Molecular-Weight-Fractionation Characteristics and Coagulation

Mar 7, 2018 - The current study focuses on the evaluation of the hard DOM and colorants based on their molecular weight fractionation, which facilitat...
6 downloads 8 Views 1005KB Size
Subscriber access provided by UNIV OF NEW ENGLAND ARMIDALE

Separations

Molecular weight-fractionation characteristics and coagulation behaviors of bio-recalcitrant dissolved organic matter and colorants in cassava distillery wastewater Yu Chen, Ming Zhang, Li Xie, Zhou Wang, and Qi Zhou Ind. Eng. Chem. Res., Just Accepted Manuscript • DOI: 10.1021/acs.iecr.8b00287 • Publication Date (Web): 07 Mar 2018 Downloaded from http://pubs.acs.org on March 7, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 28 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Industrial & Engineering Chemistry Research

Molecular weight-fractionation characteristics and coagulation behaviors of bio-recalcitrant dissolved organic matter and colorants in cassava distillery wastewater

Yu Chen†, Ming Zhang*,†,‡, Li Xie*,†, Zhou Wang†, Qi Zhou†



State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory

of Yangtze River Water Environment, Institute of Biofilm Technology, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, PR China ‡

College of Environment, Zhejiang University of Technology, Hangzhou 310014,

China

Corresponding author: *Ming Zhang, E-mail address: [email protected]. Phone: +86 15824122236. *Li Xie, E-mail address: [email protected]. Tel: +86 021 65982689.

1

ACS Paragon Plus Environment

Industrial & Engineering Chemistry Research 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Abstract

The bio-recalcitrant dissolved organic matter (DOM) and colorants in the bio-chemically treated effluent, featured as their complex and indefinite composition, are drawing an increasingly environmental concern in the distillery industry. The current study focuses on the evaluation of the hard DOM and colorants based on their molecular weight fractionation, which facilitates the colorant identification and the mechanism exploration in the subsequent coagulation process. It was found that the DOM was distributed most in the MW range of 1-5 kDa whereas least in the MW below 1 kDa; and the fluorescent components in the bio-chemically treated distillery wastewater mainly distributed in low MW (100, 10-100, 5-10 and 1-5 kDa were obtained by collecting the concentrate above the membranes of 100, 10, 5 and 1kDa cut-off, named Fr-100, Fr-10, Fr-5 and Fr-1, respectively; and the MW fraction below 1 kDa was the filtrate of 1 kDa membrane, named Fr-0. The concentration factor of the ultra-filtration was controlled at 1/16. The DOC and color in different MW fractions were measured and listed in Table 1. Table 1. DOC and color of the five components with different MW fractions. Fraction Parameter

Fr-100

Fr-10

Fr-5

6

ACS Paragon Plus Environment

Fr-1

Fr-0

Page 7 of 28 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Industrial & Engineering Chemistry Research

DOC (mg/L) Color (Pt-Co unit)

395.5±0.4 2060±14

377.7±3.3 1927±2

332.7±2.7 1393±3

1663.0±12.7 9987±20

49.1±0.3 46±1

The distributions of DOC and colorants in molecular weight were calculated by Eq.1-2 (take DOC as an example).

η ( DOC, MW (b − a),%) =

DOC (MW < a) V1 / V − DOC (MW < b) V2 / V ×100% DOC (T )

V2 = V1 (1 − γ )

(1)

(2)

where η represents the percentage of MW (b-a) component of the solution before fractionation, a and b represent different MWs (a>b), when b equals to 100 kDa, a variable is meaningless, the sample "MW