Lignin and holocellulose from coir pith involved in trimethylamine (fishy odor) adsorption.

Coir pith is a highly potential adsorbent for adsorbing trimethylamine (TMA). It harbors a higher adsorption capacity for TMA compared to commercial activated carbon (CAC). It was found that lignin and holocellulose extracted from coir pith played an important role in TMA adsorption. Lignin itself had the highest TMA adsorption capacity (269.01 mg/g) followed by holocellulose (75.43 mg/g), coir pith (14.3 mg/g) and CAC (10.26 mg/g), respectively. The pseudo-first- and second orders were applied to the kinetic data. For the adsorption of TMA by coir pith, the best fit was achieved by the pseudo-second order. Thermodynamic studies showed an endothermic and physico-chemical adsorption process between TMA and the coir pith. TMA desorption study suggested that only 14%-47% of TMA was desorbed with distilled water. In addition, Fourier transform-infrared (FT-IR) spectra showed that C-H bond (methyl group), C-O bond from phenolic alcohol and C-O bond from tertiary alcohol in lignin and holocellulose were involved in TMA adsorption. Coir pith-based filter showed high TMA adsorption efficiency (98%) and kept constant for more than 48 days in a continuous system. Pilot scale experiment, coir pith beads filter could be succesfully applied as a packing material for TMA removal. Therefore, coir pith can be used as a promising packing material for TMA treatment at contaminated site.

Modified coir pith with glucose syrup as a supporter in non-external nutrient supplied biofilter for benzene removal by Bacillus megaterium.

Coir pith glucose syrup beads were used as a supporter in a biofilter system. The modified coir pith beads provided a carbon source and controlled humidity for microorganism growth for long-term operation without external nutrient supplementation. For the screening, Bacillus spp. were immobilised on coir pith beads and used for benzene bioremediation. The result showed that coir pith beads immobilised with Bacillus megaterium can remove on average 85-100% of the benzene (215-day operation). In addition, B. megaterium presented the ability to transform benzene to catechol. For an up-scaled application, a 25-L biofilter system was developed and tested in a closed 24-m3 container re-injected with 0.6 ppm benzene for 8 cycles. The system presented the ability to remove 100% of the benzene. This biofilter has the potential to be applied in a real benzene-contaminated site.