原子吸收光谱法测定茂金属催化剂中的微量金属

Determination of trace metals in metallocene catalysts by atomic absorption spectrometry

关键词:  茂金属催化剂  原子吸收光谱法  化学干扰  释放剂  湿法消解

Key words:  metallocene catalyst  atomic absorption spectrometry  chemical interference  releasing agent  wet digestion

摘要:

茂金属催化剂的成分较为复杂,考察了各主量元素对K、Ca、Na、Mg的影响。结果 表明,Al和Ti对各测定元素存在较为严重的化学干扰。采用加入释放剂La和Sr共同消除干扰,并考察了释放剂的种类和用量。采用湿法消解制备茂金属催化剂样品,原子吸收光谱法测定催化剂中的K、Ca、Na、Mg。各元素的校准曲线相关系数大于0.999,检出限小于0.03 μg/mL。同时对样品进行了精密度和准确度考察,结果的相对标准偏差小于2%,回收率为95%～104%。 

Abstract:

The composition of metallocene catalyst was complex. The effects of major elements on potassium, calcium, sodium and magnesium were investigated. The result showed that aluminum and titanium had more serious chemical interference on the determination elements, and the interference was eliminated by adding release agents La and Sr. The types and amount of release agent were also investigated. The samples of metallocene catalyst were prepared by wet digestion, and the potassium, calcium, sodium and magnesium in the catalyst were determined by atomic absorption spectrometry. The calibration curve correlation coefficient of each element is greater than 0.999, and the detection limit is less than 0.03 μg/mL. The precision and accuracy of the sample were also investigated. The relative standard deviation of the result was less than 2%, and the recovery rate was 95%-104% within determining concentration scope of each element.