Investigation of Natural Zeolitic Tuffs on their Ability for Sewage Cleaning Purposes

This study deals with the application of Jordanian natural zeolites in the removal of heavy metal ions and plant nutrients from polluted waters. The material used was brownish and reddish zeolitic tuffs. Both materials were found to be very different from each other in their chemical and mineralogical compositions. The untreated sample of reddish zeolitic tuff showed a very high capacity for ammonium adsorption (46g/kg) from an ammonium standard solution in comparison to the brownish tuff (20g/kg). In contrast, the adsorption capacities for NH4+ were highly decreased when the zeolitic tuff was agitated with a manure. Furthermore, phosphorus was also removed from the manure. The ammonium ions, which were absorbed were then extracted from the tuffs using tap or distilled water. The reddish tuff had an elution percentage of 87% while that of the brownish tuff was 76%. The first released the NH4+ ions more slowly than the latter. Similar results were obtained for the extraction process of ammonium ions, which were absorbed from the manure. It was found that when a greater amount of the tuffs was used, a slower extraction process was achieved. In contrast, the amount of phosphate extracted from the tuffs was not affected by the weight of zeolitic tuffs used, but a significant difference was observed when the distilled water (pH 5.5) was used. The evaluation of zeolitic tuffs for the removal efficiency of Pb2+, Cd2+, Cu2+, Ni2+ and Zn2+ from simple and complex solutions was done in a batch reactor and in an ion exchange column. In batch systems, the sample of untreated brownish tuff removed ions more efficiently from simple solutions containing only one type of ions (Cd2+, Cu2+, Ni2+ and Zn2+) than the reddish tuff. In contrast, Pb2+ ions were highly absorbed by both tuffs (145-150mg/g). The effects of counter (Ca2+ and Na+) ions had on the removal of metal ions are as follows: 1. The Pb2+ and Cu2+ ions absorbed were not affected by the presence of counter ion and were not dependent on the type of regeneration form used. 2. The amount of Zn2+, Cd2+ and Ni2+ absorbed was highly dependent on the regenerated-form of tuff used and was not affected by the presence of Ca2+ or Na+ ions. The results obtained from the test of both zeolitic tuffs in the different forms of regeneration in column process indicated that the brownish zeolitic tuff in Na-form had an especially high efficiency for removing metal ions. The extracted metal ions from the zeolitic tuffs are highly variable and dependent on the regeneration solution used (CaCl2, KNO3 or NaNO3) as well as the previously used form of zeolitic tuff. In general, more metal ions were removed from the Na-form of brownish zeolitic tuff, and this amount it was further increased by a second cycle of regeneration.

Level thesis:degree_level

thesis.doctoral

Grantor dc:publisher

Universität Oldenburg

Year

2000

Author dc:creator

• Rashdan, Zaid Ali Fadel ^Al^

• [Keine Schlagwörter von Autor/in vergeben.]

Repository record source_url

http://oops.uni-oldenburg.de/400

OAI identifier oai:identifier

oai:oops.uni-oldenburg.de:400