Adsorption of N-nitrosodimethylamine precursors by powdered and granular activated carbon.
نویسندگان
چکیده
Activated carbon (AC) has been shown to remove precursors of halogenated disinfection byproducts. Granular and powdered activated carbon (GAC, PAC) were investigated for their potential to adsorb N-nitrosodimethylamine (NDMA) precursors from blends of river water and effluent from a wastewater treatment plant (WWTP). At bench scale, waters were exposed to lignite or bituminous AC, either as PAC in bottle point experiments or as GAC in rapid small-scale column tests (RSSCTs). NDMA formation potential (FP) was used as a surrogate for precursor removal. NDMA FP was reduced by 37, 59, and 91% with 3, 8, and 75 mg/L of one PAC, respectively, with a 4-h contact time. In RSSCTs and in full-scale GAC contactors, NDMA FP removal always exceeded that of the bulk dissolved organic carbon (DOC) and UV absorbance at 254 nm. For example, whereas DOC breakthrough exceeded 90% of its influent concentration after 10,000 bed volumes of operation in an RSSCT, NDMA FP was less than 40% of influent concentration after the same bed life of the GAC. At full or pilot scale, high NDMA FP reduction ranging from >60 to >90% was achieved across GAC contactors, dependent upon the GAC bed life and/or use of a preoxidant (chlorine or ozone). In all experiments, NDMA formation was not reduced to zero, which suggests that although some precursors are strongly sorbed, others are not. This is among the first studies to show that AC is capable of adsorbing NDMA precursors, but further research is needed to better understand NDMA precursor chemical properties (e.g., hydrophobicity, molecular size) and evaluate how best to incorporate this finding into full-scale designs and practice.
منابع مشابه
بررسی حذف کروم شش‌ظرفیتی از محلول‌های آبی با استفاده از کربن فعال گرانولی و پودری تولید‌شده از دانه اسپند
Background and Objectives: Because of toxical and hazardous properties of hexavalent chromium (Cr(VI)), its removal by an economical and efficient method is necessary. The use of activated carbon, as an adsorbent, is a common and effective method for hexavalent chromium removal. Thus the aim of this study was to produce granular and powdered activated carbon form Peganum Harmala and compare the...
متن کاملAdsorption of Volatile Organic Compounds from Aqueous Solution by Granular Activated Carbon (GAC) in Batch System
متن کامل
Comparative 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 کاملExperimental and Theoretical Study on the CH4 Adsorption by Granular and Microporous Activated Carbon
Adsorbed natural gas (ANG) by Granular Activated Carbon (GAC) has been widely investigated as an alternative to CNG and LNG technologies for storage and transportation of natural gas. In the present work, a theoretical and experimental study was conducted to accurately determine the amount of adsorption of CH4 by GAC. To carry out the experiments, the volumetric method was used up to 4 MPa at c...
متن کاملRemoval of copper (II) from aqueous solutions by adsorption onto granular activated carbon in the presence of competitor ions
In this work, the removal of copper from an aqueous solution by granular activated carbon (GAC) in the presence of competitor ions was studied. A batch adsorption was carried out and different parameters such as pH, contact time, initial copper concentration and competitor ions concentration were changed to determine the optimum conditions for adsorption. The optimum pH required for maximum ads...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Environmental science & technology
دوره 46 22 شماره
صفحات -
تاریخ انتشار 2012