Nombre: DOUGLAS BITENCOURT VIDAL
Tipo: MSc dissertation
Fecha de publicación: 29/08/2017
Supervisor:
Nombre |
Rol |
|---|---|
| TAISA SHIMOSAKAI DE LIRA | Advisor * |
Junta de examinadores:
| Nombre |
Rol |
|---|---|
| ANA PAULA MENEGUELO | Internal Examiner * |
| KÁSSIA GRACIELE DOS SANTOS | External Examiner * |
| TAISA SHIMOSAKAI DE LIRA | Advisor * |
| THIAGO PADOVANI XAVIER | External Examiner * |
Resumen: 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.
