Nuclear Non-proliferation Import and Export Control Regulations — A.2.4.6
A.2.4.6 Especially designed or prepared systems, equipment and components for use in chemical exchange or ion exchange enrichment plants, including: A.2.4.6.1 Liquid-liquid exchange columns (chemical exchange) Countercurrent liquid-liquid exchange columns with mechanical power input, especially designed or prepared for uranium enrichment using the chemical exchange process. For corrosion resistance to concentrated hydrochloric acid solutions, these columns and their internals are generally made of or protected by suitable plastic materials (such as fluorinated hydrocarbon polymers) or glass. The stage residence time of the columns is normally designed to be 30 s or less. A.2.4.6.2 Liquid-liquid centrifugal contactors (chemical exchange) Liquid-liquid centrifugal contactors especially designed or prepared for uranium enrichment using the chemical exchange process. Such contactors use rotation to achieve dispersion of the organic and aqueous streams and then centrifugal force to separate the phases. For corrosion resistance to concentrated hydrochloric acid solutions, the contactors are generally made of or protected by suitable plastic materials (such as fluorinated hydrocarbon polymers) or glass. The stage residence time of the centrifugal contactors is normally designed to be 30 s or less. A.2.4.6.3 Uranium reduction systems and equipment (chemical exchange) (a) especially designed or prepared electrochemical reduction cells to reduce uranium from one valence state to another for uranium enrichment using the chemical exchange process. The cell materials in contact with process solutions must be corrosion resistant to concentrated hydrochloric acid solutions; and (b) especially designed or prepared systems at the product end of the cascade for taking the U +4 out of the organic stream, adjusting the acid concentration and feeding to the electrochemical reduction cells. A.2.4.6.4 Feed preparation systems (chemical exchange) Especially designed or prepared systems for producing high-purity uranium chloride feed solutions for chemical exchange uranium isotope separation plants. A.2.4.6.5 Uranium oxidation systems (chemical exchange) Especially designed or prepared systems for oxidation of U +3 to U +4 for return to the uranium isotope separation cascade in the chemical exchange enrichment process. A.2.4.6.6 Fast-reacting ion exchange resins/adsorbents (ion exchange) Fast-reacting ion-exchange resins or adsorbents especially designed or prepared for uranium enrichment using the ion exchange process, including porous macroreticular resins, and pellicular structures in which the active chemical exchange groups are limited to a coating on the surface of an inactive porous support structure, and other composite structures in any suitable form including particles or fibres. These ion exchange resins/adsorbents have diameters of 0.2 mm or less and must be chemically resistant to concentrated hydrochloric acid solutions as well as physically strong enough so as not to degrade in the exchange columns. The resins/adsorbents are especially designed to achieve very fast uranium isotope exchange kinetics (exchange rate half-time of less than 10 s) and are capable of operating at a temperature in the range of 100°C to 200°C. A.2.4.6.7 Ion exchange columns (ion exchange) Cylindrical columns greater than 1 000 mm in diameter for containing and supporting packed beds of ion exchange resin/adsorbent, especially designed or prepared for uranium enrichment using the ion exchange process. These columns are made of or protected by materials (such as titanium or fluorocarbon plastics) resistant to corrosion by concentrated hydrochloric acid solutions and are capable of operating at a temperature in the range of 100°C to 200°C and pressures above 0.7 MPa (102 psi). A.2.4.6.8 Ion exchange reflux systems (ion exchange) (a) especially designed or prepared chemical or electrochemical reduction systems for regeneration of the chemical reducing agent(s) used