【摘要】：社會(huì)的發(fā)展與進(jìn)步必然會(huì)導(dǎo)致人們對(duì)于環(huán)境、食品中安全意識(shí)的不斷增強(qiáng),因此也會(huì)不斷催生出越來越多的檢測(cè)方法和檢測(cè)儀器。在實(shí)際分析檢測(cè)過程中會(huì)碰到各種各樣的現(xiàn)實(shí)問題與尷尬境地亟待我們解決：比如火焰原子吸收法的操作方便、儀器價(jià)格便宜、靈敏度高,但是檢測(cè)限不夠低,達(dá)不到要求；再比如電感耦合等離子體發(fā)射光譜法的靈敏度高、檢測(cè)限可以達(dá)到ppb級(jí)別,但是儀器價(jià)格高昂,普通實(shí)驗(yàn)室或檢測(cè)機(jī)構(gòu)根本無力承擔(dān)。那么既可以使用成本低、操作快捷的火焰原子吸收法又可以使檢測(cè)方法的檢出限降低成為我們的研究目標(biāo)。共沉淀方法是應(yīng)用范圍較廣的一種分離富集預(yù)處理方法,它簡(jiǎn)單、快速而且富集倍數(shù)高,與火焰原子吸收法聯(lián)用可以檢測(cè)痕量的重金屬。本論文創(chuàng)新性地將以Bi(Ⅲ)、Al(Ⅲ)、Ba(Ⅱ)作為載體離子,以常見、便宜易得的1-(2-吡啶偶氮)-2-萘酚(PAN)作為共沉淀劑,共沉淀分離富集食物(如市售皮蛋、生花生及果醬)中的鉛、鎘、鉻和廢棄物(如廢舊無汞堿性電池)中的銦,并采用火焰原子吸收法對(duì)上述四種痕量重金屬的含量進(jìn)行測(cè)定。通過討論共沉淀劑1g/L PAN的加入量、一定濃度載體離子Bi3+、Al3+、Ba2+的加入體積、溶液pH值、共沉淀時(shí)間、樣品體積等因素選擇最優(yōu)共沉淀體系,通過分析共存離子的干擾、靈敏度、精密度、檢出限等論證了方法的優(yōu)越性。本論文還對(duì)相應(yīng)的共沉淀機(jī)理類型進(jìn)行了研究,不僅有利于對(duì)分析分離的理解而且可能對(duì)其它方面的研究有一定的指導(dǎo)意義。本文研究了如下四個(gè)體系來分離富集特定的痕量重金屬：一、Bi(Ⅲ)-PAN共沉淀體系檢測(cè)皮蛋樣品中的Pb。該方法的靈敏度為0.0143(mg/L)-1,精密度為1.31%,對(duì)鉛的檢出限為16.3μg/L。按正常程序進(jìn)行共沉淀(以下均稱先加)和先形成Bi(Ⅲ)-PAN再加入含鉛樣品(以下均稱后加),以上二者共沉淀形式均為表面吸附共沉淀。二、Bi(Ⅲ)-PAN共沉淀體系檢測(cè)生花生中的Cd。該方法靈敏度為0.1528(mg/L)-1,檢出限為3.40μg/L,精密度為0.16%。先加時(shí)Cd與Bi(Ⅲ)-PAN部分形成混晶與固溶體部分形成表面吸附,而后加時(shí)主要形成表面吸附。三、Al(Ⅲ)-PAN共沉淀體系檢測(cè)果醬中的Cr(總)。靈敏度為0.0461(mg/L)-1,檢出限為8.98 μg/L。先加和后加含鉻(總)試樣時(shí),Al(Ⅲ)-PAN與Cr的的共沉淀形式均為表面吸附。四、Ba(Ⅱ)-PAN共沉淀體系檢測(cè)廢舊電池中的In3+。該方法檢測(cè)痕量重金屬銦的靈敏度為0.0147(mg/L)-1,檢出限為20.4μg/L,方法精密度為0.79%。無論是先加樣品還是后加樣品Ba(Ⅱ)-PAN與痕量In3+的共沉淀形式均為表面吸附共沉淀類型。
[Abstract]:The development and progress of society will inevitably lead to the continuous enhancement of people's awareness of environment and safety in food. Therefore, more and more testing methods and instruments will be produced. In the process of practical analysis and detection, various practical problems and awkward situations need to be solved. For example, the operation of flame atomic absorption spectrometry is convenient, the instrument is cheap, the sensitivity is high, but the detection limit is not low enough to meet the requirements. For example, Inductively coupled Plasma Emission Spectrometry (ICP-AES) has high sensitivity, and the detection limit can reach the ppb level. However, the instrument is expensive and can not be borne by ordinary laboratories or testing institutions at all. Therefore, flame atomic absorption spectrometry (FAS), which can be used with low cost and fast operation, can reduce the detection limit of the detection method to become our research goal. Coprecipitation is a widely used pretreatment method for separation and preconcentration. It is simple, rapid and has high enrichment ratio. It can be used in combination with flame atomic absorption spectrometry for the determination of trace heavy metals. In this paper, Bi (鈪，

本文編號(hào)：2434075