Study On Enrichment Of Cd, Fe, Ni, Zn In Seawater Using Functional Fiber And Determination By ICP-AES

In this paper, the current situation and progress of separation and enrichment of Cd, Fe, Ni, Zn in seawater at home and abroad were reviewed. Based on the characteristic of functional group of ion exchange fiber can adsorb some metal ion selectively under certain conditions, enrichment of trace Cd, Fe, Ni, Zn in seawater using the strong acid cation exchange fiber, strong alkaline anoin exchange fiber, PAN-S loaded fiber before its determination by ICP-AES were investigated.1. The conditions of concentration and elution of trace Cd, Fe, Ni, Zn in seawater using the strong acid cation exchange fiber were optimized. The results showed that when the pH=1.5 and volume of seawater sample was within 1000mL, Cd, Fe, Ni, Zn were successfully enriched at the flow rate within 8mL/min. Then it were eluted from the column quantitatively by 10mL 1.8mol/L HNO3. The contents of coexisting ions in eluent were:Ca2+(1.92mg), K+(0.091mg), Mg2+(15.3mg), Na+(0.325mg), Ba2+(16.7μg), Cu2+(0.324μg), Pb2+(0.055μg), Mn2+(0.237μg), Al3+(0.677μg), it had no effect on the determination. The detection limit were Cd 0.011μg·L-1, Fe 0.069μg·L-1, Ni 0.037μg·L-1, Zn 0.006μg·L-1.The recovery was between 94.4%～101% and the relative standard deviation (RSD) was between 0.5%～6.1%. The method was validated by the determination of the standard material GBW(E)080040 and NASS-6.2. A method of 8-hydroxyquinoline chelated-strong alkaline anion exchange fiber enrichment of trace Cd, Fe, Ni, Zn in seawater was studied. The condition of the method were optimized. The results showed that when the volume of seawater sample within 500mL, pH=5, Cd, Fe, Ni, Zn were chelated by 8-hydroxyquinoline and successfully enriched at the flow rate within 6mL/min, then it were eluted from the column quantitatively by 10mL 1.0mol/L HNO3. The contents of coexisting ions in eluent were:Ca2+(0.032mg), K+(0.045mg), Mg2+(0.039mg), Na+(0.107mg), Ba2+(17.1μg), Cu2+(0.357μg), Pb2+(0.05μug), Mn2+(0.23μg), Al3+(0.596μg), it had no effect on the determination. The detection limit were Cd 0.010μgL-1, Fe 0.079μg·L-1, Ni 0.040μg·L-1, Zn 0.006μg·L-1.The recovery was in the range of 96.0%～102% and the relative standard deviation (RSD) was in the range of 1.0%～4.8%. The method was validated by the determination of the standard material GBW(E)080040 and NASS-6.3. The conditions of enrichment and elution of trace Cd, Fe, Ni, Zn in seawater using PAN-S loaded fiber were optimized. The results showed that when the volume of seawater sample within 1000mL, pH=5, Cd, Fe, Ni, Zn were enriched at the flow rate within 6mL/min, then it were eluted from the column completely by 10mL 0.1mol/L HNO3. The contents of coexisting ions in eluent were:Ca2+(0.029mg), K+(0.023mg), Mg2+(0.030mg), Na+(0.086mg), Ba2+(15.4μg), Cu2+(0.328μg), Pb2+(0.044μg), Mn2+(0.229μg), Al3+(0.608μg), it had no effect on the determination. The detection limit were Cd 0.010μg·L-1, Fe 0.056μg·L-1, Ni 0.037μg·L-1,Zn 0.005μg·L-1.The recovery was between 93.1%～100% and the relative standard deviation (RSD) was between 0.5%～ 4.7%. The method was validated by the determination of the standard material GBW(E)080040 and NASS-6.