Abstract The use of carbon-based waste biomass in the production of plastics can partially meet the growing demand for plastics in the near future. An interest in the production of ethylene from bioethanol has been renewing, motivated mainly by environmental appeal and economics. The main objective of this work is the development of a mathematical model for simulation and optimization of the production of ethylene by the dehydration of ethanol, improving the performance of the process. The phenomenological model proposed is based on mass, momentum and energy balances for the process. The results obtained are satisfactory in comparison with theoretical results and experimental data found in the literature.

Foi descoberto que os fígados de peixes da região Amazônica possuem quantidades apreciáveis das vitaminas A, D e E, em paralelo com os valores padronizados para o óleo de fígado de Bacalhau. O óleo de fígado de tambaqui apresentou elevada concentração de vitamina A1 (retinol) e vitamina A2(dehidroretinol), enquanto que nos óleos de fígados do pirarucu e cuiu-cuiu ocorre, preferentemente, a vitamina A2. O teor em vitaminas D e E observado nos óleos de fígados de tambaqui e cuiu-cuiu foi extremamente alto.

It was found that fish livers from the Amazon have considerable amounts of vitamins A, D and E compared with the values of the standartized cod-liver oil. Tambaqui liver oil has high concentration of vitamin A1(retinol) and vitamin A2 (degidroretinol) whereas the liver oils of pirarucu and cuiu-cuiu have preferently the vitamin A2. The contents of the vitamins D and E observed in the liver oils of tambaqui and cuiu-cuiu was extremely high.