Efficient cenosphere supported catalyst for the esterification of n-octanol with acetic acid

Abstract

An efficient heterogeneous acid catalyst was developed using cenospheres, a byproduct of coal-fired thermal power plants by the method of wet impregnation. Catalyst characterization was carried out using various analytical techniques, namely, Fourier transform infrared, X-ray diffraction, field emission gun scanning electron microscopy and Brunauer eEmmetteTeller surface area and surface acidity analysis. The characterization revealed the excellent catalytic activity of the catalyst for the esterification reaction of n-octanol and acetic acid. Various reaction parameters, namely, catalyst loading, a molar ratio of alcohol/ acid and reaction temperature were evaluated and optimized by response surface methodology using the BoxeBehnken model. The response surface methodology model equations corresponding to the conversion of acid and % yield of ester were developed. The model well predicted the optimal reaction conditions, which were validated experimentally with good agreement. The excellent catalytic performance was observed in the esterification reaction with high conversion of acid (95.34%) and high yield of n-octyl acetate (94.81%). Reusability study of the catalyst showed that the catalyst could be used efficiently up to three reaction cycles. This study explores the use of cenospheres to prepare a solid acid catalyst for the industrially important esterification reactions.

Novel Nickel- and Magnesium-Modified Cenospheres as Catalysts for Dry Reforming of Methane at Moderate Temperatures

“…Cenospheres, present in fly ash, are hollow particles of about 10-1000 µm in diameter, with a density lower than 1 g/cm 3 [5]. These could become catalyst supports for certain chemical processes that require high thermal stability [6,7]. Cenospheres are composed of a mixture of aluminosilicates with some amount of K, Ca, Fe, Mg, and a small addition of Ti, Na, P, S, and trace elements [7].…”

“…Because of the high amount of Al 2 O 3 (23%-33%) and the fact that they were formed at temperatures over 1200 • C, cenospheres have high mechanical and thermal strength, and thus have potential applications in many branches of industry [8]. Cenospheres were examined and have exhibited positive results as catalysts, for example, for esterification of n-octanol with acetic acid [6], for deNOx processes [9], as well as in practical uses in the degradation of pollutants or for water cleanup [10]. Additionally, it was concluded that when used as catalysts, they can show high conversion and selectivity for some important organic reactions under solvent-free conditions [11].…”

Recovery of Cenospheres and Fine Fraction from Coal Fly Ash by a Novel Dry Separation Method

“…There are numerous applications of such material that have been recently studied e.g. cement-based composites [4], particulate reinforced metal matrix composites [5], polymer composites [6][7][8][9], a catalytic support [10][11][12][13] or a fluidised bed material [14][15][16][17]. The main reason for the applying of cenospheres in the composites is to reduce their weight and manufacturing cost, as well as to improve their properties e.g.…”

Response Surface Methodology and Artificial Neural Networks for Optimization of Catalytic Esterification of Lactic Acid

“…In the context of environmental sustainability, heterogeneous catalysts such as ion-exchange resins [4], zeolites [5], ionic liquids [6,7], fly ash cenospheres [8], enzymes [9], Brønsted acids [10,11], and Lewis acids [12,13] were investigated. Apart from these reports, studies related to application of waste materials for the development of efficient catalysts are present in the literature.…”