activity is found for intermediate Si/Al ratios, this optimum being reached at lower Si/Al ratios in the series with the lower defect concentration, i.e., in the more hydrophobic series. Thus, the optimum catalyst of the hydrophobic series is more active than that of the hydrophilic series, and it also shows a better resistance to deactivation.
- Camblor,Corma,Iborra,Miquel,Primo,Valencia
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- Mesoporous materials as catalysts for the production of chemicals: Synthesis of alkyl glucosides on MCM-41
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The synthesis of alkylglucosides from glucose and n-butanol has been carried out successfully on AL-MCM-41 mesoporous materials. The influence of the chemical composition (Si/Al) and pore dimensionson activity and selectivity has been studied. It has been found that a higher concentration of acid sitesdoes not guarantee a better catalytic performance, and the adsorption-desorption properties of the material play a determinant role in this reaction where the two reactants and the product have very different polarities. On the other hand, in the range of pore sizes studied here, the larger the diameter of the pore at the same level of Al contents, the more activeis the final catalyst. The catalyst loses activity during the process due to the presence of strongly adsorbed molecules. Soxhlet extraction by methanol followed by water does not recover all the initial activity but produces a loss of crystal unity. However, the catalyst could be fully regenerated by calcination in air at 773 K.
- Climent,Corma,Iborra,Miquel,Primo,Rey
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- Bio-based Surfactants
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Bio-based surfactants have great opportunity for use in a variety of applications such as laundry detergents, industrial cleaners, adjuvants, and oil and gas. Surfactants in these applications can be nonionic, anionic, cationic, or amphoteric. Utilizing high oleic soybean oil as a platform chemical, a variety of surfactants and properties can be produced. While early work focused solely on surfactant use in laundry cleaning and fracking, recent work has expanded functional groups and application evaluations in hard surface cleaning. The current invention expands on Battelle's high oleic soybean oil (HOSO) surfactant technology. Use of HOSO overcomes the limitations of regular soybean oil and significantly reduces or eliminates undesirable byproducts in most chemistries. However, with use of select reagents, a few candidates were achievable with regular epoxidized soybean oil (ESO). The HOSO surfactant platform offers several key advantages including: a highly water miscible (not typical of C18 surfactants) and water stable surfactant; ability to adjust and vary hydrophilic-lipophilic (HLB) values for stain removal performance; and increased biodegradability without toxic or persistent by-products.
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- Acid-Assisted Ball Milling of Cellulose as an Efficient Pretreatment Process for the Production of Butyl Glycosides
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Ball milling of cellulose in the presence of a catalytic amount of H2SO4 was found to be a promising pre-treatment process to produce butyl glycosides in high yields. Conversely to the case of water, n-butanol has only a slight effect on the recrystallization of ball-milled cellulose. As a result, thorough depolymerization of cellulose prior the glycosylation step is no longer required, which is a pivotal aspect with respect to energy consumption. This process was successfully transposed to wheat straw from which butyl glycosides and xylosides were produced in good yields. Butyl glycosides and xylosides are important chemicals as they can be used as hydrotropes but also as intermediates in the production of valuable amphiphilic alkyl glycosides.
- Boissou, Florent,Sayoud, Nassim,De Oliveira Vigier, Karine,Barakat, Abdellatif,Marinkovic, Sinisa,Estrine, Boris,Jér?me, Fran?ois
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p. 3263 - 3269
(2015/10/19)
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- Transformation of cellulose into biodegradable alkyl glycosides by following two different chemical routes
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The transformation of cellulose into long-chain alkyl glycoside surfactants has been carried out following two different routes: (1) Direct transformation of cellulose to butyl-, hexyl-, octyl-, decyl- and dodecyl-α,β- glycosides in an ionic liquid media and Amberlyst-15Dry as catalysts, with mass yield of up to 82%; and (2) two steps reaction with transformation of cellulose into methyl glucosides, with a procedure described by Zhang et al., followed by transacetalation with 1-octanol and 1-decanol in the presence of Amberlyst-15Dry. A kinetic study for the direct transformation of cellulose using 1-octanol has shown that depolymerisation of cellulose continues during the Fischer glycosidation. Increasing the chain length of the alcohol decreases the global reaction rate owing to an increase in the lipophilicity of the alcohol that decreases its contact with the carbohydrates. Finally, several acid catalysts were tested and the best results were obtained with Amberlyst-15Dry.
- Villandier, Nicolas,Corma, Avelino
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experimental part
p. 508 - 513
(2012/03/08)
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- One pot catalytic conversion of cellulose into biodegradable surfactants
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Cellulose has been directly converted into environmentally friendly alkyl glycoside surfactants in a one pot transformation. By working in ionic liquid media with Amberlyst 15Dry (A15) as catalyst and coupling the rate of cellulose hydrolysis and the rate of glycosidation of the monosaccharides formed with C4 to C8 alcohols, it was possible to obtain 82% mass yield of octyl-α,β-glucoside plus octyl-α,β-xyloside.
- Villandier, Nicolas,Corma, Avelino
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supporting information; scheme or table
p. 4408 - 4410
(2010/09/15)
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- Substrate specificity in hydrolysis and transglucosylation by family 1 β-glucosidases from cassava and Thai rosewood
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Thai rosewood (Dalbergia cochinchinensis Pierre) dalcochinase and cassava (Manihot esculenta Crantz) linamarase are glycoside hydrolase family 1 β-glucosidases with 47% amino acid sequence identity. Each enzyme can hydrolyze its natural substrate, dalcochinin-8′-O-β-d-glucoside and linamarin, respectively, but not the natural substrate of the other enzyme. Linamarase can transfer glucose to primary, secondary and tertiary alcohols with high efficiency, while dalcochinase can transglucosylate primary and secondary alcohols at moderate levels. In this study, eight amino acid residues in the aglycone binding pocket of dalcochinase were individually replaced with the corresponding residues of linamarase, in order to identify residues that may account for their catalytic differences. The residues I185 and V255 of dalcochinase appeared important for its substrate specificity, with their respective mutations resulting in 24- and 12-fold reductions in k cat/Km for the hydrolysis of dalcochinin-8′-O- β-d-glucoside. Transglucosylation activity was improved when I185, N189 and V255 of dalcochinase were replaced with A201, F205 and F271 of linamarase, respectively, suggesting these residues support transglucosylation in linamarase. Among these three mutants, only the N189F mutant showed significant increases in the rate constants for the reactivation of trapped glucosyl-enzyme intermediates by all alcohols. Together, our results suggest that both hydrophobicity and geometry are important determinants for substrate specificity in hydrolysis and transglucosylation by these family 1 β-glucosidases.
- Kongsaeree, Prachumporn T.,Ratananikom, Khakhanang,Choengpanya, Khuanjarat,Tongtubtim, Nusra,Sujiwattanarat, Penporn,Porncharoennop, Chompoonuth,Onpium, Amornrat,Svasti, Jisnuson
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experimental part
p. 257 - 265
(2011/02/22)
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- Direct conversion of xylan into alkyl pentosides
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Xylan has been used as a raw material in the synthesis of butyl, octyl and decyl glycosides. Mixtures of d-xylose-, l-arabinose- and d-glucose-based surfactants were obtained under smooth conditions with high yields in a one-pot process. The surface activities of octyl and decyl glycosides thus obtained have been studied and compared with that of pure alkyl d-xylosides. The results have confirmed that the new synthetic approach described in this paper is a potentially economical and efficient method for the preparation of environmentally friendly surfactants.
- Bouxin, Florent,Marinkovic, Sinisa,Bras, Jean Le,Estrine, Boris
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scheme or table
p. 2469 - 2473
(2011/01/04)
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- Montmorillonite K-10 as a reusable catalyst for fischer type of glycosylation under microwave irradiation
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Montmorillonite K-10-catalyzed Fischer type glycosylation was studied for various monosacharides with different alcohols under microwave irradiation. The method was found to be efficient, economic, simple, and time saving and the catalyst montmorillonite K-10 was reused three times without loss of catalytic activity and anomeric selectivity. With glycerol, the method gave products glycosylated at primary alcohols only.
- Bordoloi, Manobjyoti
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p. 300 - 308
(2008/12/21)
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- Synthesis of n-alkyl glucosides by amyloglucosidase
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Amyloglucosidase from Rhizopus mold (3.2.1.3) has been employed for the synthesis of n-alkyl glucosides from alcohols of carbon chain lengths Cl to C18 by both shake flask and reflux methods. Glucoside yields obtained from the reflux method (5-44%) are better than those from the shake flask method (3-28%). While the shake flask method favoured glucosylation of medium chain length alcohols, the reflux method at pH 5.0, favoured glucosylation of all the chain lengths. n-Octyl-D-glucoside, n-octyl-maltoside and n-octyl-sucroside are also synthesized and optimum conditions for the synthesis of n-octyl-D-glucoside at both shake flask and reflux methods have been worked out.
- Vijayakumar, Giriyapura R.,George, Charles,Divakar, Soundar
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p. 314 - 319
(2008/02/09)
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- Alkyl polysaccharide derivatives and compositions
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This invention relates to novel alkylpolysaccharide dertivatives including their salts and compositions comprising said alkyl polysaccharides. The alkyl polysaccharide derivatives are of the formula (I): R1 --(OG)n (X)m, where R1 is hydrogen or a hydrophobic moiety; G is a saccahride residue; and X is a succinic anhydride residue; and n and m are independently chosen from an average value which is between 1 and 200.
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- Gemini surfactants from alkyl glucosides
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1,5-Bis-[6-O-(n-butyl α-D-glucopyranosid)] glutarate 7 was synthesized starting from D-glucose by a simple procedure. The anomeric mixture of alkylglucosides was separated by flash chromatography of their peracetates. Detritylation in neutral conditions is described. This is the first example of a non ionic gemini surfactant where alkyl glucosides are linked through a spacer at C-6.
- Castro, Mariano J. L.,Kovensky, Jose,Fernandez Cirelli, Alicia
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p. 3995 - 3998
(2007/10/03)
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- Use of alkylglycoside sulfosuccinates for the production of cosmetic preparations and cleaning agents
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The invention relates to alkylglycoside sulfosuccinates of the general formula (1) defined herein, useful in cosmetic preparations.
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