Remoção de corantes sintéticos de efluentes aquosos usando Onecarpus bacaba Mart como bioadsorvente

Abstract

In this work the plant product Onecarpus bacaba Mart. in natura (OBMi) and modified (OBMm) in 3 molar NOH alkaline medium, was used as a biosorbent to remove Rhodamine B (RB) and Methylene Blue (AM) dyes from synthetic effluents. The in natura and modified fibers presented an amorphous structure. OBMi and OBMm were characterized by Boehm titration and determination of the point of zero charge (pHPCZ). The influence of the factors, pH of the system, contact time, mass of the adsorbent and the concentration of the dye Methylene Blue (AM) and Rhodamine B (RHB), was studied by experiments performed in batches. The best amount of adsorbent was 200 mg. The preliminary study of adsorption kinetics and isotherm models revealed that the adsorption process was best fitted by pseudo-first order and Langmuir model, respectively. The maximum adsorption capacity was better presented for OBMm with both AM and RB. The obtained results show that the OBM biosorbent can be applied as a low cost adsorbent for the removal of RB and AM from effluents, since it presented good adsorption capacity when compared to other biosorbents, the modified adsorbent presented a significant improvement in relation to to in natura fibers, where the removal percentage was around 40%, with the modification these values reached 80% of fiber removal.