Acetals play an important role in the growth of biofuel production. While performing their role as additives in improving the cetane index of biodiesel to facilitate quicker ignition, they also assist in improving its oxidation stability and bring down emissions of nitrogen oxides.
Engineer Ion Agirre, a researcher at the University of the Basque Country, performed a research on acetal known as 1.1 diethoxy butane and examined the system of reaction deployed to obtain it and suggested more efficient alternative methods.
He found that the use of traditional reactors in the diethoxy butane obtaining process often failed to achieve it due to low conversion efficiency and he found that apart from 40 to 50% of cases, the adaptation failed to take place even in kinetically agreeable temperatures. He researched two advanced systems to address the short comings of the thermodynamic restraints in conventional reactors.
First, he studied the reactive distillation method and found that it can increase the conversion efficiency by 40% to 50%. He utilized a semi-pilot type of plant and tried a number of variables such as feed configuration, reflux, reaction section height and others to achieve optimum conditions. He brought out a mathematical model based on the balanced stages of plant and authenticated it with experimental data.
In his second attempt, he used membrane reactors and found improvement in conversion efficiency by 40% to 70%. He utilized an irregular type of reactor and HybSi brand membranes for his research and tried a number of attempts on reaction of the dehydration membranes in separating water from diethoxy butane. He further developed two mathematical models such as discontinuous and continuous for validating the experiment and to design the process respectively.
For the purpose of research, Dr.Agirre had arranged a number of procedures at the industrial scale based on the results of dehydration membranes and on reactive distillation and completed the theoretical process and cost of estimation. He found that 1.1 diethoxy butane can be obtained efficiently by utilizing a mix of conventional distillation and dehydration membranes processes.