2010 CORROSIVITY OF ANHYDROUS ETHANOL, HYDRATED ETHANOL (1) AND FUEL E25 (2) (25% ETHANOL/75% GASOLINE) Anna Ramus Moreira, Zehbour Panossian, Célia A. L. Santos and Gislaine M. Bragagnolo IPT Institute for Technological Research São Paulo – Brazil anna@ipt.br Marcelo C. Gandur and Emerson Monteiro de Souza Corrosion Protection Products – Building Safety Solutions - 3M Brazil ABSTRACT The objective of the work was to study the corrosion of API 5LX 46 and API 5LX 65 alloys, used for pipelines, in anhydrous ethanol, hydrated ethanol and fuel E25 through laboratory immersion tests, NACE TM-0172 tests and dynamic tests (corrosion loops). Based on the results of this study, it was concluded that it is advisable that the internal surface of hydrated ethanol storage tanks be painted in order to avoid the corrosion of the internal walls which, despite being incipient, determines color changes which is unacceptable in the market. Furthermore, in pipelines used only for ethanol transportation, the painting of the internal walls of the tubes is not necessary because both the anhydrous ethanol and the hydrated ethanol are not aggressive to the steel, as long as the relative movement of the liquid is guaranteed. Finally, in pipelines used for ethanol and for petroleum derivatives transportation, it is advisable that the internal surfaces of these pipes be painted in order to avoid the contamination of the ethanol (anhydrous or hydrated) which makes the ethanol aggressive to the steel and changes its color (unacceptable in the market). Keywords: biofuel, biofuel corrosivity, ethanol, E25, pipeline, storage tank. 1 Hydrated ethanol is the ethanol fuel commercialized in Brazil: ethanol with a maximum content of 7% (m/m) of water. 2 In Brazil, the amount of ethanol that is added to the gasoline is fixed by the Government as 25 %. The “Brazilian gasoline” blend is known in the United States as fuel E25. ©2010 by NACE International. Requests for permission to publish this manuscript in any form, in part or in whole, must be in writing to NACE International, Publications Division, 1440 South Creek Drive, Houston, Texas 77084. The material presented and the views expressed in this paper are solely those of the author(s) and are not necessarily endorsed by the Association. 1 Paper No. 10078 Michael Billingham - Invoice 208821 downloaded on 5/13/2021 9:17:26 AM Single-user licence only, copying/networking prohibited