Removal of trace toxic and carcinogenic organic and inorganic pollutants from water

Book · Thu Jan 01 04:00:00 EST 1987

OSTI ID:5842581

Stevens, M R

Major pollutants of concern in water supplies are principally are of antropic origin and may be broadly divided classified as: (1) persistent organics, such as pesticides, and (2) toxic inorganic chemicals; e.g. heavy metals. Both classes of contaminants can undergo reactions with naturally occurring organics; e.g. humic substances, to yield complex compounds that may not be effectively removed by conventional water treatment operations. This research investigates removal of selected toxic and/or carcinogenic trace organic and inorganic pollutants by granulated activated carbon (GAC). This included the development of equilibrium and rate data relative to adsorption of polychlorinated biphenyls (PCBs), and several toxic metals including, cadmium, lead, and zinc. The effectiveness of activated carbon for removal of PCBs from water is adversely affected by background humic substances. Mechanisms responsible for this may be competition and/or complexation between humic substances and PCB molecules. Results of high pressure mini-column (HPMC) experiments indicate that calcium ions in a solution containing humic acid and PCB adversely affected PCB removals. This phenomenon may be due to interaction between the free PCB molecules and more strongly adsorbed calcium-humate-PCB complexes. Removal of trace cadmium, lead, and zinc by carbon-immobilized 8-hydroxyquinoline is far superior to that of virgin carbon. The Homogeneous Surface Diffusion Model (HPMC) was generally able to predict and simulate the dynamic performance of fixed-bed adsorbers for 2,2',4,5,5'-PCB. The model, however, was not able to satisfactorily predict column performance for the metals of interest.

• Research Organization: University of Southern California, Los Angeles (USA)
• OSTI ID: 5842581
• Country of Publication: United States
• Language: English

Related Subjects

520200* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
ACTIVATED CARBON
ADSORBENTS
ADSORPTION
AROMATICS
CADMIUM
CARBON
CHLORINATED AROMATIC HYDROCARBONS
ELEMENTS
HALOGENATED AROMATIC HYDROCARBONS
LEAD
METALS
NONMETALS
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
PESTICIDES
POLLUTION
SORPTION
WATER POLLUTION
ZINC