Aldolization of butyraldehyde with formaldehyde over a commercial anion-exchange resin — kinetics and selectivity aspects

Serra-Holm, V.; Salmi, Tapio; Multamäki, J.; Reinik, Janek; Mäki‐Arvela, Päivi; Sjöholm, Rainer; Lindfors, Lars Peter

doi:10.1016/s0926-860x(99)00510-4

Cited by 34 publications

(26 citation statements)

References 13 publications

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“…Solid-base catalysts constitute a class of heterogeneous catalysts that are capable of catalyzing the C-C bond-forming reactions. Different families of solid bases have been found active in this reaction, including alkali-exchanged zeolites [1], ion-exchange resins [2,3], alumina-supported hydroxide [7,8], Mg-Al hydrotalcites [9,10], and alkaline-earth metal oxides [11,12]. In particular, alkaline-earth metal oxides have been regarded as the most potential catalysts for industrial application for their strong basicity and low cost, especially for CaO.…”

Section: Introductionmentioning

confidence: 99%

Efficient aldol condensation by using modified CaO as solid-base catalysts

Tang

Chen

2011

Res Chem Intermed

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A new type of solid-base catalyst for aldol condensation reaction was prepared by modifying commercial CaO with benzyl bromide in a simple way. It was found that modified CaO can effectively catalyze the aldol condensation of acetophenone and benzaldehyde to produce chalcone with a high conversion and good selectivity. The catalyst gave a higher yield (90.5%) of chalcone than commercial CaO. The high catalytic activity and stability of this catalyst was related to the organic modifier with a hydrophilic functional group that improved the diffusion of grease to the catalyst surface and prevented its hydration. The influence of several reaction parameters, such as temperature, catalyst loading and the moisture absorption rate of modified CaO, was investigated. From the results, the basic centers of modified CaO are stable and hardly poisoned by CO 2 unlike commercial CaO. The catalyst was completely recyclable without significant loss in activity up to five reaction cycles. Moreover, this catalyst showed a promising future in providing an environmentally clean process for the industrial sector.

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Section: Introductionmentioning

confidence: 99%

Efficient aldol condensation by using modified CaO as solid-base catalysts

Tang

Chen

2011

Res Chem Intermed

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“…Moreover, it is known that the formation of crotonaldehyde via aldol condensation in starch hydrolyzates does not occur significantly until pH 7.5 and above (Byrne 1989). In addition, the observed diene a,b-unsaturated aldehydes such as 2,4-hexadienal can be accounted for by the aldol condensation of a,b-unsaturated aldehydes (in the case of 2,4-hexadienal this would be crotonaldehyde) and another aldehyde (in this case acetaldehyde) (Serra-Holm et al 2000). If the a,b-unsaturated aldehydes observed at pH 11 were primarily produced by base catalyzed aldol condensation it would help explain their abundance at pH 11 and not at pH3.…”

Section: Final Considerationsmentioning

confidence: 99%

Identification of α-β unsaturated aldehydes as sources of toxicity to activated sludge biomass in polyester manufacturing wastewater

Caffaro-Filho

Wagner

Umbuzeiro

et al. 2010

Water Science and Technology

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Wastewater generated in industrial production processes are often contaminated by hazardous chemicals. Characterization by means of toxicity-directed analysis is useful for identifying which fractions of a waste stream possess the most toxicity. We applied this approach to evaluate toxic components of a polyester manufacturing wastewater. Using the reduction in oxygen uptake rate of activated sludge as an indicator of toxicity, it was determined that increasing the pH from 3 to 11 followed by air stripping significantly reduced the toxicity of the wastewater. Comparative headspace GC/MS analysis of wastewater at different pHs selected a group of Volatile Organic Compounds (VOCs) associated with the observed effect of air stripping at pH 11. Ten of these compounds were identified as alpha,beta unsaturated aldehydes (acrolein (2-propenal) congeners); these compounds are known to be toxic as well as mutagenic. Confirmation that these compounds were a cause of toxicity was achieved by demonstrating that removal of these compounds by air stripping significantly reduced the wastewater mutagenic potency in a Salmonella mutagenicity assay. Formation of these volatile compounds by base catalyzed aldol condensation at pH 11 may account for the effectiveness of air stripping in reducing toxicity. To date there is no record in the literature about the toxicity and presence of acrolein congeners in polyester manufacturing wastewater.

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“…The catalytic activity of commercial AERs was tested by several workers for varieties of reactions, such as oxidation of alcohols [5,6], aldol condensation [7,8], hydration of ethylene oxide [9], nucleophilic substitutions [5,10], alkylations [5,11], oxidation of organic pollutants [12], transesterification reactions for biodiesel production [13] and reduction of nitrotoluenes by aqueous ammonium sulphide [14]. However, synthesis of commercially important products, chloroanilines by the reduction of CNBs with aqueous ammonium sulphide using a solid resin as catalyst was never reported earlier.…”

Section: Introductionmentioning

confidence: 99%

Reduction of Chloronitrobenzenes by Aqueous Ammonium Sulphide: Triphase Catalysis by Anion Exchange Resin

Jeeru

Pradhan

Kundu

2015

Indian Chemical Engineer

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The reduction of chloronitrobenzenes (CNBs) by aqueous ammonium sulphide was carried out using an anion exchange resin (AER) as triphase (Liquid-Liquid-Solid) catalyst. About 66 folds enhancement in rate of reduction of p-chloronitrobenzene was obtained with 20% (W/V) loading of the catalyst. The reactions were observed to be free from mass transfer resistance with apparent activation energies of 9.3, 14.3 and 20.1 kcal/mol for m-chloronitrobenezne (m-CNB), o-chloronitrobenezne (o-CNB) and p-chloronitrobenezne (p-CNB), respectively. The rate of reduction of p-CNB was established to be proportional to the concentration of p-CNB and to the cube of the concentration of sulphide. The triphase catalyst could be reused for four times with insignificant loss in activity.

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Aldolization of butyraldehyde with formaldehyde over a commercial anion-exchange resin — kinetics and selectivity aspects

Cited by 34 publications

References 13 publications

Efficient aldol condensation by using modified CaO as solid-base catalysts

Efficient aldol condensation by using modified CaO as solid-base catalysts

Identification of α-β unsaturated aldehydes as sources of toxicity to activated sludge biomass in polyester manufacturing wastewater

Reduction of Chloronitrobenzenes by Aqueous Ammonium Sulphide: Triphase Catalysis by Anion Exchange Resin

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