Fabrication of phosphonium bamboo cellulose by triphenylphosphine: preparation, characterization, and adsorption of Acid Black 24.

Cellulose from bamboo shavings (BC) separated and modified by grafting triphenylphosphine, which was used as an adsorbent for the removal of Acid Black 24 from aqueous solution. The quaternary phosphonium-based bamboo cellulose (PBC) was characterized by FTIR and SEM measurements. The FTIR studies showed that the quaternary phosphonium group was successfully grafted onto the BC molecular structure. The effects of PBC dosage, contact time, initial dye concentration, temperature, and pH on the adsorption performance were studied. The nonlinear fitting kinetics and isotherms models were also conducted. The pseudo-second-order, intra-particle diffusion and Langmuir models were more suitable for analyzing the adsorption behavior of PBC for Acid Black 24 dye. The adsorption activation energy was lower than 40 kJ mol-1, and the ΔH0 value was in the range of 20~80 kJ mol-1, indicating that PBC played a dominant role in the physical purification of dye. The results of thermodynamic analysis indicated that the adsorption was a spontaneous endothermic purification process. Adsorbents had a good reusability and high adsorption performance for dye removal. The adsorbents PBC had a good reusability and could effectively remove residual Acid Black 24 dye with good development prospects in the field of biomass adsorbent materials.