摘要:
The present invention relates to a method of preparing adsorbent particles formed from expanded plastics materials, said particles comprising cellular structures that are open at their surface, characterized in that a material constituted by agglomerated beads of said expanded material and having smooth surfaces is rasped into fine chips. The present invention also relates to adsorbent particles formed from an expanded plastics material comprising cellular structures that are open at their surface, characterized in that they are in the form of fine chips, preferably with a dimension of 0.8 mm to 4 mm, said open cellular structures represent more than 80% of the visible surface area of said chips. In a method of treating soil polluted with hydrocarbons, the following steps are carried out, in which: 1) said polluted soil is mixed with adsorbent particles according to the invention; and 2) said adsorbent particles charged with hydrocarbons are separated from the depolluted soil.
摘要:
Methodology for the extraction of metallic elements from solid and liquid metal-contaminated starting material such as mineral ores, recyclable wastes, contaminated soils, engraving solutions, metal finishing solutions, battery manufacturing solutions, toxic wastes such as dusts producing through steelmaking processes by effectuating preferably prolonged contacting of such starting material with liquor compositions to cause the underlying structure of the starting material to be broken down. The contaminated starting materials are more susceptible to metal separation because the released metallic element are readily solubilized in the contacting liquor. Compositions of the contacting liquor comprise caustic silicate solutions containing essentially saturating levels of silica. Once the plurality of metallic elements contained in the starting material have been solubilized, they tend to remain in solution, and then may be routinely extracted and removed using conventional extraction methodologies such as precipitation of insoluble salts, electrowinning, or electrodeposition.
摘要:
A method for removal of hydrocarbon materials from solid particulate soil contaminated with the hydrocarbon materials. The method comprises forming an aqueous slurry of a mixture of a hydrophobic adsorbent selected from foamed synthetic materials or natural materials which entrap gas, with the soil in the presence of water. The adsorbent has a density less than water. The slurry is mixed for a period of time, and a gravity separation of the adsorbent from the aqueous admixture thus obtained is effected.
摘要:
Heavy metals can be effectively complexed with a derivative of a fructan, which derivative contains complexing groups chosen from --X--CY--ZM, --X--CY--ZM, --X--CY--S--S--CY--X--Q, --PY'(--Z'M).sub.2, --SO.sub.3 M and --NR--CH.sub.2 --COOM, where M is a metal or hydrogen, Q denotes the residue of an alcohol or polyol, R is hydrogen or carboxymethyl and X, Y, Y', Z and Z', independently of one another, are O, S or NH and at least one of X, Y and Z is S, with a degree of substitution of 0.1-2.5. The complexing groups are in particular xanthate, xanthide or dithiocarbamate groups.
摘要:
A composition is provided which has been formulated to render non-hazardous surfaces which are coated with lead-based paints or surface soil which is contaminated with lead compounds. The composition is an aqueous mixture comprising hydrogen peroxide, ammonium hydroxide, nitric acid and acetic acid. The composition is effective on surfaces which may be comprised of wood, metal, concrete, wallboard or plaster without destroying the integrity of these surfaces.
摘要:
Disclosed is a method and apparatus for the continuous remediation of a site contaminated with a hazardous substance. The remediation apparatus includes a material selectively permeable to the hazardous substance located at the site. Once isolated, the hazardous substance is removed to a remote vessel by utilization of an automated gas-injection system. The remediation apparatus also incorporates a valve configured to protect the system from detrimental, and potentially dangerous, overloadings of hazardous substances.
摘要:
A method is provided to render non-hazardous surface soil which is contaminated with lead compounds. The soil is treated by applying an aqueous composition comprising hydrogen peroxide, ammonium hydroxide, nitric acid and acetic acid and allowing said composition to migrate through the soil.
摘要:
The present invention relates to a process for cleaning mercury-contaminated soils that is simple, efficient and safe to use. This process can also be used to clean soils contaminated with additional metals, such as zinc, copper and lead, at a lower pH. The present invention involves screening the contaminated soil to remove unwanted materials, leaching the contaminated soils with hypochlorite in a screw reactor, thickening, leaching with hypochlorite and sodium chloride, thickening again and then separating the mercury-containing liquids from the clean soil. This invention also relates to a process which uses sulfide to treat the mercury-containing liquids.
摘要:
A surfactant which is the reaction product of a hydrocarbyl-substituted succinic anhydride or a reactive equivalent thereof with at least one water-dispersible amine-terminated poly(oxyalkylene), is effective for use in soil remediation.
摘要:
A recycling system treats petrochemical types of hazardous waste for disposal. Such waste typically includes in large part, a mixture of hydrocarbons, water, solids (soil particulate), and metals. The recycling system separates the water, solids, hydrocarbons, and metals from one another. The recycling system includes the following processing steps:(1) mixing the hazardous waste with a water-miscible washing medium, and agitating the mixture for separating water and some hydrocarbons from solids;(2) removing hydrocarbons from solids by mixing the solid/hydrocarbons with a washing medium that is nonmiscible with water, and agitating the mixture for dissolving hydrocarbons in the solids;(3) removing metals from the separated solids by mixing the separated solids with an acidic washing medium, and agitating the mixture for dissolving metals from the separated solids into liquid solution; and(4) subjecting the separated solids to an alkaline washing solution for neutralizing acidity in the separated solids, and thereafter drying the separated solids for removal of moisture for disposal of the separated solids.Processing in accordance with the invention, provides separated water and soil particulate substantially free of contamination by hydrocarbons and/or toxic/RCRA metals, and thus may be reintroduced into the environment, the water sewered, and the metals recycled.