Fluorescence spectroscopic studies of the effect of granular activated carbon adsorption on structural properties of dissolved organic matter fractions
نویسندگان
چکیده
This work investigated the effect of granular activated carbon adsorption (GACA) on fluorescence characteristics of dissolved organic matter (DOM) in secondary effluent, by means of excitation–emission matrix (EEM) spectra, the fluorescence regional integration (FRI) method, synchronous spectra, the fluorescence index defined as the ratio of fluorescence emission intensity at wavelength 450 nm to that at 500 nm at excitation (lex)= 370 nm, and the wavelength that corresponds to the position of the normalized emission band at its half intensity (l0.5). DOM in the secondary effluent from the North Wastewater Treatment Plant (Shenyang, China) was fractionated using XAD resins into 5 fractions: hydrophobic acid (HPO–A), hydrophobic neutral (HPO– N), transphilic acid (TPI–A), transphilic neutral (TPI–N) and hydrophilic fraction (HPI). Results showed that fluorescent materials in HPO–N and TPI–N were less readily removed than those in the other fractions by GACA. The relative content of fluorescent materials in HPO–A, TPI–A and HPI decreased whereas that in HPO– N and TPI–N increased as a consequence of GACA. Polycyclic aromatics in all DOM fractions were preferentially absorbed by GACA, in comparison with bulk DOM expressed as DOC. On the other hand, the adsorption of aromatic amino acids and humic acid-like fluorophores exhibiting fluorescence peaks in synchronous spectra by GACA seemed to be dependent on the acid/neutral properties of DOM fractions. All five fractions had decreased fluorescence indices as a result of GACA. GACA led to a decreased l0.5 value for HPO–A, increased l0.5 values for HPO–N, TPI–A and HPI, and a consistent l0.5 value for TPI–N.
منابع مشابه
Adsorption of Volatile Organic Compounds from Aqueous Solution by Granular Activated Carbon (GAC) in Batch System
متن کامل
Modification of activated carbon by cold plasma and its effect on the adsorption of toluene
Abstract Background and aims: Clean air is one of the basic needs for human health and well-being. However, along with economic growth and development, transportation, urbanization and energy consumption have also risen and provide many concerns such as air pollution, which require urgent and wide attention. Air pollution in the worldwide is considered as a risk factor for human health and one...
متن کاملOrganic matter from biofilter nitrification by high performance size exclusion chromatography and fluorescence excitation-emission matrix
A combination of high performance size exclusion chromatography with organic carbon detector and ultraviolet detector coupled with peak-fitting technique and fluorescence excitation-emission matrix spectrometry applied fluorescence regional integration method was conducted to determine the characteristics of organic matter during nitrification. The batch scale of bionet nitrification without or...
متن کاملComparative potential of black tea leaves waste to granular activated carbon in adsorption of endocrine disrupting compounds from aqueous solution
The adsorption properties and mechanics of selected endocrine disrupting compounds; 17 β-estradiol, 17 α – ethinylestradiol and bisphenol A on locally available black tea leaves waste and granular activated carbon were investigated. The results obtained indicated that the kinetics of adsorption were pH, adsorbent dose, contact time and temperature dependent with equilibrium being reached at 20 ...
متن کاملRemoval of dissolved organic matter by granular-activated carbon adsorption as a pretreatment to reverse osmosis of membrane bioreactor effluents.
The adsorption of dissolved organic matter (DOM) on granular-activated carbon (GAC) as a pretreatment to reverse osmosis (RO) desalination of membrane bioreactor (MBR) effluents was studied in lab- and pilot-scale columns. The pattern and efficiency of DOM adsorption and fate of the hydrophobic (HPO), transphilic (TPI) and hydrophilic (HPI) fractions were characterized, as well as their impact ...
متن کامل