Biochar loaded chitosan/gelatin/poly(ethylene glycol) biocomposite beads: Morphological, thermal and swelling properties

Abstract

The chitosan/gelatin/biochar biocomposite beads were prepared via the use of the emulsion crosslinking method in the presence of poly(ethylene) glycol as a cross-linker. The effects of different ratios of biochar (1 and 5%) on the characteristics of the beads were evaluated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA) and Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR) and swelling studies. The FT-IR results showed the interactions of biochar and polymer matrix. The prepared beads showed good swelling properties and different morphologies. The average diameter of neat chitosan/gelatin beads was almost 725 µm, while the average diameter of 1% and 5% biochar incorporated beads were 726 µm and 597 µm, respectively. The swelling capacity of the beads was decreased from 4671% to 2092% when the biochar incorporation ratio increased from 1% to 5%. This indicated that the preparation of beads with varying properties can be achieved by controlling the biochar amount. The beads may be evaluated in various applications as polymeric carrier systems and adsorbents.