摘要
处理后选矿废水中残余的聚丙烯酰胺(PAM)影响回水水质及其回用,本文为建立一种低检出限的低浓度PAM快速检测方法,在190~300 nm波长范围内建立了4种类型及分子量不同PAM的紫外吸收光谱,研究了不同浓度K^(+)和Ca^(2+)对PAM浓度检测的影响,并通过原子力显微镜(AFM)分析了PAM分子构象的变化.结果表明,4种类型的PAM峰值吸光度均在波长194 nm处测得,PAM浓度与吸光度之间具有强线性关系(R^(2)>0.98),检出限均低于0.1 mg·L^(-1),但PAM类型影响其浓度与吸光度的线性关系.随着K^(+)和Ca^(2+)浓度的增加,PAM溶液吸光度特征峰的强度逐渐降低并降速减缓,最大吸收波长不断红移,分别沉积在二氧化硅和金基底的APAM-3与CPAM-12的表面形貌粗糙度分别随K^(+)和Ca^(2+)浓度的增加而增大,说明PAM分子链在溶液中的构象逐渐变卷曲,使紫外光谱特征吸收峰的峰值降低,10、100 mmol·L^(-1) K^(+)与1、10 mmol·L^(-1) Ca^(2+)对PAM构象变化的影响程度基本相同.本研究实现聚丙烯酰胺的快速定量检测,对开展选矿水处理中聚丙烯酰胺的迁移规律研究具有重要意义.
The residual polyacrylamide(PAM)in treated mineral processing wastewater affects the quality of recycled water and its potential for reuse.Continuous circulation and accumulation of cations in mineral processing wastewater can also influence the chemical properties and flocculating performance of PAM.In this study,a rapid detection method for low detection limit and concentration of PAM was proposed.The ultraviolet absorption spectra of four types and different molecular weights of PAM were collected in the wavelength range of 190–300 nm.The sensitivity and detection limits of this ultraviolet spectral method of PAM were verified.The effects of different K^(+)and Ca^(2+)concentrations on the detection of PAM concentration were examined.Change in the PAM molecular conformation was analyzed using atomic force microscopy.The findings demonstrated that for the four polymers,the highest absorbance was recorded at 194 nm.There was a strong linear relationship between PAM concentration and absorbance(R^(2)>0.98).The limit of detection was lower than 0.1 mg·L^(-1).This method showed high detection sensitivity.However,the linear relationship between concentration and absorbance was affected by the type of PAM used.With increasing K^(+)and Ca^(2+)concentrations,the intensity of the absorbance characteristic peak of the PAM solution was reduced.The maximum absorption wavelength was continuously red-shifted.In addition,when the K^(+)and Ca^(2+)concentrations were greater than 50 and 5 mmol·L^(-1),respectively.The intensity of the characteristic absorbance peak gradually decreased.In deionized water,the surface roughness(Rq)values of APAM-3 and CPAM-12 deposited on SiO_(2) and Au substrates were 24.3 and 38.1 nm,respectively.When the K^(+)and Ca^(2+)concentrations increased from 10 and 1 mmol·L^(-1) to 100 and 10 mmol·L^(-1),Rq increased from 80.4 and 120.0 nm to 124.0 and 145.0 nm,respectively.In the morphology map,the molecular chains of PAM transformed from linear dendrites to point blocky structures.It was demonstra
作者
饶博
邹文杰
赵伟
余可馨
RAO Bo;ZOU Wenjie;ZHAO Wei;YU Kexin(National Institute of Clean and Low Carbon Energy,State Key Laboratory of Water Resource Protection and Utilization in Coal Mining,Beijing 102211,China;School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China)
出处
《工程科学学报》
EI
CSCD
北大核心
2024年第6期1012-1023,共12页
Chinese Journal of Engineering
基金
煤炭开采水资源保护与利用国家重点实验室开放基金资助项目(GJNY-20-113-12)
北京科技大学青年教师国际交流成长计划资助项目(QNXM20220013)
国家自然科学基金资助项目(51604019)。
关键词
紫外分光光度法
聚丙烯酰胺
浓度检测
溶液离子
原子力显微镜(AFM)
ultraviolet spectrophotometry method
polyacrylamide
concentration detection
solution ion
atomic force microscope(AFM)
