酸值試驗儀(yi)的試驗步驟∶

1、驅(qu)除二氧化碳(tan)取95%的(de)乙(yi)醇50毫升注入清潔無水的(de)錐形燒瓶(ping)內，用裝(zhuang)有回(hui)流(liu)冷(leng)凝管的(de)軟木塞塞住錐形燒瓶(ping)后，將95%的(de)乙(yi)醇煮沸5分鐘。

2、中和抽提溶(rong)劑(ji)﹐在煮沸過(guo)的(de)(de)95%的(de)(de)乙醇(chun)中加入0.5毫(hao)升的(de)(de)堿性藍溶(rong)液(ye)（或酚酞溶(rong)液(ye))后，在不斷搖蕩下趁熱用0.05M的(de)(de)氫氧(yang)化鉀乙醇(chun)溶(rong)液(ye)滴定，直至錐形瓶中混合(he)物(wu)的(de)(de)顏色由藍色變為(wei)淺紅(hong)色或滴至淺玫(mei)瑰(gui)紅(hong)色為(wei)止。

3、取(qu)樣―汽油或煤(mei)油取(qu)50 mL，柴油取(qu)20 mL(均在20℃±3℃溫度范圍內量取(qu))將試樣注入中(zhong)和過的熱的95%乙醇中(zhong)。

4、滴(di)定(ding)操(cao)作(zuo)將(jiang)球形(xing)(xing)回流冷(leng)凝管裝到錐(zhui)形(xing)(xing)瓶上(shang)之后，將(jiang)錐(zhui)形(xing)(xing)瓶中的(de)混(hun)合物煮沸5 min，對(dui)已加(jia)有堿性(xing)藍(lan)6B溶(rong)(rong)(rong)(rong)液(ye)(ye)或(huo)甲酚(fen)(fen)紅(hong)(hong)溶(rong)(rong)(rong)(rong)液(ye)(ye)的(de)混(hun)合物，此時(shi)應再加(jia)入(ru)0.5 mL的(de)堿性(xing)藍(lan)6B溶(rong)(rong)(rong)(rong)液(ye)(ye)或(huo)甲酚(fen)(fen)紅(hong)(hong)溶(rong)(rong)(rong)(rong)液(ye)(ye)，仍需(xu)在不斷搖蕩下(xia)趁熱用0.05 mol / L氫氧化鉀乙醇(chun)溶(rong)(rong)(rong)(rong)液(ye)(ye)滴(di)定(ding)，直(zhi)至(zhi)95%乙醇(chun)層的(de)堿性(xing)藍(lan)6B溶(rong)(rong)(rong)(rong)液(ye)(ye)從藍(lan)色(se)變為(wei)(wei)淺紅(hong)(hong)色(se)(甲酚(fen)(fen)紅(hong)(hong)溶(rong)(rong)(rong)(rong)液(ye)(ye)從黃(huang)色(se)變為(wei)(wei)紫(zi)紅(hong)(hong)色(se))為(wei)(wei)止;或(huo)對(dui)已加(jia)有酚(fen)(fen)酞(tai)(tai)溶(rong)(rong)(rong)(rong)液(ye)(ye)的(de)混(hun)合物，此時(shi)應再加(jia)入(ru)1~②滴(di)酚(fen)(fen)酞(tai)(tai)溶(rong)(rong)(rong)(rong)液(ye)(ye)，按上(shang)述(shu)操(cao)作(zuo)直(zhi)至(zhi)95%乙醇(chun)層的(de)酚(fen)(fen)酞(tai)(tai)溶(rong)(rong)(rong)(rong)液(ye)(ye)呈(cheng)現淺玫瑰(gui)紅(hong)(hong)色(se)為(wei)(wei)止。