摘要
目前靛酚蓝分光光度法的研究与应用多集中于氨浓度1μg/mL左右的测试,而实际生产活动中,涉及氨氮生产、氨氮固废处理的场所氨氮浓度较高,使用该方法测试时易存在检测误差。本文采用靛酚蓝分光光度法测定不同氨浓度溶液的氨氮吸光度,发现在0~100.00μg/mL的氨浓度范围内,吸光度先增加后降低:当氨浓度为0~1.00μg/mL时,氨含量与吸光度呈线型正相关;当氨浓度为0~3.00μg/mL时,氨含量与吸光度呈线型正相关,曲线斜率降低;当氨浓度为3.00~7.00μg/mL时,氨含量与吸光度仍呈正相关,但斜率进一步降低;当氨浓度为7.00~100.00μg/mL时,氨含量与吸光度呈负相关,且随着氨浓度的增加,氨反应量出现降低现象;进一步,发现100.00μg/mL高氨浓度时氨反应量甚至低于氨浓度为0.50μg/mL时。通过进行分析和试验研究,推测出上述反常现象原因:当氨浓度过高时,亚硝基铁氰化钠一方面会使反应转化率降低,另一方面,过量的氯胺可能会与亚硝基铁氰化钠的氰基发生化学反应,导致催化剂失活,进而影响催化反应活性。
The current research and application of Spectrophotometric IPB method is mainly focused on thedetection with an ammonia concentration of appr.1 g/mL,while in actual production activities,the ammonia nitrogen concentration in the places involving ammonia nitrogen production and solid waste treatment is relatively high,and errors may occur while using this method for detection.In this paper,the Spectrophotometric IPB method was used to detect the absorbance of ammonia nitrogen in the solutions with different ammonia concentrations,it was found that the absorbance increased first and then decreased in the concentration range of 0-100.00 g/mL;when the ammonia concentration was 0-1.00 g/mL,there was a linear positive correlation between the ammonia content and the absorbance;when the ammonia concentration was 0-3.00 g/mL,the ammonia content had a linear positive relationship with the absorbance,but the slope of the curve decreased;when the ammonia concentration was 3.00-7.00 g/mL,the ammonia content and the absorbance were positively correlated,but the slope further reduced;when the ammonia concentration was 7.00-100.00 g/mL,the ammonia content was negatively correlated with the absorbance,and with the increase of the concentration,the ammonia reacting dose lessened;furthermore,the reacting dose of ammonia at high ammonia concentration of 100.00 g/mL was even lower than that of 0.50 g/mL.Through analysis and experimental research,the reasons for such abnormal phenomenon were speculated that when the ammonia concentration was too high,the sodium nitroprusside would bring the reaction conversion rate down,and excess chloramines might react with the cyano group of the sodium nitroprusside,resulting in catalyst deactivation and weakening the activity of catalytic reaction.
作者
吴宁安
王瑞瑞
刘金利
房维洁
杜川
WU Ning-an;WANG Rui-rui;LIU Jin-li;FANG Wei-jie;DU Chuan(Tianjin Research Institute for Advanced Equipment,Tsinghua University,Tianjin 300304,China)
出处
《中国有色冶金》
CAS
北大核心
2022年第6期54-59,102,共7页
China Nonferrous Metallurgy
基金
国家重点研发计划课题“废树脂粉末协同干膜废料复合材料化技术”(2018YFC1902502)。
关键词
氨氮检测
高浓度氨氮
靛酚蓝分光光度法
氨浓度
吸光度
亚硝基铁氰化钠
催化反应
ammonia nitrogen detection
high-concentration ammonia nitrogen
spectrophotometric IPB method
ammonia concentration
absorbance
sodium nitroprusside
catalytic reaction
