Research On Adsorption Characteristics Of Antimony In Water By Graphene Oxide/Sodium Alginate Double Network Hydrogel Bead

Antimony is a important natural resource in industry and play a irreplaceable role,meanwhile,that induced a series of antimony pollution in air,soil and water.Espcieal water antimony pollution,that counld threated human healthy directly.At present,many wastewater treatment methods applied to remediated antimony pollution waterbody,such as coagulate,membrane separation,bioremediation,adsorption,et al.Adorption get more and more focus,because of its high-efficiency and environment-friendly.Graphene oxide is ideal adsorbents that have vast specific suface area and enough mechanical strength,but that still some problem of easy to reunit and hard to solid-liquid separation.In this paper,the graphene oxide/sodium alginate double-network hydrogel beads has been prepapared that combine the advantages of both.Batch experiment and column experiment are applied to the reseach of GAD beads adsorption characteristics.The mechanism of GAD beads adsorb Sb?III?has been investigated by kinetics model fitting,adsorption isotherm fitting and thermodynamic parameters,and SEM,FTIR,XRD,Raman,BET,TGA are applied to profoundly research the physical and chemical propertis of GAD beads.According to the conclusion of SEM,FTIR,XRD and Ranman,the double-network hydrogel beads has been successfully prepared by preparation process,and a lot of hole structure on the surface of GAD beads could been observed that is benefit to the adsorption.As the TGA shows,the thermal stability and thermal conductivity of GAD beads have been enhancecd by introduced the graphene oxide.The specific surface area od GAD beads is 29.8m³/g and is three times than the single-network sodium alginate hydrogel beads by BET.In batch experiment,the adsorption performance of GAD beads has been investigated by a series experiment of pH,dosage,temperature,contact time,initial concentration,and co-exist ions.In the condition of pH=6 and the antimony concentration is 10 mg/L,the removal efficiency arrived at 81%by 400 mg adsorbents reacted in 50 mL antimony-contianing aquous solution for 240 min at 298 k.The chloridion and the sulfuric ion could not impct on the adsorption performance of GAD beads obviously,even in the chloridion and the sulfuric ion concentration of 1 M,the removal efficiency is still arrived at 68%and 52%respectively.Adsorption efficiency and adsorption stability have been enhanced after double-network formed.The physical and chemical propertis of GAD beads before and after reaction have been charaterazied by SEM and FTIR.In SEM,a lot of amourphous particle could been observed on the surface of GAD beads after adsorption reaction.In FTIR,the characteristic peak at 1083cm^-11 are disappeared and two new characteristic peak occurenced at 1249 cm^-1 some characteristic peak have been slight shifted after reaction.So the adsorption process persumaly consist of physical adsorption and chemical adsorption,and physical adsorption is donamit.Pseudo-first order,pseudo-second order and intra-partical kinetic model have been fitted with experiment data,the correlation coefficients of pseudo-second order is better than others,and above 0.99 in different initial concentration.Langmuir,Freundlich and Temkin adsorption isotherm are good fitted with the adsorption process?R²>0.90?.The maxmuim adsorption capacity of GAD beads is 7.67 mg/g at 298 k.the adsorption reaction is process of exothermic,entropy decreasing and spontaneous by conclusion of thermodynamic parameter.The regenerated experiment has been carried out by pure water,HCl,NaOH and CaCl₂,and the regeneration efficiency of 1 M CaCl₂ is better than others and arrived at 94%.The adsorption performance have no obviously decrease after five times adsoption-desorption experiment.According to the conclusion of column experiment,the leakage and penetration time is increasing with column height increasing,and decreaing with the intake velocity and initial concentration decreasing.Thomas and Yoon-Nelson model could been good fitted with the adsorption process of column.Above that,in this research,the GAD beads have good adsorption performance and recyclability,is a ideal adsorprion materials.