The Structure And Interface Control And Adsorption Properties Of Monolithic Multi-Stage Pore Carbonaceous Materials Based On Sodium Alginate

With the rapid development of traditional industry,the water pollution problem has gradually attracted the public attention.Water pollution can be traced to the wastewater from the printing and dyeing industry.In recent years,there have been serious water-pollution incidents caused by improper treatment of wastewater containing dyes,not only a serious threat to the natural environment,also has potential threat to people’s health.Therefore,removing MB-containing wastewater to an acceptable level prior to discharging into the natural system is critical.Therefore,the preparation of economic and non-polluting bio-based adsorption materials for the removal of dyes is a very meaningful work.In the present study,through a series of chemical methods,including carbothermal reduction and oxidation treatment,make it contains significant amounts of both oxygen-containing functional group and the specific surface area.A type of porous bio-sorbent that can proficiently adsorption dye from aqueous solution was prepared by directly utilizing sodium alginate as the basic raw material.The specific research work is as follow:1.First,a certain amount of calcium carbonate and sodium alginate will be doped,and the hydrogel bead will be obtained with Ca²⁺crosslinking.As precursor,and use of calcium carbonate for pore-forming agents by carbothermic reduction and oxidation treatment,preparation with tailored hierarchical structure and regulation of monolithic adsorbent oxygen-containing functional groups（CaCO₃/CA-ox）.The static and dynamic adsorption properties of methylene blue were discussed systematically.The experimental results showed that the CaCO₃/CA-ox Langmuir maximum adsorption capacity for MB was 397.9?8.3 mg/g.CaCO₃/CA-ox could not only rapidly improve the adsorption capacity for the removal of MB,but also exhibited higher adsorption rate for methylene blue compared to that of sodium alginate.Furthermore,compared to traditional powdery materials,this new porous adsorbent is very convenient for column adsorption and large-scale for practical applications,due to the simple regeneration and reusability.2.Use the aforementioned precursor,the contained CaCO₃ calcium alginate hydrogel beads were left for 24 h to complete solidification.After 24 h immersion,the beads were taken out and subsequent washed by acid treatment and freeze-drying,it has a fast adsorption and easy recovery of bio-based materials（ABH-1:3）.The influence of contact time,pH,initial concentration and flow rate on the removal of MB were investigated.Moreover,the isothermal adsorption,kinetics and potential removal mechanism were discussed systematically.The results revealed that the maximum adsorption capacity of was as high as1426.0 mg/g for ABH-1:3.A high pH value is beneficial for the removal of MB;The adsorption reaction was effectively facilitated,and achieve adsorption equilibrium was significantly shorter than that of raw alginate.More significantly,the uptake capacity of ABH-1:3 was still higher than 75%of the maximum adsorption capacity even after ten cycles;Besides,the fixed bed experiment showed that the adsorption capacity of MB decreased with the flow rate of solution increasing.Overall,it indicating that this novel absorbent can be considered as a promising adsorptive material for removal of MB from aqueous solution under batch and continuous systems.3.The prepared adsorbents were characterized by SEM,TEM,FTIR,nitrogen adsorption/desorption、XRD、XPS、UV-vis and PH.