Preparation Of Sodium Alginate-based Composite Adsorbent And Its Adsorption Of Heavy Metal Ions

In recent years,with the rapid development of modern industry,the pollution of heavy metal wastewater has gradually attracted people's attention.Heavy metal pollutants are difficult to control.This pollution not only affects the ecological environment,but also poses a serious threat to human health through the food chain.Therefore,how to effectively treat heavy metal ions in wastewater has become a hot spot in the field of water treatment.In this paper,the purpose of synthesizing and preparing green,high-efficiency and low-cost heavy metal ion wastewater adsorbent is as follows:1.Using sodium alginate and melamine as raw materials,a green environmentally friendly sodium alginate-melamine?Alg-Mel?composite gel adsorbent was prepared by one-step synthesis to remove Pb²⁺from water.The experimental results show that the prepared Alg-Mel has higher affinity and selectivity for Pb²⁺,the adsorption rate of Pb²⁺in aqueous solution is 95.4%,and the maximum adsorption amount of Pb²⁺is 287.7 mg/g,which is much higher than most.The amount of adsorption of the lead ion adsorbent.In addition,Alg-Mel sorbent also has strong acid resistance and reusability,and also maintains high adsorption in environmental water samples.Alg-Mel adsorbent has the advantages of low raw material cost,simple synthesis process,high adsorption efficiency and recyclability,and has great potential in the treatment of lead-containing wastewater.2.Using sodium alginate and polyethyleneimine as raw materials,a green alginate-polyethyleneimine?Alg-PEI?composite gasification with a large adsorption capacity for Cu²⁺was successfully prepared by one-step synthesis.gum.The experimental results show that Alg-PEI has good adsorption to Cu²⁺,Zn²⁺,Co²⁺,Fe²⁺and Cr³⁺in wastewater,and it is selective for Cu²⁺.The selectivity coefficient is greater than 50 in the presence of various ions.The maximum adsorption capacity for Cu²⁺is as high as 241.4 mg/g,which exceeds the maximum adsorption capacity of most Cu²⁺adsorbents reported in the literature.In addition,Alg-PEI can be regenerated by simple acid washing,and the adsorption performance remains stable after 10 cycles.These characteristics indicate that the prepared Alg-PEI has broad application prospects in the treatment of Cu²⁺-containing wastewater.3.Using sodium alginate and polyethyleneimine as raw materials,a sodium alginate-polyamide-amine?Alg-PAMAM?composite aerogel adsorbent was prepared by one-step synthesis,and Alg-PAMAM has good adsorption to Pb²⁺,Cr³⁺,Ba²⁺,Cd²⁺,Co²⁺,Cu²⁺and Zn²⁺in wastewater.The adsorption rates for Pb²⁺,Cr³⁺,Ba²⁺and Cd²⁺are99.27%(Pb²⁺),98.68%(Cr³⁺),93.57%(Ba²⁺)and 86.68%(Cd²⁺),the maximum adsorption capacity for lead ions can reach 501.1mg/g.In the presence of a variety of ions,still maintain a high adsorption rate.It can be seen that the adsorbent has excellent adsorption capacity for various metal ions and has the ability to treat wastewater containing a plurality of heavy metal ions.