The ester, butyl caprylate has wide applications in commercial market and it also possesses characteristic fruity flavor. The work exhibits the effect of various reaction parameters and the optimization study for the synthesis of butyl caprylate in presence of bio-catalyst. To achieve maximum conversion the optimum parameters thus established include; temperature 60 • C, mole ratio of caprylic acid and butanol as 1:2, lipase loading 2% (w/v), 250 rpm speed of agitation and 4g of molecular sieves. The immobilized enzyme was also recycled and reused for 7 cycles with only 30% loss from its initial activity. The thermodynamic parameters at different temperatures were also determined. The esterification was conducted successfully with 92% as maximum conversion in 5 h in a stirred batch reactor under solvent free system and in presence of molecular sieves that was used to adsorb water formed in reaction.

No abstract

This work illustrates the synthesis of cinnamyl propionate in the presence of lipase biocatalyst. The esterification reaction was performed in a solvent free condition with cinnamyl alcohol and propionic acid using fermase CALB™ 10000, a commercial lipase. Experiments were conducted to study different operating parameters such as enzyme loading, temperature, mole ratio, speed of agitation, and reusability of enzyme. Various kinetic parameters affecting esterification reaction were evaluated to synthesize cinnamyl propionate. It has been observed that the data obtained follows random bi-bi mechanism with inhibition by both acid and alcohol substrate. The highest conversion of cinnamyl propionate obtained is 87.89% after 7 h at optimum parameters: enzyme loading 2% (w/v), temperature 60 °C, acid to alcohol ratio 1:3, molecular sieves 6% (w/v) and agitation speed 200 rpm. Limitation of diffusion mass transfer between the enzyme surface and substrate does not show a significant effect on reaction kinetics. The study of repeated use of enzyme shows that it maintains 90% of its catalytic activity after six successive batches.

No abstract

Heat exchangers are used in a variety of industrial and technical settings. The design of heat exchangers is fairly sophisticated, since it necessitates an accurate study of heat transfer rate and pressure drop estimates, as well as considerations like as long-term performance and cost. Whenever heat transfer inserts are employyed, Along with the rise in heat transfer rate, the pressure drop increases as well. The pressure has risen.Energy conservation is critical for both industrial development and environmental impact reduction. Because of current energy prices, the need for energy conservation is rising. More resourceful gadgets can help reduce energy costs. In the refrigeration, automotive, chemical, and process sectors, heat exchangers are the most significant device. As a result, there is a demand in the industrial sector for heat exchangers that are less expensive, more efficient, and smaller. Inserts in channels are widely employed as part of a passive heat transfer augmentation technique.