Extraction and characterization of humin from Jordanian soil


  • Safa’a Al-Momani
  • Fawwaz Khalili


The aim of this study is to separate and characterize humin from two locations in Jordan: Azraq Oasis (Inceptisols) and Ajloun forest (Vertisols) soils for the first time. Humin from those soils has been extracted and purified. They were characterized by FTIR, elemental analysis, TGA, SEM, XRD, solid and 13C NMR. Also surface area, porosity and cation exchange capacity were determined. The Azraq humin has higher carbon percent that indicated high condensation than Ajloun humin. Also Azraq humin has higher ash percent due to presence of Kaolinite and Bentonite. The O/C ratio of Ajloun humin is higher than for Azraq indicating that is richer in polar groups, and may reflect larger amount of carboxylic acid, phenolic and O-alkyl groups. The C/N ratio of Ajloun humin is lower than for Azraq which indicates that Azraq humin is in more advanced stage of humification. From 13C NMR the aliphatic and aromatic percent were higher in Ajloun humin, but the carboxylic and carbonyls were lower than in Azraq humin. The SEM micrograph shows the layer structure (sheet) present; with high porosity. The cation exchange capacity values were 145.40 meq/100g and 56.65 meq/100g, for Azraq and Ajloun humin, respectively. Most pores radii are in the range of micropores and some of these in range of mesopores and macropores in the two humin.