Granules of waste tires were pyrolyzed under vacuum (3.5 to 10 kPa) conditions, and the effects of temperature and basic additives (Na2CO3, NaOH) on the properties of pyrolysis were thoroughly investigated. It was obvious that with or without basic additives, pyrolysis oil yield increased gradually to a maximum and subsequently decreased with a temperature increase from 450 deg C to 600 deg C, irrespective of the addition of basic additives to the reactor. The addition of NaOH facilitated pyrolysis dramatically, as a maximal pyrolysis oil yield of about 48 wt% was achieved at 550 deg C without the addition of basic additives, while a maximal pyrolysis oil yield of about 50 wt% was achieved at 480 deg C by adding 3 wt% (w/w, powder/waste tire granules) of NaOH powder. The composition analysis of pyrolytic naphtha (i.b.p. (initial boiling point) ~205 deg C) distilled from pyrolysis oil showed that more dl-limonene was obtained with basic additives and the maximal content of dl-limonene in pyrolysis oil was 12.39 wt%, which is a valuable and widely-used fine chemical. However, no improvement in pyrolysis was observed with Na2CO3 addition. Pyrolysis gas was mainly composed of H2, CO, CH4, CO2, C2H4 and C2H6. Pyrolytic char had a surface area comparable to commercial carbon black, but its proportion of ash (above 11.5 wt%) was much higher.
Vacuum pyrolysis of waste tires with basic additives
Waste Management ; 28 , 11 ; 2301-2310
2008
10 Seiten, 8 Bilder, 8 Tabellen, 17 Quellen
Aufsatz (Zeitschrift)
Englisch
Plasticizing properties of heavy oils obtained from vacuum pyrolysis of used tires
Kraftfahrwesen | 1996
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