Biocomposite Adsorbent of Grafted Chitosan-benzaldehyde/<i>Lactobacillus Casei</i> Bacteria for Removal of Acid Red 88 Dye: Box-Benken Design Optimization and Mechanism Approach
Hasan M. Aghaa, Salis Auwal Musa, Ahmad Hapiz, Ruihong Wu, Khansaa Al‐Essa, Ali Mohammed Saleh, Abdallah Reghioua
Abstract
Herein, biohybrid biosorbent material was produced from grafting chitosan benzaldehyde/Lactobacillus casei (CHS-BZ/LAC) for the removal of anionic dye acid red 88 (AR88). CHS-BZ/LAC was fabricated using a hydrothermal process under the condition of 100 °C in an oven for 6 h. The optimization of AR88 dye adsorption by CHS-BZ/LAC was conducted by employing Box Bahnken design (BBD). The code and value of parameters used in this study were CHS-BZ/LAC dosage (A: 0.02-0.1 g/L), dye solution pH (B: 4-10), and contact time (C: 10-40 min). The BBD design shows that the highest removal of AR88 (94.5%) was achieved with the setting of CHS-BZ/LAC dose = 0.1 g/L, pH = 4, and contact time = 25 min. The suitability and the accuracy of the BBD design were confirmed by ANOVA analysis with the F-value = 112.84, and p-value < 0.0001. Dual interaction from parameters shows significant interactions of AB (CHS-BZ/LAC dosage vs pH), AC (CHS-BZ/LAC dosage vs contact time), and BC (pH vs contact time) with p-values less than 0.05. Multiple mechanisms of interactions took place in the biosorption process of AR88 by CHS-BZ/LAC such as n-π interactions, π-π attraction, electrostatic attraction, and hydrogen bonding. This study demonstrates the success of developing a new type of biosorbent (CHS-BZ/LAC) and effectively used for anionic azo dye removal from synthetic wastewater.