Characterization of pyrolysis products from end-of-life electronic equipment [electronic resource] /
Characterization of Pyrolysis Products from End-Of-Life Electronic Equipment
Venkatadri E. Thiruvallur
Tertiary Recycling of End-of-Life electronic equipment such as computer monitor casings
and disk drives is considered in this project. This research aim's at finding new recycling
processes that have a possibility for economic scale-up. The present work was divided into two
parts. The first one dealt with the investigation of two mixed-plastics streams provided by MBA
Polymers (MBAP). One of the streams consisted of fines (MBAP-1), and the other was a nonseparable
stream, MBAP-2. These solid polymer streams from MBAP were reacted in a Tubular
Reactor inerted with helium. The overall objective of these reactions is to determine the process
parameters (Reaction Temperature and Pressure) required in order to achieve maximum oil yield.
The reaction process parameters are the reaction temperature (375 °C, 400 °C, 425 °C and 450
°C) and the reaction time (15min, 30min and 45min). Tetrahydrofuran (THF) and hexane are used
as solvents to separate the non-gaseous products which are partitioned into THF-Insoluble, THF-
Soluble Hexane-Insoluble and Hexane-Solubles while the gaseous products are analyzed using a
gas chromatograph (GC).
Adherent Technologies, Inc. (AT) uses a two-stage catalytic pyrolysis process. In the
second part of the present work, the liquid after pyrolysis by AT but before upgrading was
analyzed by studying the boiling-point curves obtained using ASTM D-86 atmospheric distillation
and ASTM D-2887 simulated distillation methods. The objective of these distillation runs is to
determine the percentage of feed in the diesel fuel range (340-640 °F).
For MBAP-1, the optimum reactor conditions (which maximize the production of the oil
fraction) are 425ºC for 15 min. The oil yield at this condition is found to be 62%. For MBAP-2, the
optimum reactor conditions are 425ºC for 30 min. The oil yield at this condition is found to be
65%. Atmospheric distillation following the ASTM D-86 procedure, verified further with simulated
distillation following the ASTM D-2887 procedure, indicated that 65-70 % of the AT-1 oil and
MBAP-2 product oil fraction was in the diesel fuel range. Presence of halogenated species
(bromides and chlorides) poses a challenge for the AT oil to be used in the petroleum industry.
The gas yield from pyrolysis of the MBAP-1 and MBAP-2 mixed-plastic samples was found to be
very low (1-8%) but the gas composition and heat recovery calculations reveal a very high fuel
value (5,900-15,500 BTU/lb.) and available heat recovery (6.66 – 19.19 MMBTU/hr). The product
gas could contribute significantly as a source of heat during the pyrolysis process. Coke analysis
for MBAP and AT-1 samples revealed very poor coking values that required no further
assessment. However, ash content analysis of MBAP and AT-1 oil revealed an ash content of
less than 0.2%, an important requirement to be classified as a diesel fuel.
School:West Virginia University
School Location:USA - West Virginia
Source Type:Master's Thesis
Keywords:waste electronic apparatus and appliances computers plastics
Date of Publication: