Storage media issues

Also, to provide completeness to this study a H2 storage medium is needed. It is beyond the scope of this study to evaluate all possible H2 storage systems. The incorporation of a metal hydride system provides one legitimate model for the assessment of downstream H2 distribution systems. By incorporating a MH storage and delivery system in this, two significant issues requiring additional research have been identified in the review process ... 

In development or small clinical production runs, complete liquid medium may be most convenient. Economic issues may dictate that at large-scale powdered or liquid concentrate medium be used. Shipment and storage of large volumes of complete liquid medium is less practical at scales greater than 1000 L. 

One issue with the use of sodium hydride as a reagent in pilot and commercial operations is the storage and handling requirements for this material. Sodium hydride is typically obtained commercially as a 60% amalgam in mineral oil to stabilize the reagent. In the nevirapine process, the mineral oil tends to agglomerate with the product upon precipitation from the reaction mixture. An intermediate purification step was developed through use of DMF as a crystallization medium. The crude product was dissolved in hot DMF followed by charcoal treatment to absorb the residual mineral oil associated with the product. The charcoal was then removed by filtration followed by evaporative crystallization of the product. A final aqueous crystallization was carried out to remove residual quantities of DMF from the product by acidification with hydrochloric acid followed by treatment with caustic to precipitate the product. 

The plant possesses a duly issued license for types of activity related to processing of nuclear materials and the equipment of temporary storage facilities for medium- and high-level liquid waste, and to the handling of radioactive substances as individual units of the temporary storage facility for medium- and high-level waste are decommissioned. It holds a temporary permit from the Russian Federation State Academy of Sciences for all types of activity. 

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