Automatic Analysis Instrument Measured Cobalt Method

The determination of cobalt is very necessary in guiding and controlling the manufacture in the process of extraction. In order to determine the cobalt fast and accurately, an intelligent instrument was developed which needed the knowledge of chemistry, machine and electric circuit. The spectrophotomctric method and the flow injection analysis were combined to develop the instrument.The intelligent instrument for cobalt works on the base of the chemical method of nitroso-R-salt. Some experiments were carried out by the method of flow injection analysis and the influence of chromogenic agent's concentration, the inside diameter of pipe, the length of pipe, the flow rate of carrier, the analysis rate, the sampling volume and the shape of pipe on the absorption were discussed. It is found that the best work conditions for the instrument is as following: The chromogenic agent's concentration is 0.01%, the inside diameter of pipe is 0.5mm, the length of pipe is 100cm, the sampling volume is 150ul, the pipe is knotted. Under these optimal conditions, the linear range of 0.05 ~ 0.15 g/ L is obtained.The methods of the determination of highly concentrated sample were investigated. The highly concentrated sample can be determined on the instrument without changing the hard ware and the soft ware by the directly spectrophotometric method and the method of on-line dilution. The linear range of the directly spectrophotometric method is 0.5 -4.0g/L. The method of on-line dilution can be taken to determine the highly concentrated sample. It is found that when the sampling volume was reduced to 50ul , the mixer was added and the flow rate was increased, the linear range is between 0.5~2.0g/L.