Decontamination basics

Chemical Separation. A reprocessing facility typically utilizes multiple extraction/reextraction (stripping) cycles for the recovery and purification of uranium and plutonium. For example, a co-decontamination and partitioning cycle is followed by one or more cycles of uranium and plutonium purification. The basic process is illustrated in Figure 3. 

Decontamination Neutral or slight basic solutions with sulfides, such as sodium sulfide. Do not use acidic solutions for decontamination acids reduce PS to CX, a blister agent. 

Most toxins are readily destroyed by high pH (i.e., basic solutions), especially when used in combination with a strong oxidizing agent. For this reason, undiluted household bleach is an excellent agent for decontamination of these agents. Ensure that the bleach solution remains in contact with the toxin for a minimum of 10 minutes. 

Eventually first responder personnel on scene will have to answer the basic question Do you have an attack or not Unlike exposure to chemical agents, exposure to biological agents does not require immediate removal of victims clothing and gross decontamination. With biological agents, inhalation is the most common route of entry to a victim s contamination. 

Figure 12.5 illustrates the basic components of the Purex process three purification cycles for both uranium and plutonium are shown. High levels of beta and gamma radioactivity are present only in the first cycle, in which 99.9% of the fission products are separated. The other two cycles, based upon the same chemical reactions as the first cycle, obtain additional decontamination and overall purity of the uranium and plutonium products. 

For many years, pressurized steam(autoclaving) at 120 °C for 30 minutes has been the basic method for sterilizing instruments and decontaminating materials. When autoclaving is not possible, as is the case with lensed instruments and materials containing plastic and rubber, ethylene oxide— diluted with either fluorocarbon or carbon dioxide to diminish explosive hazard—was used at 440-1200 mg/L at 45-60 °C with 30-60% relative humidity. The higher concentrations have been used to increase penetration. 

The basic experimental studies of the interactions between organophosphorus compounds and metal oxide surfaces have been carried out intensively during the last several years. Metal oxides, such as MgO, AI2O3, FeO, CaO, Ti02 a-Fe203, ZnO, and WO3, are currently under consideration as destructive adsorbents for the decontamination of chemical warfare agents [46, 47], For example, several studies have addressed adsorption of dimethyl methylphosphonate (DMMP) (a widely used model compound for the simulation of interactions of phosphate esters with a surface) on the surface of these metal oxides [48-60], In most of these works, the authors have observed that, at first, DMMP is adsorbed molecularly via hydrogen... 

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