Improvement Of Stripping Voltammetry For Determination Of Heavy Metals By Using Co-deposition Ions

The heavy metals such as Pb,Hg,Zn,Cu,Cd are severely endangering human health due to their toxicity,enrichment, non-biodegradability through drinking water,bioaccumulation and food chain etc.Therefore,quick and accurate determination of heavy metals is of great significance.Electrochemical method has a lot of advantages such as the fast detection speed,the simplicity,the small instrument,the low cost and can be used on the spot.Thus,it has played a great role in detection of heavy metals,and it has great development prospect.The purpose of this thesis is to study on quick and efficient detection of heavy metals in food or water with the non-mercury and non-toxic stripping voltammetry to enhance the sensitivity based on co-depositon ions,and develop heavy metal scene fast detector.The major contents of this thesis are as followed:(1)The antimony film modified glassy carbon electrode(GCE) was prepared by in-situ plating for determination of trace lead and cadmium by square wave stripping voltammetry(SWSV).The optimized conditions to detect Pb2+and Cd2+simultaneously were discussed.The present method was applied to the determination of cadmium in rice samples,and the relative standard deviation (RSD) was in the range of2.6～3.5%. The results were compared with ICP-AES method,which indicated the method was reliable.The proposed method can have practical utility.(2)A novel method for the detection of Hg(Ⅱ) with the presence of copper(Ⅱ) by stripping voltammetry is developed.It indicated that copper(Ⅱ) can enhance the sensitivity of determination of Hg(Ⅱ) without Sb(Ⅲ).A series of experiments have been carried out to obtain optimized parameters.Under the optimized conditions,the linear range of Hg(Ⅱ) is10-100μg/L,and the detection limit is10μg/L(3)A series of research have been carried out,which focused on electrochemical method for determination of arsenic,antimony,lead,zinc and setting parameters.The optimal experimental conditions have been integrated into the heavy metal scene fast detector.And the fast digestion method on the scene has been explored.Finally,the field rapid digestion device was successfully developed.