摘要
随着环保要求的日益严格,TMT-15在燃煤电厂脱硫废水处理工程中应用越来越广泛。本文利用共轭酸碱和共轭均三嗪环等特点,研究了TMT-15的有效物Na_3TMT含量和水中残余TMT含量的测定原理、介质条件、测定步骤以及测定方法的准确度和精密度。结果表明:根据H_3TMT的3级离解常数,用H_2SO_4做滴定剂,在自动电位滴定仪上分别设定pH=9.87和pH=3.62为酸碱滴定的起点和终点,可以测定TMT-15中有效物Na_3TMT含量;由于Na_3TMT分子中的共轭均三嗪环在l=300 nm处有强紫外吸收(e=10^(4.03) L/(mol·cm)),采用紫外可见分光光度计和1 cm石英比色皿,在1 mol/L NaOH介质中,绘制Na_3TMT溶液的质量浓度(单位mg/L)与吸光度标准曲线,数据的线性相关性较好,可用于测定水体中残余的TMT含量。此研究结果解决了TMT含量的测定问题,有助于合理准确地验收、投加和评估TMT-15药剂。
With the increasingly strict environmental protection requirements,TMT-15 is more and more widely used in desulfurization wastewater treatment projects of coal-fired power plants.Based on the characteristics of conjugated acid base and conjugated triazine ring,the determination principle,medium conditions,detection procedure and the accuracy and precision of the method for determining the effective substance Na3TMT content of TMT-15 and the residual TMT content in water were studied.The result indicates that,according to the acid dissociation constants Ka1,Ka2 and Ka3 of H3TMT,using H2SO4 as the titrant and setting the pH value of 9.87 and 3.62 as the starting point and the end point of the acid-base titration on the automatic potentiometric titrator,the content of Na3TMT in the TMT-15 can be determined.Because the conjugated homotriazine ring in Na3TMT molecule has strong ultraviolet absorption atλ=300 nm(ε=10^4.03 L/(molcm)),the standard curve of Na3TMT solution mass concentration(mg/L)against absorbance plotted by using UV-Vis spectrophotometer and 1 cm quartz colorimetric dish in 1 mol/L NaOH solution has good linear correlation,which can be used to determine the residual TMT content in water.The paper gave the method for determining the TMT concentration in aqueous solutions and effluents,helping to accurately accept,add,and evaluate TMT-15 agents.
作者
廖冬梅
王正江
LIAO Dongmei;WANG Zhengjiang(College of Power & Mechanical Engineering,Wuhan University,Wuhan 430072,China;Xi’an Thermal Power Research Institute Co.,Ltd.,Xi’an 710054,China)
出处
《热力发电》
CAS
北大核心
2019年第1期115-120,共6页
Thermal Power Generation
关键词
TMT
离子分率
酸碱电位滴定
紫外吸收光谱
紫外可见分光光度法
TMT
ionic fraction
acid-base potentiometric titration
UV absorption spectrum
ultraviolet spectrophotometry
