DENSIFICATION OF LMH-2.
Abstract
High-purity Li-doped BeH2 was successfully crystallized by means of hydrostatic compaction under moderate conditions of pressure, temperature and time. A hydrostatic pressure of only 42,000 psi proved sufficient to effect complete crystallization at 205 C in less than 4 hours; under conditions of 60,000 psi and 205 C, crystallization was complete within one hour. Increase in operating pressure from 42,000 to 115,000 psi gave a stepwise increase in product density from about 0.72 to 0.77 g/cc. A change in relative concentrations of the two known crystalline polymorphs occurred concurrently. Pre-treatment of the amorphous BeH2 feed by encapsulation proved necessary to successful crystallization. A completely satisfactory encapsulation process has not yet been defined, although a provisional technique employing pre-compaction fusion and encapsulation in aluminum foil and Teflon has performed satisfactorily at the laboratory scale. Hydrostatic compaction of a slurry of BeH2 in a hydrocarbon fluid was found to be ineffective. Addition of 2.5-3 wt % KF to high purity crystallization feed (96 wt % BeH2, 1.3 wt % Li) gave a product which crystallized at a rate only slightly higher than usual.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1966
- Accession Number
- AD0383282
Entities
People
- E. M. Marlett
- G. J. Brendel