Solvents decontamination

Ballard, J.G. and Hawthorne, S.H. Solvent Decontamination of PCB Electrical Equipment, Canadian Electrical Association Engineering and Operating Division 1981 Part 1, 81-A-66. 

Decontamination or disposal of clothing or equipment leaving a contaminated area [OSHA Reference, 120(k)(2)(iii)] Decontamination or disposal of equipment and solvents used for decon [OSHA Reference, 120(k)(4)]... 

SFE. SFE has been established as the extraction method of choice for solid samples. The usefulness of SFE for soil samples has been demonstrated for carbamate,organophosphorus and organochlorine pesticides. However, SFE is more effective in extracting nonpolar than polar residues. In order to obtain a greater extraction efficiency for the polar residues of imidacloprid, the addition of 20% methanol as modifier is required. Extraction at 276 bar and 80 °C with a solvent consisting of supercritical carbon dioxide modified with methanol (5%) for 40 min gives a recovery of 97% (RSD = 3.6%, n = 10). It is possible to use process-scale SFE to decontaminate pesticide residues from dust waste. ... 

Decontamination Complete cleansing of the skin with soap and water at the earliest opportunity. If washing is impossible, use the M258A1, M258, or M291 skin decontamination kit. Symptoms may appear as late as 36 h after contact exposure, even if the skin is washed within an hour. In fact, a delay in onset of several hours is typical. Use this time to prepare for the possibility of a widespread outbreak 6-24 h after the attack. Decontaminate bulk quantities of BZ with caustic alcohol solutions. If BZ or other belladonnoids are used as free bases, decontamination will require a solvent, such as 25% ethanol, 0.1 N hydrochloric acid, or 5% acetic acid. 

They may be incompatible with the clothing or equipment being decontaminated (e.g., some organic solvents can permeate or degrade protective clothing)... 

The biocatalyst may be supported on a Lewis acid. Elemental sulfur is removed from the liquid hydrocarbons and the recovered solvent is counter-currently washed with water in a separate unit. Prior to reuse, the solvent is distilled to decontaminate it from remaining water or sulfur slurry. The treated product not only has a reduced concentration of organic sulfur compounds, but also its viscosity is reduced. 

Keywords chemical warfare agents, decontamination, detoxification, human skin, chemisorption, oxidation, detergents, alcoholates, aprotic solvents... 

Due to the limited extent of this paper, we mention only some positive results achieved in the orientation to two main directions i.e. to oxidative principles and to alcoholates in aprotic solvents. The research of oxidative principles (see e.g. [9]), involved the use of compounds with active chlorine, active iodine, peroxo-compounds, various mixtures of these compounds, as well as the use of oxidative agents with enhancing solubility and thus decontamination efficiency by adding detergents. It can... 

Table 7. Decontamination efficiency of alcoholates in aprotic solvents.

The solvent extraction process that uses TBP solutions to recover plutonium and uranium from irradiated nuclear fuels is called Purex (plutonium uranium extraction). The Purex process provides recovery of more than 99% of both uranium and plutonium with excellent decontamination of both elements from fission products. The Purex process is used worldwide to reprocess spent reactor fuel. During the last several decades, many variations of the Purex process have been developed and demonstrated on a plant scale. 

Thus, the 1-naphthyl acetate activity from the cigarette beetle yeast does have properties, especially the solvent stability, that are likely to promote use for decontamination of lipophilic toxins. In addition, this activity (and in some cases additional molecular forms detected by gel electrophoresis) can be stimulated (based on higher activity relative to solvent controls) by malathion,... 

The Extraksol process is a batch, solvent extraction technology that extracts organic contaminants from unconsolidated solids. The Extraksol system is mobile, offering flexibility in treating soils and sludges to different decontamination levels. 

SOLFIX is an ex situ stabilization technology that treats heavy metals by reacting contaminated soils and sediments with cement, pozzolanic materials, and other additives to chemically immobilize contaminants into an insoluble form. SOLFIX can be used either as a stand-alone technology or it can be incorporated with Hydro-SEP (a sediment washing technology) and ORG-X (a solvent extraction technology) into a three-step remediation process termed integrated sediment decontamination system (ISDS). 

Decontaksolv is a mobile autoclave/solvent extraction system for decommissioning polychlorinated biphenyl (PCB) contaminated equipment. Decontaksolv was developed and commercialized by Sanexen Environmental Services, Inc., in Canada in the 1980s. From 1985 to 1994 it was used to decontaminate 3 million kilograms of PCB-contaminated equipment. 

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