魏增 柯艷 張彥斌 馮亞梅 馬熠罡



摘? ? ? 要: 針對測定偏釩酸銨中雜質元素實驗方法準確性的問題,為進一步分析實驗測定過程的影響因素及測定結果的可靠性,將偏釩酸銨樣品利用熱水和氨水溶解,選擇電感耦合等離子體光譜法測定偏釩酸銨中16種雜質元素,實驗測定過程嚴格按照等離子體光譜法操作流程。實驗中選擇了利用熱水和氨水的溶解的方式、并分析了測定元素的波長,并進行了背景校正。分析了偏釩酸銨樣品中雜質元素含量,選擇靈敏度滿足要求的譜線。利用基體匹配和同步背景校正,有效的去除了光譜干擾。實驗結果表明,各元素檢出限在0.000 1%~0.001 8%之間,RSD在0.40%~8.9%之間,加標回收率介于92.0%~107%之間,實驗表明了電感耦合等離子體光譜法可以滿足偏釩酸銨中雜質元素測定的要求,具有一定的技術優勢。
關? 鍵? 詞:化學分析;元素測試;偏釩酸銨;電感耦合等離子體光譜法
中圖分類號:TQ 113.79; O657.31? ? ?文獻標識碼: A? ?文章編號: 1671-0460(2019)09-2121-04
Abstract:? Aiming at the accuracy of the experimental method for determination of impurity elements in ammonium metavanadate, in order to further analyze the influencing factors of the experimental process and the reliability of the results, the sample of ammonium metavanadate was dissolved in hot water and ammonia water, and 16 impurity elements in ammonium metavanadate were determined by inductively coupled plasma spectrometry. In the experiment, the dissolving method of hot water and ammonia water was chosen, and the wavelength of the determined elements was analyzed, and the background correction was carried out. The content of impurity elements in ammonium metavanadate samples was analyzed, and the spectral lines with satisfactory sensitivity were selected. Matrix matching and synchronous background correction were used to remove spectral interference effectively. The experimental results showed that the detection limit of each element was between 0.0001% and 0.0018%, RSD was between 0.40% and 8.9%, and the recovery of standard addition was between 92.0% and 107%. The experimental results show that the inductively coupled plasma spectrometry can meet the requirements of impurity element determination in ammonium metavanadate and has certain technical advantages.
Key words: Chemical analysis; Element testing; Ammonium metavanadate; Inductively coupled plasma spectrometry
偏釩酸銨為白色或略帶淡黃色結晶粉末,作為提煉釩的重要物質,通過提煉加工后獲得五氧化二釩,最終通過一系列的冶煉過程得到金屬釩、釩鐵合金和其它釩基合金。同時偏釩酸銨也作為應用普遍的化學試劑、催化劑等,廣泛的應用在諸多化工領域[1]。目前,測定偏釩酸銨中雜質元素的方法主要有電感耦合等離子體法和分光光度法[2-4]。其中電感耦合等離子體原子發射光譜法是目前較為流行的光譜法測定元素的方法之一,相比其他方法而言,具有檢測極限小、對檢測元素的反應靈敏度高、基體效應小、檢測精準度較高、能實現多元素協同檢測和動態線性范圍較寬等特點,在測定偏釩酸銨中的雜質方面有顯著的優勢。但改檢測方法也有一定的弊端,即當測試樣品中含量較低的元素時,由于檢測干擾因素較多,使得檢測過程需要考慮樣品中含量較高的元素對檢測結果的光譜干擾影響,目前通過檢測實驗分析可知,這種高含量元素造成的干擾,極大概率地造成低含量元素的測試結果產生較大的偏差[5,6]。
本文基于電感耦合等離子體原子發射光譜法,探尋了利用該方法對偏釩酸銨中雜質離子的測定實驗過程,以及需和消除其它元素的光譜干擾。主要采用了波長分析、背景校正,并選擇了更為良好的相互結合測定方式,有效地避免了基體元素造成的干擾影響,實驗取得了較好的測試結果,驗證了電感耦合等離子體光譜法測定的技術優勢。