本文關(guān)鍵詞： 鉻酸鹽 結(jié)晶 介穩(wěn)區(qū) 微量離子 ICP-OES　出處：《中國(guó)科學(xué)院研究生院(青海鹽湖研究所)》2016年博士論文　論文類型：學(xué)位論文

【摘要】：鉻酸鈉、重鉻酸鈉、鉻酸酐作為重要鉻酸鹽產(chǎn)品,在工業(yè)上有廣泛的用途,既可以直接用作氧化劑、鞣革劑、著色劑,同時(shí)也是合成其他鉻酸鹽產(chǎn)品的重要原料。受生產(chǎn)工藝限制,國(guó)內(nèi)絕大多數(shù)的鉻鹽產(chǎn)品品質(zhì)不如國(guó)外,高端鉻鹽產(chǎn)品的生產(chǎn)需要先進(jìn)的生產(chǎn)工藝。清潔環(huán)保的電合成鉻酸鹽工藝是獲取高品質(zhì)鉻酸鹽產(chǎn)品的首選工藝技術(shù),而相應(yīng)鉻酸鹽結(jié)晶動(dòng)力學(xué)數(shù)據(jù)是獲取高品質(zhì)鉻鹽產(chǎn)品的基礎(chǔ);目前,國(guó)內(nèi)外鮮有鉻酸鈉、重鉻酸鈉、鉻酸酐等鉻鹽結(jié)晶學(xué)相關(guān)研究工作的報(bào)道、缺乏高純度鉻鹽雜質(zhì)組成的定量檢測(cè)標(biāo)準(zhǔn)。針對(duì)這些問(wèn)題,本文采用激光濁度法研究了鉻酸鹽體系結(jié)晶熱力學(xué)、結(jié)晶動(dòng)力學(xué)、成核動(dòng)力學(xué)等結(jié)晶學(xué)性質(zhì),使用電感耦合等離子體發(fā)射光譜法(ICP-OES)檢測(cè)鉻酸鹽產(chǎn)品中微量元素,并進(jìn)行了工業(yè)鉻酸鈉、工業(yè)重鉻酸鈉、工業(yè)鉻酸酐產(chǎn)品微量雜質(zhì)離子定量檢測(cè)方法的標(biāo)準(zhǔn)化工作,主要研究?jī)?nèi)容包括以下幾方面:1.采用動(dòng)態(tài)變溫法研究了293K~323K(20℃~50℃)Na2CrO4·4H2O-H2O體系、Na2Cr2O7·2H2O-H2O體系、Na2CrO4-Na2Cr2O7·2H2O-H2O體系、H2CrO4-Na2Cr2O7·2H2O-H2O體系中鉻酸鈉、重鉻酸鈉的溶解度性質(zhì),并通過(guò)范德霍夫方程研究了鉻酸鈉以及重鉻酸鈉在相應(yīng)體系中的溶解結(jié)晶熵變和焓變。2.通過(guò)激光濁度法研究了293K~323K(20℃~50℃)Na2CrO4·4H2O-H2O體系、Na2Cr2O7·2H2O-H2O體系、Na2CrO4-Na2Cr2O7·2H2O-H2O體系、H2CrO4-Na2Cr2O7·2H2O-H2O體系中鉻酸鈉、重鉻酸鈉的介穩(wěn)區(qū)性質(zhì),并考察了降溫速率、飽和溫度、轉(zhuǎn)速、晶種以及鉻酸鈉、鉻酸的加入對(duì)介穩(wěn)區(qū)寬度的影響。3.使用經(jīng)典成核理論研究了鉻酸鈉、重鉻酸鈉在相關(guān)體系的成核動(dòng)力學(xué)方程以及成核級(jí)數(shù)m;通過(guò)自洽方程理論研究了鉻酸鈉、重鉻酸鈉在相關(guān)體系的成核常數(shù)K和成核級(jí)數(shù)m,并根據(jù)K的變化解釋了相關(guān)體系介穩(wěn)區(qū)變化的規(guī)律;采用三維成核理論研究了鉻酸鈉、重鉻酸鈉在相關(guān)體系的成核參數(shù)A和固液界面能γ,根據(jù)固液界面能在相關(guān)體系中的變化解釋了相應(yīng)體系介穩(wěn)區(qū)變化的規(guī)律。4.采用電感耦合等離子體發(fā)射光譜法(ICP-OES)對(duì)鉻酸鹽產(chǎn)品中微量雜質(zhì)離子進(jìn)行了定量分析,由于鉻酸鹽產(chǎn)品本身氧化性較強(qiáng),基體較為復(fù)雜,為盡可能消除基體本身對(duì)元素測(cè)定的干擾,選擇適合于鉻酸鹽體系的檢測(cè)方法,首先以鉻酸鈉為例嘗試了直接標(biāo)準(zhǔn)曲線法、基體匹配標(biāo)準(zhǔn)曲線法、標(biāo)準(zhǔn)加入法、氯化鋇除鉻法對(duì)其微量雜質(zhì)離子進(jìn)行了檢測(cè),通過(guò)對(duì)檢出限、精密度、回收率的等分析指標(biāo)的考察最終選擇出兩種適合于鉻酸鹽的檢測(cè)方法:基體匹配標(biāo)準(zhǔn)曲線法和標(biāo)準(zhǔn)加入法。將這兩種方法應(yīng)用于三種鉻酸鹽產(chǎn)品的檢測(cè),并進(jìn)行相應(yīng)的標(biāo)準(zhǔn)化工作,在此基礎(chǔ)上分別建立了工業(yè)鉻酸鈉、工業(yè)重鉻酸鈉、工業(yè)鉻酸酐中微量離子檢測(cè)的地方標(biāo)準(zhǔn)。
[Abstract]:As an important chromate product, sodium chromate, sodium dichromate and chromic anhydride are widely used in industry, which can be used as oxidant, tanning agent and colorant. At the same time, it is also an important raw material for the synthesis of other chromate products. Due to the limitation of the production process, the quality of the vast majority of chromate products in China is inferior to that in foreign countries. Advanced production technology is needed for the production of high-end chromate products. Clean and environmentally friendly electrosynthesis chromate process is the first choice to obtain high quality chromate products. The corresponding chromate crystallization kinetics data is the basis of obtaining high quality chromate products. At present, there are few reports on Crystallization of chromate, such as sodium chromate, sodium dichromate, chromic anhydride and so on. In this paper, the crystallization thermodynamics, crystallization kinetics and nucleation kinetics of chromate system have been studied by using laser turbidimetric method. Inductively coupled plasma emission spectrometry (ICP-OES) was used to detect trace elements in chromate products and industrial sodium chromate and sodium dichromate were carried out. Standardization of quantitative determination of trace impurity ions in industrial chromic anhydride. The main research contents are as follows: 1. The system of 293K ~ (3 +) ~ (32) K ~ (2 +) C ~ (20 鈩，

本文編號(hào)：1457950