本文選題：氟 + 測(cè)定��； 參考：《華北理工大學(xué)》2017年碩士論文

【摘要】：氟化鈣在連鑄保護(hù)渣中起著助熔劑的作用,可以降低連鑄保護(hù)渣的熔點(diǎn),有利于保護(hù)渣的熔化,并降低保護(hù)渣的粘度,從而改善液渣的流動(dòng)性。但在連鑄過程中保護(hù)渣氟化鈣中氟的逸出并進(jìn)入大氣,會(huì)對(duì)環(huán)境造成嚴(yán)重的污染。研究中采用電化學(xué)方法進(jìn)行連鑄保護(hù)渣中氟含量進(jìn)行測(cè)定。探討了測(cè)定溶液的條件和保護(hù)渣樣品的分解條件對(duì)氟測(cè)定的影響。以甘汞電極為參比電極,用氟離子選擇電極對(duì)電極電勢(shì)進(jìn)行氟的測(cè)定,氟離子測(cè)定時(shí)采用的總離子濃度緩沖溶液(TISAB)是:環(huán)己二胺四乙酸二鈉鹽(CDTA)-磷酸氫二鉀-磷酸二氫鉀(p H5.8),溫度為30℃,氟離子濃度在2×10~(-4)~4×10~(-3)mol/L范圍內(nèi),E和lgc F-呈現(xiàn)良好的線性相關(guān)性,線性方程為y=-62.493x-51.89,相關(guān)系數(shù)為R2=0.9978;實(shí)驗(yàn)了連鑄保護(hù)渣樣品分解的不同熔劑效果,確定了在0.1g保護(hù)渣樣品下,最佳熔劑及用量為:1.2g Na_2O_2+0.6g Zn O,最佳的熔樣溫度范圍為750℃~800℃;通過實(shí)驗(yàn)確定了采用熱水進(jìn)行熔渣浸取效果較好;通過標(biāo)準(zhǔn)加入法測(cè)定了在保護(hù)渣樣品中加入氟化鈉后氟的回收率,當(dāng)氟化鈉加入量在2%~8%范圍內(nèi)時(shí),氟的回收率在98.9%~103.3%范圍內(nèi),結(jié)果滿意。在上述最佳條件下,對(duì)4個(gè)氟含量在2.27%~7.23%的不同的保護(hù)渣樣品進(jìn)行了測(cè)定,平行樣測(cè)定值相符性較好,說明了該測(cè)定方法的可行性。
[Abstract]:Calcium fluoride acts as a flux in continuous casting mold flux, which can reduce the melting point of continuous casting mold powder, be beneficial to the melting of mold powder, and reduce the viscosity of mold slag, thus improving the fluidity of liquid slag. However, in the continuous casting process, the release of fluorine from the mold powder calcium fluoride and its entry into the atmosphere will cause serious pollution to the environment. The fluorine content in continuous casting mold powder was determined by electrochemical method. The influence of the conditions for the determination of fluorine and the decomposition condition of the mold powder sample on the determination of fluorine was discussed. The fluorine potential of the electrode was determined by fluorine ion selective electrode with calomel electrode as reference electrode. The total ion concentration buffer solution (TISAB) used in the determination of fluorine ion is: cyclohexanediamine tetraacetic acid disodium salt, CDTA-dipotassium phosphate, potassium dihydrogen phosphate, potassium dihydrogen phosphate, pH 5.8, the temperature is 30 鈩，

本文編號(hào)：1798932