Long term storage of biodiesel/petrol diesel blends in polyethylene fuel tanks

Effect of Biodiesel on Biofilm Biodeterioration of Linear Low Density Polyethylene in a Simulated Fuel Storage Tank

“…The inoculum was obtained during the spring of 2012 by Imperial Oil Ltd., in their facilities in Sarnia, ON. The diesel fuel was a low sulfur, summer grade purchased from local gas sta tion and the biodiesel was supplied by a biodiesel pilot plant at the University of Guelph (Ridgetown site, ON); characterization of the biodiesel fuel was included in an earlier paper [5]. Fuel, culture media and the cut slabs of polymer were sterilized before inoculation.…”

“…Among the materials used in fuel infrastructure, polyethylene is of particular importance because it is heavily used in the manufacture of storage tanks. In the presence of biodiesel, fuel storage tanks made with this polymer occasionally experience ' losses in their mechanical properties that are not fully understood at present [5], Fuel adsorption into walls and/or microbial activity due to water accumulation in tanks has been hypothesized to explain losses in mechanical properties associated with polyethylene [1, [5][6][7][8], Microorganisms have been found to flourish both in the interphase between fuel and water layers as well as in biofilms attached to the walls of tanks [8][9][10], It has been found that the presence of a biotic phase in contact with polyethylene can lead to losses of mechanical stability, topography of fashioned parts, as well as changes in crystallinity, molecular weight and chemistry of the polymer [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26], The bio chemical pathways involved in such damage to polyethylene are not completely known; however, it is clear that oxidation of its chains is a fundamental step required to accelerate the use of this substrate by microorganisms [27,28]. The resemblance of polyeth ylene to paraffins can imply that once the molecular weight of the polymer has been reduced to a range in which enzymes involved in alkane degradation are active (typically 5 to 50 carbons) [29] then the biochemical reactions involved in hydrocarbon metabolism may lead to polyethylene degradation.…”

Avaliação de características de biodieseis de fontes alternativas submetidos a condições de armazenagem diferenciada

“…16 O biodiesel é muito sensível à exposição ao ar e à luz, a temperaturas elevadas, à presença de traços de metais com ação catalítica à oxidação, pigmentos, quantidade de insaturações e até mesmo o recipiente no qual o combustível é armazenado pode estar relacionado com a preservação das suas propriedades originais. 11,[17][18][19][20] Atualmente, a conservação do biodiesel é realizada por meio da adição de antioxidantes sintéticos ou naturais, os quais mantêm as propriedades desse biocombustível dentro das especificações. Uma ampla variedade de antioxidantes já foi testada e tem produzido resultados promissores na garantia da integridade das moléculas de éster.…”

“…[21][22][23][24][25] Nesse contexto, vários pesquisadores vêm conduzindo estudos relacionados à estabilidade de biodiesel para identificar os fatores que provocam sua oxidação, aperfeiçoar os métodos de avaliação da estabilidade oxidativa, bem como aprimorar a rota de síntese e as condições de estocagem, na tentativa de manter a qualidade do combustível. 11,16,[18][19][20][25][26][27][28] A degradação do biodiesel pode ser identificada por meio de alterações nas suas propriedades, tais como o índice de acidez, índice de peróxido, teor de ésteres e índice de iodo, além da viscosidade, densidade, número de cetano e poder calorífico. 29 Outros indicadores de deterioração dos biocombustíveis estão associados à sua coloração e à presença de produtos de oxidação que podem ser corrosivos ao motor e inclusive levar ao entupimento das bombas e filtros de injeção devido ao aumento da viscosidade.…”

The effects of e‐beam crosslinking of LDPE on the permeation of hydrocarbons

“…This polymer is readily available and processible at relatively low costs. 3 To improve the permeation properties of the polymer, a surface modification by sulfonation or fluorination has been demonstrated. 1 Highdensity polyethylene (HDPE) has been the preferred material for lining applications for crude-oil onshore and inland transport at higher temperature and pressure.…”