Síntese sustentável de biofluido com perspectivas de utilização em transformadores de potência

Abstract

One of the most challenging problems that society will face in the coming years is the impact of climate change. Due to the growing concern about the future, the continuous search for ways to overcome the global environmental crisis has become indispensable and, therefore, several actions are being carried out worldwide to reverse this situation. Because of the current scenario, there has been intense interest in ecologically friendly disruptive innovations that are particularly important in the development of electrical power machines (EPM), such as the power distribution transformer (PDT). PDTs use dielectric fluids to cool the equipment, such as insulating mineral oil (IMO). From an environmental perspective, due to the numerous disadvantages of using IMO, efforts have been made regarding the search for alternative insulating fluids. Insulating liquids from vegetable oils (VO) are considered reliable substitutes for IMO and are a relevant approach to promoting sustainability. Given this context, this work intends to perform molecular modifications in babassu coconut oil (BCO) to obtain an environmentally friendly insulating biofluid for use in PDTs. For this purpose, lipase (LIP) encapsulation was performed in hyperbranched polyglycerol (HPG) microcapsules using microfluidic technology. The HPG-LIP microcapsules were characterized by the following techniques: SEM, ATR-FTIR and TGA. The optimization of the microfluidic cell parameters for immobilization of LIP was carried out by artificial neural network (ANN). The resulting HPG-LIP microcapsules are spherical and have an average diameter of 29 mm with monomodal size distribution. The optimum conditions determined by ANN were: HPG concentration of 10% (wt), LIP loading of 20% (wt) and total flow rate in the microfluidic cell of 1.0 mL/h. Under these conditions, the maximum capacity of the LIP that can be microencapsulated is 85%. The apparent Km and apparent Vm´ ax of the HPG-LIP were 1.138,14 mM and 0.49 U/mg, respectively. The reusability of HPG-LIP showed 81.5% of the activity retained even after 10 cycles. Based on the results obtained, microfluidics guided by RNA could be useful to produce HPG-LIP microcapsules for applications in biotechnology. Thus, the prepared microcapsules were used as enzymatic biocatalysts in the synthesis reactions to obtain the BCO-based insulating biofluid in a batch reactor.