Study On The Synthesis Of Surful- And Nitrogen-Containing Chitosan Derivatives And Their Adsorption Properties For Metal Ions

â… . This paper generally stated the advance, physical-chemistry properties, structure and relevant chemical reaction of chitin/chitosan; reviewed the progress in studies on coordination chemistry between chitosan and their derivatives with metal ions; summarized the research of wastewater treatment by chitosan and their derivatives; discussed the studies on the adsorption properties of thiourea and its derivatives for noble metal ions; especially introduced the properties and application of phenylthiourea which was used in the experience of this paper. The advance of Crow ethers, especially mesocyclic diamines and their adsorption properties were also reviewed.â…¡. Four novel chitosan derivatives—phenylthiourea grafted N-benzylidene chitosan (â…£), phenylthiourea grafted chitosan (â…¤) , Dihydroxyl Mesocyclic Diamine grafted N-benzylidene chitosan (â…¥) and Dihydroxyl Mesocyclic Diamine grafted chitosan (â…§) were synthesized from chitosan.1. N-benzylidene chitosan(â… ) was prepared from the reaction between benzaldehyde and chitosan;, the intermediate product(â…¡) was formed by N-benzylidene chitosan(â… ) with epichlorodydrin under acidic condition ; under alkaline condition intermediate product(â…¡) turned to epoxy-activated product(â…¢), then reacted with phenylthiourea to form phenylthiourea grafted N-benzylidene chitosan (â…£); finally obtained phenylthiourea grafted chitosan (â…¤) after removing benzaldehyde.2. Epoxy-activated product(â…¢) reacted with Dihydroxyl Mesocyclic Diamine to form compound â…¥, finally obtained compound â…¦ after removing benzaldehyde.â…¢. The main intermediate products and target products were confirmed by elemental analysis,FT-IR spectra analysis, X-ray diffraction analysis and ¹³C NMR analysis . The result showed that all these compounds were expected.â…£. The adsorption properties of compounds â…¤ for metal ions (Cr⁶⁺, Cu²⁺) compared withchitosan were studied. On the same circumstances, we found that compound â…¤ have more Adsorption capacity and faster Metal uptake kinetics for metal Cr⁶⁺ than CTS ,while the Adsorption capacity for Cu²⁺ close to CTS. Compound â…¦ showed better adsorption selectivity for metal Ag⁺-Pb²⁺-Cr³⁺ than CTS.