Chemical studies on SYNTHOIL process. Quarterly report, September 1--November 30, 1975

This is the first quarterly report of a two year program of a study in support of the Pittsburgh Energy Research Center's SYNTHOIL process for coal liquefaction. The overall program consists of three tasks: Task 1, ''Catalyst Improvement'' in which the mechanisms of catalyst deactivation and methods of reactivation will be explored; Task 2, ''Ash Effects'' in which the effect of the mineral content of coals on liquefaction will be assessed in autoclave experimens; and Task 3, ''Kinetic Studies'' in which a bench-scale reactor will be set up to study the effects of process parameters on the kinetics of hydrodesulfurization and liquefaction. Progress in each task area is reported. Various analytical techniques were evaluated for Task 1 with respect to their ability to analyze structural and compositional aspects of catalysts in the new, used, and regenerated conditions. Surface areas, pore volumes, and pore size distributions were measured and correlated with the microstructural features revealed by electron microscopy. The design of the autoclave facility for Task 2 was completed. The system will utilize a fail-safe concept that will permit operation within a manned laboratory area. The design of the modularized reactor system for Task 3 is nearly complete. Some of the significant design features are high-pressure strain gage transducers for pressure measurements, load cell gravimetric measurements of liquid transfer rates, intermediate position product-withdrawal facilities for both preheater and reactor, and digitization of analog instrumentation outputs for a data acquisition system. (auth

Testing of low Z coated limiters in tokamak fusion devices

Extensive testing on a laboratory scale has been used to select those coatings most suitable for this environment. From this testing which included pulsed electron beam heating, low energy ion bombardment and arcing, chemical vapor deposited coating of TiB/sub 2/ and TiC on Poco graphite substrates have been selected and tested as limiters in ISX. Both limiter materials gave clean, stable, reproducible tokamak discharges the first day of operation. After one weeks exposure, the TiC limiter showed only superficial damage with no coating failure. The TiB/sub 2/ limiter had some small areas of coating failure. TiC coated graphite limiters have also been briefly tested in the tokamaks Alcator and PDX with favorable results

Mechanical properties of chemical vapor deposited coatings for fusion reactor application

Chemical vapor deposited coatings of TiB/sub 2/, TiC and boron on graphite substrates are being developed for application as limiter materials in magnetic confinement fusion reactors. In this application severe thermal shock conditions exist and to do effective thermo-mechanical modelling of the material response it is necessary to acquire elastic moduli, fracture strength and strain to fracture data for the coatings. Four point flexure tests have been conducted from room temperature to 2000/sup 0/C on TiB/sub 2/ and boron coated graphite with coatings in tension and compression and the mechanical properties extracted from the load-deflection data. In addition, stress relaxation tests from 500 to 1150/sup 0/C were performed on TiB/sub 2/ and TiC coated graphite beams to assess the low levels of plastic deformation which occur in these coatings. Significant differences have been observed between the effective mechanical properties of the coatings and literature values of the bulk properties