Prof. Shlomo Nir

Ongoing Research:

Water Purification from Organic Contaminants by Micelle-Clay Complexes

We have developed a new clay-based technology for purification of organic-contaminated water, which is effective for the removal of many pollutants, including anionic organic contaminants and dissolved organic matter (DOM), and which is expected to perform better than activated carbon. This technology is based on a complex between micelles of an organic cation and a clay mineral, such as montmorillonite. Column filters (25 cm) made of a mixture of quartz sand and BDMHDA micelle-clay complex removed 89% to 99.9% of the neutral and anionic pollutants from initial solutions whose concentrations varied over 6 orders of magnitude between 500 mg/L and 0.2 μg/L. In eleven cases where a comparison was made with an equivalent filter filled with activated carbon, the latter removed these pollutants with a significantly smaller efficiency. A computer program which combines flow and adsorption/desorption in a filter was written and employed to yield estimates of efficiency of removal and capacity under a variety of situations. Preliminary results showed that the micelle-clay complex was able to remove from water bacterial cells both in suspension and by passing through a filter.

Development of Environmentally-Friendly Herbicide Formulations

Leaching, phytotoxicity and weed control of new formulations of herbicides: Laboratory and field experiments (with Y. Mishael and B. Rubin (Dept. of Field Crops, Vegetables and Genetics)). Formulations which reduce significantly leaching and required dose of the neutral herbicides, metolachlor and bramicil and the anionic ones sulfentrazone and emazapyr were designed. Slow release of the herbicide to the environment maintained the herbicidal activity in the top soil, as measured by bioassays using Setaria viridis and Triticum sativum as test plants. Laboratory and field experiments showed improved weed control.

This file last modified 09/10/06