Due to the growth in global demand for biodiesel, there is a tendency for the volume of its main by‐product, glycerol, available on the market to increase. This has led to a search for new uses for this by‐product and the development of new processes that use glycerol as a raw material because it has wide industrial applications. However, to be used in many of these processes, the glycerol must go through a purification stage before reaching the purity required for the application (which can reach 99.7% w/w). Taking this into account, the optimization of the parameters for the main glycerol purification stage (vacuum distillation) is essential to reduce the cost of this stage as much as possible. In this article, optimization of the vacuum distillation column was carried out using an artificial neural network (ANN) and a genetic algorithm (GA) together. With the optimization, it was found that four theoretical stages of equilibrium (separation) is the optimal value, in economics terms, for the distillation column on an industrial scale, leading to better performance (in terms of glycerol purity) than patents that used a smaller number of theoretical stages and an equal performance in relation to the patents that used a greater number of stages, which in this case reduces the cost with the size of the column. This result helps to increase the financially viability of using glycerol as a raw material, which can make several processes cheaper, thus generating greater added value to this sustainable by‐product.

Glycerol is the main by‐product of biodiesel plants, and new technological routes using it as a raw material are being developed due to the increased global production of biofuels. One possible application is in the production of acrylonitrile, a product with several industrial applications. Here, the production process of acrylonitrile using crude glycerol is proposed and analyzed. The process is shown to be economically viable, requiring an operating time of 5 years to achieve a net present value/investment ratio greater than 2 and an internal rate of return greater than 10 % per annum. The new process was found to be competitive compared to the current route (through propylene ammoxidation), supporting the development of new studies on this new route.

Article Highlights• Crude glycerol was used as raw material for the production of acrylic acid, substituting the propene • The study was carried out with the oxidative dehydration reaction in a single step • The process was economically feasible and produced glacial acrylic acid 98 mass% Abstract Glycerol is the main byproduct of industrial biodiesel plants, and new technological routes using it as feedstock have been studied, due to the increase in world biofuel production. One of the possible applications is in the production of acrylic acid, a product with several industrial applications. This study analyzed a new process of converting crude glycerol, through purification for the removal of impurities, followed by oxidative dehydration reaction in a single step and purification until glacial acrylic acid specification standards are met. It was attested that the process is economically viable, with a payback period of 5 years for an NPV/Investment greater or equal to 2 and an IRR greater or equal to 10% per annum, or 4 years in case tax incentives offered for the development of green technologies.

O objetivo do trabalho foi avaliar a viabilidade técnica e econômica da instalação de uma biorrefinaria integrada à indústria de laticínios para o uso de efluentes de soro de leite e produção do bioplásticopolihidroxibutirato (PHB) e proteína. Com base na literatura científica, as operações unitárias do processo de produção de PHB e proteína foram estabelecidas com o Simulador Aspen Plus versão 8.8. Cepas recombinantes de Escherichia coli foram utilizadas para a biossíntese metabólica de PHB com o solvente carbonato de propileno e ultrafiltração para extrair a proteína. Do ponto de vista técnico e econômico, a instalação de uma biorrefinaria integrada a uma indústria de laticínios que processa pelo menos 250.000 L de leite por dia é viável.

No abstract