Abstract: A method is provided for the treatment of contaminated materials such as impounded sludges and contaminated soils by thermal desorption wherein a solid matrix is subjected to the action of superheated steam in a closed vessel, a gas stream comprising superheated steam is recirculated to the vessel and recirculation of the superheated steam is continued until organic constituents are separated therefrom to predetermined concentrations that are environmentally insignificant and within the limits prescribed by governmental regulations.

Abstract: A method and apparatus are provided for remediating contaminated soil having volatilizable organic pollutants in a heated treatment zone, preferably a rotary drum, in gas/solids contact with superheated steam. Treatment gases from the treatment zone are repressurized and reheated for reuse in the treatment zone. Superheated steam is maintained in a closed loop and is maintained at superheated conditions. Vaporized organic pollutants and superheated steam are removed from the closed loop of superheated steam for cooling and condensation to condense water and condense liquid volatilizable organic pollutants and uncondensed organic pollutant vapors.

Abstract: A method for treating a pulp and paper manufacturing stream to remove colorants therefrom comprises: contacting the stream with a first adsorbent comprising the calcined product of a compound having the formula: A.sub.w B.sub.x (OH).sub.y C.sub.z.nH.sub.2 O, wherein A represents a divalent metal cation; B a trivalent metal cation; C a mono- to tetravalent anion; and w, x, y, z and n satisfying the following: 0<z.ltoreq.x.ltoreq.4.ltoreq.w.ltoreq.1/2y and 12.gtoreq.n.gtoreq.1/2(w-x); then contacting the stream with a second adsorbent consisting essentially of activated carbon. On a preferred basis, the first contacting adsorbent is a hydrotalcite derivative made by reacting activated magnesia with an aqueous solution of aluminate, carbonate, and hydroxyl anions before calcining at one or more temperatures between about 400.degree.-650.degree. C.

Abstract: Activated carbon regeneration is carried out in a downwardly moving bed with superheated steam moving upwardly through the bed. The superheated steam is maintained in a closed loop which comprises the steam treatment vessel, a steam pump and a steam superheater. The superheated steam is supplied at low pressure (e.g. less than about 10 psig) and provides the heat for volatilizing water and desorbed organic volatiles. The resulting dry, partially regenerated activated carbon may be re-used directly, but preferably is treated in a vacuum chamber to remove residual water and additional adsorbate.

Abstract: Method and apparatus for in-situ regeneration of particulate adsorbent in a vessel including: heating the adsorbent, passing inert gas through heated absorbent to collect vaporized adsorbate, chilling the inert gas to condense adsorbate, thereafter lowering the pressure within the vessel, collecting withdrawn gases containing volatilized adsorbate, and chilling the withdrawn gases to condense adsorbate.

Abstract: A relatively solid, stable biomass reaction product is provided produced from microorganisms having metal uptake properties when contacted by an aqueous solution containing metal cations. The biomass reaction product is produced by treating cells thereof with a caustic solution, whereby the biomass reaction product after drying is characterized in the particulate state of having substantially enhanced uptake of metal cations from aqueous solutions as compared to the metal uptake property of the microorganism before treatment. The biomass reaction product in the particulate state is preferably immobilized in an insoluble binder.

Abstract: A relatively solid, stable biomass reaction product is provided produced from microorganisms having metal uptake properties when contacted by an aqueous solution containing metal cations. The biomass reaction product is produced by treating cells thereof with a caustic solution, whereby the biomass reaction product after drying is characterized in the particulate state of having substantially enhanced uptake of metal cations from aqueous solutions as compared to the metal uptake property of the microorganism before treatment. The biomass reaction product in the particulate state is preferably immobilized in an insoluble binder.

Abstract: A relatively solid, stable biomass reaction product is provided produced from microorganisms having metal uptake properties when contacted by an aqueous solution containing metal cations. The biomass reaction product is produced by treating cells thereof with a caustic solution, whereby the biomass reaction product after drying is characterized in the particulate state of having substantially enhanced uptake of metal cations from aqueous solutions as compared to the metal uptake property of the microorganism before treatment.

Abstract: A relatively solid, stable biomass reaction product is provided produced from microorganisms having metal uptake properties when contacted by an aqueous solution containing metal cations. The biomass reaction product is produced by treating cells thereof with a caustic solution, whereby the biomass reaction product after drying is characterized in the particulate state of having substantially enhanced uptake of metal cations from aqueous solutions as compared to the metal uptake property of the microorganism before treatment.