响应曲面法优化Fe(Ⅲ)改性卡氏变形杆菌吸附去除Sb(Ⅴ)及其机理

Environmental pollution caused by excessive Sb(Ⅴ) in the water environment has attracted more and more attention. We investigated the effect and mechanism of Sb(Ⅴ) removal by an iron salt-modified biosorbent (Fe(Ⅲ) modified Proteus Cibarius adsorbent (FMPAs)). We evaluated the optimization of adsorption time, adsorbent dose, pH, temperature and initial concentration of Sb(Ⅴ). We used response surface methodology to remove Sb(Ⅴ) in synthetic wastewater through FMPAs. The optimal conditions were determined and the adsorption isotherm model, the adsorption kinetics model and the adsorption mechanism were also evaluated. The results showed that: (1) The optimal conditions for the adsorption of Sb(Ⅴ) by FMPAs were adsorption time 3.0 h, adsorbent dose 1910.04 mg/L, pH 2.31, temperature 45.0 ℃ and the initial concentration of Sb(Ⅴ) 24.80 mg/L; the removal rate of Sb(Ⅴ) reached 97.03% at the optimal conditions. (2) The adsorption process of Sb(Ⅴ) by FMPAs conformed to the Langmuir adsorption isotherm model, and the maximum adsorption capacity (q_max) was 60.506 mg/g; The pseudo-first-order kinetic model provides a good fit to the adsorption process, and the adsorption process can be classified as a single layer adsorption and chemisorption. (3) The adsorption was via the hydroxyl group in Fe-O-OH and EPS-Polyose-O-Fe(OH)₂ which formed a new complex Fe-O-Sb, thereby removing Sb(Ⅴ). The study showed that FMPAs have a high adsorption capacity for Sb(Ⅴ). It is a green adsorbent and has great potential for the treatment of Sb(Ⅴ)-containing wastewater.