The highest char yield (CY) was obtained from Prosopis juliflora (45.23 %) while the other species produced good CY (35.83 to 40.36%). The CY was directly related to total extractives (TE), alcohol-benzene extractives (ABE), lignin contents or specific gravity (SG) of wood. The higher apparent density (AD) of char was obtained from Prosopis juliflora, Eucalyptus microtheca and Citrus sinensis (0.581, 0.549 and 0.533 g/cm 3 , respectively) and depended on SG of wood. The volumetric shrinkage (VS) of char ranged from 35.01 to 61.52 % fpr Prosopis juliflora and Casuarina cunninghamiana , respectively and was inversely related to SG, TE or ABE of wood. Further, Prosopis juliflora had the higher gross heat of combustion (GHC) of char (7673 cal/g) while Ficus retusa and Acacia ampliceps had the lower values (6844 and 6887 cal/g, respectively). The GHC of char was related directly to fixed carbon (FC) and inversely to ash contents of char.
Most of the species used had the highest VM content of char (26.30-27.61 %) except for Acacia ampliceps char that it had a minimum VM. The higher FC content of char was obtained from Prosopis juliflora , Casuarina cunninghamiana and Citrus sinensis (69.23, 68.98 and 68.69 %, respectively). Contrarily, Ficus retusa, Acacia ampliceps and Psidium guajava contained the lower FC contents of char (64.48, 64.63 and 65.17%, respectively).
The ten wood species produced good charcoal for domestic purposes in considerable yields. Prosopis juliflora produced charcoal with the highest CY, AD, GHC and the lowest VS and ash content. If the FC content is readjusted by production at higher temperatures, it can be considered as an ideal raw material for industrial purposes.
The yield of NLTD ranged from 20.37 to 30.64% while its GHC ranged from 3658 to 4923 calories/g for Eucalyptus camaldulensis and Ficus retusa , respectively. Prosopis juliflora had the highest yield of water scrubber distillate (3.93 %) while the lowest value was from casuarina. Further, the species were similar in their NG yield (28.38 to 38.360/0).
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The phenolics content in methylene chloride fraction (MCF) differed between 73.01 and 7.98% for Eucalyptus camaldulensis and Psidium guajava, respectively. Syringol with the highest yield and guaiacol were detected in all MCF of the ten species except for Malus domestica and Psisium guajava that were free of guaiacol.
Limonene was detected in five species while cresols were found in all species except for Psidium guajava and the two species of casuarina. The content of aromatics other than phenolics differed from 48.01 to 6.76% for Casuarina cunninghamiana and Eucalyptus camaldulensis, respectively. The 2,3,5-trimthoxytoluene, 1,2benzenedicarboxylic acid [bis( ethyl-hexyl ester) or diisoctyl] and 1- or 2-ethyldiphenylmethane presented frequently in most species. The heterocyclics content ranged from 31.12 to 4.53 % for Eucalyptus microtheca and Casuarina glauca , respectively in which 3-acetyl-6methyl-5H-pyran-2, 4-(3H)-dione was the most appearance. The aliphatics content in the MCF differed between 80.14 and 2.42 % for Pisidium guajava and Acacia ampliceps, respectively in which hexadecanoic acid was the most presence.
The recoveries of the major phenolic derivatives of the MCH such as syringol and guaiacol may become economically attractive from the higher species containing them specially Eucalyptus camaldulensis, Prosopis juliflora, Acacia ampliceps, Citrus sinesis . However, other phenolics can also be regarded.
Since both species of casuarina had the highest content of the aromatics other than phenolics, they are good sources for 2,3,5trimethoxytouene and 1,2-benzenedicarboxylic acid [bis (2-ethylhexyl ester) or diisoctyl).
Due to the highest heterocyclics contents in Eucalyptus Microtheca and Malus domestica , the predominant heterocyclic 3-acetyl-6methyl-5H-pyran-2,4-(3H)-dione can be recovered from their MCF. Also, this eucalypt may be a good source of methylimino-3-methyl2,3,4,5,6,7-hexahydrobenzothiazole and apple is the best raw material containing methylthiobenzene among the species studied. Further, for the aliphatic compounds, Psidium guagava was the highest feedstock for aliphatic acids specially hexadecanoic and cis-9-octadecenoic acids.
