本文選題：硫鐵化合物 + 低溫氧化��； 參考：《鄭州大學》2015年碩士論文

【摘要】：本文對設備腐蝕樣品氧化固態(tài)中間產物的物相及表面特性和氣態(tài)產物釋放規(guī)律展開研究;結合均相沉淀樣品,對硫鐵化合物的氧化誘導期以及氧化動力學過程進行研究。通過低溫預氧化實驗,對設備腐蝕樣品的固態(tài)中間產物運用拉曼光譜分析和X射線衍射分析表明,預氧化前設備腐蝕樣品多以非晶態(tài)硫化亞鐵的形式存在,預氧化后樣品呈現為一個多相體系;采用BET法對其表面特性分析得出,隨著預氧化時間的延長,產物比表面積減小,孔隙率隨之減小。運用熱重-傅里葉轉換紅外光譜聯(lián)用手段研究設備腐蝕樣品氧化熱解過程及氣體釋放規(guī)律進行研究。結果表明,氧化熱解氣態(tài)產物包括SO2、SO3和少量的水,當溫度達到715℃時SO2析出量達到最大值;熱解殘余產物分析表明,S8不適于在硫鐵化合物氧化反應中作為定量分析的指標性產物。通過氧化誘導期實驗對設備腐蝕樣品和均相沉淀樣品的熱穩(wěn)定性及影響因素的研究表明,兩種樣品在125~200℃內處于活躍的自熱階段,熱穩(wěn)定性較差;對于超微粒徑和大顆粒的樣品均不利于硫鐵化合物的氧化反應,粒徑范圍44~74μm的樣品氧化誘導時間最短,自燃傾向性越高;升溫速率導致樣品的比表面積降低同時增強了樣品的氣體脫附能;空氣流速對誘導期的影響較小。采用熱重-差示熱掃描聯(lián)用分析了設備腐蝕樣品和均相沉淀樣品在多重升溫速率下的氧化熱解過程,運用Friedman,Starink和Kissinger三種非模型動力學方法計算得出了兩種樣品在各氧化階段的表觀活化能。分析表明,硫鐵化合物在151.4~417℃內逐步進行物相轉化,450.5~533.5℃內開始Fe S2的氧化熱解,668.8~840.7℃內硫酸鹽(或亞硫酸鹽)分步分解,熱解失重達到最大值;熱解失重階段均有SO2的析出,在低溫階段,SO2主要由物相轉化時析出的單質硫氧化生成,而高溫段硫酸鹽的分步熱解是SO2生成的主要原因。
[Abstract]:In this paper, the phase and surface characteristics of solid intermediate products and the release law of gaseous products were studied, and the oxidation induction period and oxidation kinetics of ferric sulfide compounds were studied in combination with homogeneous precipitated samples. By means of low temperature preoxidation experiments, Raman spectroscopy and X-ray diffraction analysis of the solid intermediate products of the equipment corrosion samples show that the corrosion samples are mostly in the form of amorphous ferrous sulfide before preoxidation. The surface properties of the samples were analyzed by BET method. The results show that the specific surface area decreases and the porosity decreases with the increase of preoxidation time. The oxidation pyrolysis process and gas release of corrosion samples were studied by thermogravimetric Fourier transform infrared spectroscopy (TFTIR). The results show that the oxidation pyrolysis gaseous products include so _ 2 so _ 3 and a little water, and the SO2 precipitation reaches the maximum value when the temperature reaches 715 鈩，

本文編號：1800638