【作者】 高云霞；

【导师】 孙宝盛；

【作者基本信息】 天津大学 ， 环境工程， 2006， 硕士

【摘要】 离子选择电极是近30多来年,在电位分析法的领域内发展起来一个新兴而活跃的分支。由于其独特的特点,如简便、快速、所需测量仪器易于小型化、自动化、适合于现场分析、不破坏水样。已广泛应用于化工、环境、医药等科学研究中。为解决分析化学领域中某些难以解决的问题提供了有效手段。尽管如此,共存离子对测量的干扰,制约了离子选择电极分析方法的广泛应用。传统的解决方法是投加化学掩蔽剂来去除干扰,操作程序复杂、浪费化学试剂,而且有可能带来新的干扰,并且大多只限于单种离子的测定,测定效率偏低。本研究针对该法存在的上述问题,研究了用离子选择性电极法同时测定Cd²⁺、Pb²⁺,结合计算机MATLAB和EXCEL语言把化学计量学中的多元线性回归应用到离子选择性电极多组分同时测定中。考察了离子选择电极测定铜、镉、铅离子的最佳工作条件,重点是对测定影响较大的水样pH、总离子强度调节液、温度以及响应时间。研究表明测定铜、镉、铅时水样的pH应控制在5～5.5左右,总离子强度调节液均采用0.1mol/L的KNO₃,温度要保持恒定（控制在25～30℃）,响应时间不超过2分钟。检验了所建立回归方程的线性范围,在无干扰的情况下,三种离子的线性范围均为10-3～5×10^-7mol/L。配制了64种不同浓度等级铅、镉的混合溶液,分别测定了铅离子选择电极、镉离子选择电极对64种混合溶液的响应值,根据响应值和铅、镉的浓度,采用多元线性回归结合MATLAB和EXCEL语言编制计算机程序,从而回归出两个线性回归方程。测定十个自配水样的电极电位值,通过所建立的回归方程,编制计算机程序计算出自配水样的镉、铅浓度,与已知浓度作比较,相对误差在10%之内,表明方法的准确度较好。同时采用此法又测定了某冶炼厂的实际工业废水中的镉、铅含量,与原子吸收分光光度法所测结果进行了比较,结果相差甚小,同时获得较高的精密度。更多还原

【Abstract】 The ion selective electrode is a new and active branch in the potentiometry field in recent thirty years.Because of its special advantage,such as easy,rapid,fitful to analyse on the spot and not ruin the water sample,it has been widely used in the study of chemistry sciences ,environment sciences and medical sciences,etc.The technology provides efficient method for resolving some difficult problems in analytical chemistry field.For all that,the interference in determination arose from accompanying ions has been restricting the wide use of ion selective electrode.Traditional method for resolving the problem is adding chemistry concealment.However,the procedure of operation is complex,wasteful and it may bring new interference,at the same time,the determination is limited to single ion,so its efficient of determination is pool.In face of above problems,the research adopts ion selective electrode to determine accompanying interactional ions of Cd²⁺ and Pb²⁺.Meanwhile,combing MATLAB and EXCEL language of computer the research determines two component by using the multiple linear regression analysis to ion-selectrode.The best work conditions determining Cu²⁺ Cd²⁺ Pb²⁺with ion-selectrode are studied.The emphasis is pH value,TISAB,temperature and response-time of water sample which are effect factors on ion-selectrode.The research shows determining Cu²⁺ Cd²⁺and Pb²⁺ pH value will be controlled about 5～5.5, TISAB will adopt 0.1mol/L KNO3,temperature will be kept constant（25～300C） and response-time is less than two minutes. The linear range of regression equations are tested.Without interference,three ions’linear range are 10-3～5×10^-7mol/L.Different concentration grades 64 mix solutions are compounded.and they are determined with Cd²⁺ ion-selectrode and Pb²⁺ ion-selectrode.According to response-values and concentration,two linear regression equations are built by using the multiple linear regression analysis to ion-selectrode combing MATLAB and EXCEL language of computer.Potentionmetric of ten water samples compounded by myself are determined.By regression equations and computer procedure , the concentration of five water samples are worked out.RE% is within 10%,meanwhile ,using the method determines Cd²⁺ and Pb²⁺ concentration of true industrial waste water from a factory,and the result is compared with one of Atomic Absorption Spectrophotometry.Disparity of the更多还原