COPPER(Ⅱ)-SILK FIBROIN COMPLEX FIBER AS AIR-PURIFYING MATERIAL

摘要

To remove ammonia, traditional activated carbon is not as effective as expected. In this paper, a new alternative method of removing ammonia by metal-silk fibroin complex fiber through coordination displacement reaction was proposed and studied. Electron spin resonance spectra(ESR) and atomic absorption spectrometry showed that the Cu(O)_4complex with low copper(Ⅱ) content was formed when silk fibroin was soaked in cupric aqueous solution under acid condition, while the structure of Cu(N)_4 complex with high copper (Ⅱ) content was formed in alkalic cuprammonia solution. Experimental results further showed that Cu(O)_4 complex is more effective than Cu(N)_4 complex in term of ammonia adsorption. It is highly desirable to prepare a deodorizing material that has both high copper(Ⅱ) content and Cu(O)_4 complex structure. Based on the study, a novel deodorizing fiber was prepared as follows: Silk fibroin fiber was treated with tannic acid (TA) firstly, then it was dipped into cuprammonia solution to obtain Cu(O)_4 complex containing 8.5% (wt%) copper(Ⅱ). Such fiber showed high deodorizing performance and can be regenerated by heating.