Mineral sorbents, natural

Flg.4. The purification variation of liquid hydrocarbons from toxic admixture depending on sorbent nature 1 - carbon, 2 - mineral, 3 -catbonmineral... 

Natural organic sorbents — Natural materials such as peat moss, straw, and sawdust that can be used to recover spilled oil. Natural sorbents generally absorb three to six times their weight in oil by virtue of the criss-cross arrangement of fibres within the material. All natural sorbents absorb water as well as oil, however, and may sink when saturated with water. Indiscriminate used of natural sorbents can add to the problems of oil spill cleanup. Synthetic sorbents are usually favoured due to their greater capacity for oil and relative ease of recovery. (See also Mineral-based sorbents, Synthetic organic sorbents.)... 

Sorbent — A substance that either adsorbs or absorbs another substance. Specifically, it is a natural organic, mineral-based, or synthetic organic material used to recover small amounts of oil that have been spilled on land or water surfaces or stranded on shorelines. (See also Mineral-based sorbents, Natural organic sorbents, Synthetic organic sorbents.)... 

Aripov, E. A. Natural Mineral Sorbents, Their Activation and Modification Fan Tashkent, 1970. 

The use of surfactant-modified zeolite (SMZ) as a permeable barrier sorbent may offer several unique advantages when dealing with mixed contaminant plumes. Zeolites are hydrated aluminosilicate minerals characterized by cage-like structures, high internal and external surface areas, and high cation exchange capacities. Both natural and synthetic zeolites find use in industry as sorbents, soil amendments, ion exchangers,... 

Radionuclide transport in natural waters is strongly dependent on sorption, desorption, dissolution, and precipitation processes. The first two sections discuss laboratory investigations of these processes. Descriptions of sorption and desorption behavior of important radionuclides under a wide range of environmental conditions are presented in the first section. Among the sorbents studied are basalt interbed solids, granites, clays, sediments, hydrous oxides, and pure minerals. Effects of redox conditions, groundwater composition and pH on sorption reactions are described. 

Deviations from organic carbon correlations at these Iow/qc values have been attributed to sorption at mineral surfaces (6, 9). Furthermore, the reliability of K(l( predictions at higher/oc values may be affected by differences in sorption behavior attributed to differences in the organic matter associated with different types of natural. solid phases and, potentially, with different fractions of any particular natural sorbent (3, 10, 11). 

The pH range of minimum solubility of the uranyl minerals is also the pH range of maximal U(VI) sorption on most important natural sorbents, including organic matter (van der Weijden and Van Leeuwen 1985), Fe(III) oxyhydroxides, Mn and Ti oxyhydroxides, zeolites and clays (cf. Langmuir 1978 Turner 1995). In terms of approximate values, where /f (ml/g) = (wt adsorbed/wt sor-... 

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