title: [Three-dimensional excitation emission matrix fluorescence spectroscopic characterization of loosely bound and tightly bound extracellular polymeric substances of sludge].
abstract: Three-dimensional excitation emission matrix fluorescence spectroscopy (3DEEM)was applied to characterize the loosely bound extracellular polymeric substances (LB-EPS) and tightly bound extracellular polymeric substances (TB-EPS) extracted from aerobic sludge in wastewater treatment. The results showed that three fluorescence peaks were identified in threedimensional excitation emission matrix fluorescence spectra of the LB-REPS and TB-EPS: peak B (lamda ex/ lamda em = 270-280 nm/345-360 nm), peak C (lamda ex/ lamda em = 330-340 nm/410-430 nm)and peak D (lamda ex/ lamda em = 390 nm/450-470 nm). The peak B was attributed to the protein-like fluorophores, peak C to the visible fulvic-like fluorophore and peak D to the humic-like fluorophore. Results of the peak intensity showed that the major component of the LB-EPS and TB-EPS is protein-like organic matter, then followed by (from high to low): fulvic-like organic matter and humic-like organic matter. The effects of both pH and concentration were significant to the 3DEEMs of LB-EPS and TB-EPS, but the degree is not the same. LB-EPS has the particular chemical structures which are different from the TB-EPS.
authors: Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China. oyem02@mails.tsinghua.edu.cn
authors: Er-ming
authors: EM
authors: Ouyang
authors: Wei
authors: W
authors: Wang
authors: Neng
authors: N
authors: Long
authors: Huai
authors: H
authors: Li