Accession Number:

ADA257798

Title:

Removal of Cadmium and Chromium from a Pretreated Wastewater with Reverse Osmosis

Descriptive Note:

Master's thesis

Corporate Author:

PURDUE UNIV LAFAYETTE IN

Personal Author(s):

Report Date:

1992-05-01

Pagination or Media Count:

90.0

Abstract:

The purpose of this research project was to investigate the removals of cadmiumII and chromiumVI from a simulated wastewater by reverse osmosis RO. The project was one very focused aspect of a major U.S. Navy multi-year research project aimed at achieving zero-discharge from its Industrial Wastewater Treatment Plants. The effects of varied operating conditions on the performance of a thin-film composite brackish water RO membrane were investigated feed solutions of 1000, 2000, and 3000 mgl NaCl 2000 mgl NaCl at pH 5, 6 and 7 and background feed composition solutions of NaCl and Na2SO4 at four different mix ratios. The effects of temperature in the range of 20 to 36 C, and operating pressures of 400, 300 and 200 psi were also investigated. In nearly all cases metal concentrations were 10 mgl a 100 mgl test was also performed. Typical RO behaviors were observed with water and solute permeation. Both water permeation and solute passage decreased with time due to membrane compaction. On the other hand, water permeation increased with applied pressure. The best rejections for the metals were obtained in feed solutions of sodium chloride and sodium sulfate. A maximum rejection of 99.9 percent was observed for cadmiumII at a feed solution mole fraction of approximately 0.95 sodium sulfate and a pH of 6. The highest chromiumVI rejection observed was 99.1 percent at a 0.5 mole fraction of sodium sulfate and pH of 6.

Subject Categories:

  • Inorganic Chemistry
  • Fluid Mechanics
  • Water Pollution and Control

Distribution Statement:

APPROVED FOR PUBLIC RELEASE