Colloidal sulphur production by electrochemical oxidation of sulphide in a swirling flow reactor

A cylindrical reactor with swirling flow is tested for the production of colloidal sulphur via the oxidation of sulphide ions with a concentration of 2 g dm−3 in alkaline solutions...

Physicochemically modified peat by thermal and oxidation processes as an active material for purification of wastewaters from certain hazardous pollutants

The physicochemical modification of peat through thermal and oxidation processes was carried out, in order to obtain new, inexpensive and active material for purification of different types of waters. During the modification, surface chemical compounds of Shilov type were formed. Batch adsorption properties and suitability of physicochemically modified peat (PCMP) for odor removal were tested in aqueous solutions of H2S and colloidal sulphur. Additionally, PCMP was tested in the removal of As(V) which is hazardous ingredient in contaminated waters. Possible mechanisms of pollutants binding include interactions, which lead to formation of adducts and clathrates. All these processes are elucidated in detail. The results showed that the obtained material can be used for the removal of sulphide, colloidal sulphur and As(V) from different types of waters.

Immobilization of soil mercury by colloidal sulphur in the laboratory experiment

The results of the laboratory pot experiments on soil mercury (Hg) immobilisation with a non-toxic and price-reasonable agent — colloidal sulphur (S) water suspension, are presented. It was shown that fertilisation with small agrochemical doses of colloidal S reduces excess Hg effectively as follows: in interstitial waters by a factor 2 – 12 times for total Hg, and 22– 680 times for “reactive” Hg; in stems and leaves of oats – 7 – 22 times; and in moss bags, reflecting soil Hg degassing, 7 – 15 times, for the most heavily Hg-spiked soils. The results obtained allowed to conclude that the immobilization of Hg occurs through Hg binding to the newly formed S-bearing functional groups in humic acids and/or sulphides.