【摘要】 研究了硫镍试金法应用于失效汽车催化剂中铂、钯、铑富集的方法,探讨了小型硫镍试金应用于前处理失效汽车催化剂类样品的试金配方,结合正交试验法和控制变量法考察了熔炼温度、熔炼时间、硅酸度、捕集剂镍粉量、硫镍质量比例、助熔剂用量和助熔剂配比对样品前处理效果的影响。最佳试金配方为:熔炼温度为1 050℃;熔炼时间为30 min;硅酸度K=3.5;0.88g镍;m(Ni)∶m(S)=0.9∶1;4g助熔剂(m(Na2CO3)∶m(Na2B4O7)=1∶2)。以硫镍试金-碲共沉淀-电感耦合等离子体原子发射光谱法(ICP-AES)测定失效汽车催化剂中的铂、钯、铑,方法中铂、钯、铑的检出限分别为0.008 9、0.005 1、0.002 4μg/mL。按照实验方法对样品RM-1、RM-2、RM-3(企业内部质控样)和标准样品GYBW-CHJ-1中铂、钯、铑进行测定,结果的相对标准偏差(n=6)在0.14%~2.7%之间,测定值均与参考值/认定值相吻合。更多还原

【Abstract】 The enrichment method of platinum,palladium and rhodium in spent auto-catalysts by sulfurnickel assaying method was studied.The formula of small-scale sulfur-nickel assaying for the pretreatment of spent auto-catalyst samples was discussed.The influence of smelting temperature,smelting time,silicon acidity,dosage of nickel powder trapping agent,the mass ratio of sulfur and nickel,the dosage and ratio of flux on the pretreatment of sample was investigated by orthogonal experiment and control variable methods.The optimal assaying formula was obtained:the smelting temperature was 1 050 ℃,the smelting time was 30 min,the silicon acidity was K=3.5,the dosage of nickel was 0.88 g,the mass ratio of sulfur and nickel was m(Ni)∶m(S)=0.9∶1,and the dosage of flux was 4g(m(Na2CO3)∶m(Na2B4O7)= 1∶2).The content of platinum,palladium and rhodium in spent auto-catalysts was determined by sulfur-nickel assaying-tellurium coprecipitation-inductively coupled plasma atomic emission spectrometry(ICP-AES).The detection limit of platinum,palladium and rhodium in this method was 0.008 9μg/mL,0.005 1μg/mL and0.002 4μg/mL,respectively.The platinum,palladium and rhodium in actual samples(RM-1,RM-2and RM-3;internal quality control samples in enterprise)and certified reference material(GYBW-CHJ-1)was determined according to the experimental method.The relative standard deviations(RSD,n=6)were between 0.14% and2.7%.The found results were consistent with the reference/certified values.更多还原