Remediation of water tainted with noxious aspirin and fluoride ion using UiO-66-NH₂ loaded peanut shell

One green adsorbent, UiO-66-NH₂ modified peanut shell (c-PS-MOF), was prepared in a green synthetic route for improving the capture level of aspirin (ASP) and fluoride ion (F^-). The adsorption properties of c-PS-MOF were evaluated by batch experiments and its physicochemical properties were explored by various characterization methods. The results showed that c-PS-MOF exhibited a wide range of pH applications (ASP: 2-10; F^-: 3-12) and high salt resistance in the capturing processes of ASP and F^-. The unit adsorption capacity of c-PS-MOF was as high as 84.7 mg·g^-1 for ASP as pH = 3 and 11.2 mg·g^-1 for F^- under pH = 6 at 303 K from Langmuir model, respectively. When the solid-liquid ratio was 2 g·L^-1, the content of ASP (C₀ = 100 mg·L^-1) and F^- (C₀ = 20 mg·L^-1) in solution can be reduced to 0.48 mg·L^-1 and 1.05 mg·L^-1 separately. The recycling of c-PS-MOF can be realized with 5 mmol·L^-1 NaOH as eluent. Analysis of simulated water samples showed that c-PS-MOF could be used to remove ASP and F^- from actual water. The c-PS-MOF is promising to bind ASP and F^- from rivers, lakes, etc.