Optimization of Nitric Acid Pretreatment Refractory Gold Concentrate Process with Multiple Assessment Indicators by Grey Relational Analysis

On one hand, refractory gold concentrate with high arsenic is one kind of pollutants; on the other hand, it contains a lot of valuable metals, so it is very important to utilize it. This paper studies the optimization of the nitric acid pretreatment refractory gold concentrate process with multiple assessment indicators by the grey relational analysis method. The degree of influence that the controllable process factors (reaction temperature, reaction time, initial nitric acid concentration and initial refractory gold concentrate concentration) exert on the indicators can be concluded as follows: initial refractory gold concentrate concentration > initial nitric acid concentration > reaction temperature > reaction time. The best factor combination is as follows: reaction temperature is 45degC; reaction time is 2.5 h; initial nitric acid concentration is 45%; initial gold concentrate concentration is 10%.