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ABSTRACT: In-situ catalytic upgrading of biomass fast pyrolysis vapors was performed in a fixed bed bench-scale reactor at 500°C, for catalyst screening purposes. The catalytic materials tested include a commercial equilibrium FCC catalyst (E-cat), various commercial ZSM-5 formulations, magnesium oxide and alumina materials with varying specific surface areas, nickel monoxide, zirconia/titania, tetragonal zirconia, titania and silica alumina. The bio-oil was characterized measuring its water content, the carbon-hydrogen-oxygen (by difference) content and the chemical composition of its organic fraction. Each catalytic material displayed different catalytic effects. High surface area alumina catalysts displayed the highest selectivity towards hydrocarbons, yielding however low organic liquid products. Zirconia/titania exhibited good selectivity towards desired compounds, yielding higher organic liquid product than the alumina catalysts. The ZSM-5 formulation with the highest surface area displayed the most balanced performance having a moderate selectivity towards hydrocarbons, reducing undesirable compounds and producing organic liquid products at acceptable yields.
Bioresource technology 06/2011; 102(17):8261-7. · 4.25 Impact Factor
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ABSTRACT: This research is focused on the recycling of three types of polymers, namely polycarbonate (PC), poly(acrylonitrile-butadiene-styrene) (PABS), and polystyrene (PS) from Waste Electric and Electronic Equipment (WEEE). Initially, the chemical structure of each polymeric material in a variety of WEEE was identified by Fourier Transform Infra Red (FTIR) spectroscopy and Differential Scanning Calorimetry (DSC). The potential recycling of these polymers from these wastes was examined by employing two different approaches, the dissolution/reprecipitation method and the more challenging technique of pyrolysis. During the first, the polymer is separated and recycled through a solvent/non-solvent system. It is a simple and economic technique leading to high recovery of pure polymer. Both, model polymers and plastic parts from WEEEs were studied and optimum experimental conditions, including dissolution temperature and time, polymer concentration and type of solvent were proposed to achieve significant recovery of the polymer (>90 wt %). Furthermore, pyrolysis of waste Compact Disks (CD) was investigated and compared with model poly(bisphenol A carbonate) (PC) through a laboratory-scale fixed bed reactor. The appropriate pyrolysis temperature was selected after measuring the thermal degradation of model PC by Thermogravimetric analysis (TGA). A large amount of oil was measured, together with a smaller amount of gaseous product, leaving also a solid residue. For both samples, the gaseous fraction consisted mainly of CO2 and CO whereas in the liquid fraction a large amount of different phenolic compounds, including the monomer bisphenol A, was measured. It seems that recycling of used CDs by pyrolysis is a very promising technique having the potential of producing useful high-value chemicals, which may find applications in the petrochemical industry. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Journal of Applied Polymer Science 06/2009; 114(1):212 - 221. · 1.29 Impact Factor
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ABSTRACT: The recycling of either model polymers or waste products based on low-density polyethylene (LDPE), high-density polyethylene (HDPE) or polypropylene (PP) is examined using the dissolution/reprecipitation method, as well as pyrolysis. In the first technique, different solvents/non-solvents were examined at different weight percent amounts and temperatures using as raw material both model polymers and commercial products (packaging film, bags, pipes, food-retail outlets). The recovery of polymer in every case was greater than 90%. FT-IR spectra and tensile mechanical properties of the samples before and after recycling were measured. Furthermore, catalytic pyrolysis was carried out in a laboratory fixed bed reactor with an FCC catalyst using again model polymers and waste products as raw materials. Analysis of the derived gases and oils showed that pyrolysis gave a mainly aliphatic composition consisting of a series of hydrocarbons (alkanes and alkenes), with a great potential to be recycled back into the petrochemical industry as a feedstock for the production of new plastics or refined fuels.
Journal of Hazardous Materials 12/2007; 149(3):536-42. · 4.17 Impact Factor
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ABSTRACT: The recycling of either model polymers or waste products based on low-density polyethylene (LDPE), high-density polyethylene (HDPE) or polypropylene (PP) is examined using the dissolution/reprecipitation method, as well as pyrolysis. In the first technique, different solvents/non-solvents were examined at different weight percent amounts and temperatures using as raw material both model polymers and commercial products (packaging film, bags, pipes, food-retail outlets). The recovery of polymer in every case was greater than 90%. FT-IR spectra and tensile mechanical properties of the samples before and after recycling were measured. Furthermore, catalytic pyrolysis was carried out in a laboratory fixed bed reactor with an FCC catalyst using again model polymers and waste products as raw materials. Analysis of the derived gases and oils showed that pyrolysis gave a mainly aliphatic composition consisting of a series of hydrocarbons (alkanes and alkenes), with a great potential to be recycled back into the petrochemical industry as a feedstock for the production of new plastics or refined fuels.
Journal of Hazardous Materials.
