Preparation Of Alcohol/Phenolic Hydroxyl Modified Biomass For The Separation And Adsorption Of Germanium

In this thesis, Persimmon leather and shell crab as the raw material, and go by a simple process and modification, We have prepared several types of green pollution-free adsorption agents. and then the separation and adsorption of Ge(IV) with adsorbents were investigated systematically.First of all, Persimmon leatherwas modified by cross-linking agent concentrated sulfuricacid, formaldehyde, which named APF and CPT respectively. APF, CPT characterized by boehm titration method SEM and BET to analyse surface functional groups and morphology, the APF gel showed a high affinity for Ge(IV) comparing with CPT gel. and the maximum adsorption capacity was evaluated as 58.71,42.32 mg/g in case of pH 10. The adsorption process of absorb germanium fitted Langmuir isotherm model. Additionally, the adsorption process followed pseudo-second order kinetics. The APF gel was characterized by FTIR, XPS, which was confirmed as adsorption mechanism is ion exchange reaction. And separation Ge (IV) from the Ge(IV)-As(Ⅲ) mixtures solution, investigate the practice application for APF gel.Secondly, CS was modified by Diethanolamine, glycol, which named HEMA-IDOI-CS, CCTS-DPA respectively. By infrared/boehm titration method SEM and BET to prove successful modified, and the maximum adsorption capacity was evaluated as 74.21 and 23.92 mg/g case of pH 4. and the other mentalions such as Cu(II), Fe(III), Zn(II), Mn(VII) didn’t show the adsorption.In addition, investigated the thermodynamics, kinetics and adsorption mechanism of the HEMA-IDOI-CS gel. And through the adsorption elution cycle experiment, show the stability and practicability of the adsorbent.In order to adsorb germanium ions at acidic conditions, CS was modified by three kinds of phenol, which named THB-CS, HBD-CS and PTD-CS respectively. The maximum adsorption capacity of THB-CS for germanium in case of pH=1, while not absorb other metal ions. Kinetic adsorption process followed pseudo-second order kinetics. By FTIR, XPS analysis the adsorption mechanism is ion exchange reaction.Use 3% NaOH as analytical agent, after three adsorption elution cycle experiments, the recovery of germanium by THB-CS gel can also reach 80%.