Estudo da influência das condições de pirólise de compósito de PEBD/Al na produção de hidrocarbonetos

• Autor(a) principal: Vidal, Douglas Bitencourt
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/8445
• topic: Cardboard packaging; Pyrolysis; Low density polyethylene; Embalagens cartonadas; Polietileno de baixa densidade; Engenharia/Tecnologia/Gestão; Alumínio nas embalagens; Pirólise; Reciclagem - Indústria; 620.9

The disposal of carton packs has become an environmental liability as its consumption increases. One way to take advantage of this material is by the paper disintegrator, which results in the formation of the polyethylene and aluminum composite (LDPE/Al). Able to separate the aluminum from the polyethylene present in the composite, pyrolysis is a technique used mainly in the recovery of underutilized materials, generating products of interest. In this context, the general objective of this work was to study the conditions of the LDPE/Al pyrolysis process. The experiments occurred at temperatures 813, 853 and 893 K and heating rates of 10, 30 and 50 K min-1 . The influence of temperature and heating rate on the pyrolysis of the LDPE/Al composite in fixed bed was analyzed in order to estimate the effects of these process variables, as well as to identify the products obtained. Initially, thermogravimetric analyzes demonstrated that the degradation of this material starts at 670 K and becomes complete at 820 K. When comparing the derived thermogravimetry (DTG) of the LDPE/Al with that of the pure polyethylene, it was noticed that the two curves were overlap, demonstrating that aluminum does not interfere with reactions. From the data of thermogravimetry and isoconversion kinetic models, the overall activation energy of the PEBD / Al pyrolysis reaction was estimated: 169.61 kJ.mol-1 (Ozawa), 170.79 kJ.mol-1 (KAS), 181.33 kJ.mol-1 (Starink) and 205.87 kJ.mol-1 (Kissinger), these values being similar to those found in the literature for pure polyethylene. After analyzing the yields of the products, there was a greater participation of condensates, of which the olefins presented a more pronounced production in 893 K. It was also observed that the temperature had a greater influence on the yield of condensed products than the rate of heating. With respect to the composition of the olefins for the reactions at 893 K, mainly aliphatic compounds, such as the alkenes, of carbonic chain of C12 to C20 were identified. Because it is formed predominantly of polyethylene, the pyrolysis products of the composite result in hydrocarbons that can be used as raw material by the industry.