Catalytic Hydrogel Membrane Reactor for Treatment of Aqueous Contaminants

Article

Abstract

Heterogeneous hydrogenation catalysis is a promising approach for treating oxidized contaminants in drinking water, but scale-up has been limited by the challenge of immobilization of the catalyst while maintaining efficient mass transport and reaction kinetics. We describe a new process that addresses this issue: the catalytic hydrogel membrane (CHM) reactor. The CHM consists of a gas- permeable hollow-fiber membrane coated with an alginate- based hydrogel containing catalyst nanoparticles. The CHM benefits from counter-diffusional transport within the hydro- gel, where H2 diffuses from the interior of the membrane and contaminant species (e.g., NO2−, O2) diffuse from the bulk aqueous solution. The reduction of O2 and NO2− were investigated using CHMs with varying palladium catalyst densities, and mass transport of reactive species in the catalytic hydrogel was characterized using microsensors. The thickness of the “reactive zone” within the hydrogel affected the reaction rate and byproduct selectivity, and it was dependent on catalyst density. In a continuously mixed flow reactor test using groundwater, the CHM activity was stable for a 3 day period. Outcomes of this study illustrate the potential of the CHM as a scalable process in the treatment of aqueous contaminants.

Attributes

Attribute NameValues
Creator
  • Randal Marks

  • Joseph Seaman

  • Patricia Perez-Calleja

  • Junyeol Kim

  • Robert Nerenberg

Journal or Work Title
  • Environmental Science & Technology

Volume
  • 53

First Page
  • 6492

Last Page
  • 6500

ISSN
  • 0013-936X

Subject
  • Titan TEM

Publisher
  • American Chemical Society

Date Created
  • 2019-08-20

Language
  • English

Departments and Units
Record Visibility and Access Public
Content License
  • All rights reserved

Digital Object Identifier

doi:10.1021/acs.est.9b01667

This DOI is the best way to cite this article.