Characterization and determination of lignin in different types of Iraqi phoenix date palm pruning woods

Abstract

This study aimed to find analytical data base for Iraqi phoenix date palm pruning woods, which produced by pruning process at the season of date palm production. Lignin has been extracted and purified for five types of Iraqi date palm using Klason lignin method. The weight of the extracted lignin ranged from 0.410 g to 0.720 g, and the lignin % ranged from 17.6 to 36. The other ingredients (waxes, oils, resin, and proteins of wood gums) % ranged from 20 to 29.5. FT-IR characterization showed that the (-OH) phenolic group appear in Ashrasi lignin structure only and disappear in other lignin samples, and the (4-O-5 inter monomeric lignin linkage) showed strong to moderate intensity peaks for all studied samples except the Austa omran sample has a weak intensity peaks. Also (DODO inter monomeric lignin linkage) showed strong intensity peaks for all studied samples except the Barban sample showed moderate intensity peaks. UV-vis characterization showed that the lowest absorption maximum (266 nm) corresponds to Barban lignin sample, while the highest absorption maximum (271 nm) corresponds to Sultani lignin sample.

Keywords: Characterization; Date palm pruning; Determination of lignin; Iraqi Phoenix dactylifera.