HIGH PRESSURE REACTOR FOR SUPERCRITICAL AMMONIA

摘要

A high-pressure cylindrical reactor suitable for a high-pressure process using supercritical ammonia to form bulk crystals of group III nitride or transition metal nitride is disclosed. In one instance, the reactor has a reactor body and lid formed of precipitation hardenable Ni—Cr superalloy and is sealed by a gasket made of Ni-based metal. Ni content of the gasket is greater than Ni content of both the reactor body and lid. The gasket is tapered so that its thickest part is at or near the gasket's inner radius or circumference, and the thinnest part of the gasket is more than 0.2 inch thick and is at or near the gasket's outer radius or circumference. The gasket's surfaces are compressed at 60,000 psi or higher. This construction provides a consistent seal of the reactor for repeated use.

主权项

1. A cylindrical high-pressure reactor for a process using supercritical ammonia comprising
(a) a main body having an annular cross-section and made of precipitation hardenable Ni—Cr based superalloy, having its longest dimension along the vertical direction, its inner diameter larger than 2 inches, its minimum outer diameter larger than 4 inches, and its minimum wall thickness larger than 1 inch; (b) at least one lid on an end of the main body; (c) a gasket to seal the lid to the main body, wherein the gasket has an annular cross-section with an inner radius and an outer radius, and the gasket comprises a Ni-based metal with a Ni content greater than a Ni content of the body's precipitation hardenable Ni—Cr based superalloy; (d) the gasket's Ni-based metal has an ultimate tensile strength between 50 and 100 ksi at room temperature; and (e) a first major surface of the gasket tapers so that the gasket has a thicker portion at the inner radius and a thinner portion toward the outer radius, and wherein the gasket when positioned horizontally has a first taper forming an angle to a horizontal plane of about 10 to about 23 degrees.