Gas Separations and Pyrometallurgical Scale-Up Engineer

PHNX Materials | San Leandro, CA, with travel to commercial site in Montana

Note:

We can only hire U.S. nationals due to obligations around our funding.

China controls 98% of the world's gallium, 92% of germanium, and 93% of silicon. In 2024, China weaponized export restrictions on gallium and germanium, putting the vulnerability on full display. Each of these metals is a byproduct of heavy industry that no longer exists in the United States. We cannot reshore the supply chain because the underlying industries are gone.

PHNX is the answer to closing that gap, sponsored by the U.S. Department of War and the U.S. Department of Energy. We are a solids refinery turning industrial waste, primarily coal ash and zinc slag, into three product streams: critical metals for semiconductors and defense, cement replacement material for construction, and fertilizer for agriculture.

PHNX was founded by Stanford, Tesla, and national lab alumni, backed by Trust Ventures, Overture, and KdT. We are executing a DoW-sponsored Phase II scale‑up program (GALLANT II) for gallium recovery, moving from pilot to commercial scale over the next two and a half years.

You will own the engineering scale‑up of our downstream gas‑phase separations train and the upstream high‑temperature reactor that feeds it. The separations train is where the product slate is made: a mixed product vapor is split into discrete gallium, germanium, and silicon streams via staged condensation, desublimation, and scrubbing. The reactor runs hot and in corrosive gas service. Both have to scale from our current multi‑kilogram pilot to a 100 ton‑per‑day facility over the next two and a half years.

This role exists because the unit operations we need have not been built at commercial scale in the United States in over thirty years. You will design them from primary pilot data.

The chemistry is metallurgical, but the engineering rides on top of universal physical principles: hot acid‑gas service, multi‑component condensation, scrubbing, and recycle loop design. We are explicitly open to candidates from refining, petrochemicals, sulfur recovery, and specialty gas processing whose backgrounds map onto these unit operations, alongside candidates from extractive metallurgy.

This is not a QA, QC, validation, or plant‑operations role. We are not hiring someone to maintain a process. We are hiring someone to design one that does not yet exist.

This is not a desk role. You will be in the pilot bay running campaigns, in the design tools sizing equipment, on calls with vendors specifying alloys and internals, and on site for commissioning.

• Gas‑phase separations train. Design and commission the downstream train that splits a mixed product vapor into discrete gallium, germanium, and silicon streams via staged condensation, desublimation, and scrubbing. Own the thermal profile, vessel internals, materials of construction, sequencing logic, and the close‑cut separations that determine final product purity. This is where the product slate is made.
• Reactor scale‑up. Take our current single‑zone pilot reactor to a multi‑zone commercial system that feeds the separations train  residence time, gas‑solid contacting, freeboard, refractory and alloy selection, and heat integration. Specify and procure the long‑lead reactor itself.
• Hot corrosive gas management. Own the gas stream end to end: reactor offtake, transport lines between unit operations, pressure balance, vent and scrub systems, and the recycle loop that closes the reagent balance at commercial scale. The chemistry generalizes to acid‑gas service across industries, including HCl, SO₂, H₂S, and NH₃ environments. This is the most under‑engineered system in pyrometallurgical scale‑up and the one most likely to determine whether the facility runs.
• Mass and energy balances, P&IDs, and equipment specifications across the full refinery. Support AACE Class 3 cost estimation as we move into the commercial design phase.
• Bench and pilot experiments to close the engineering uncertainties that block scale‑up. Separation efficiency at each stage, fouling and plugging, alloy and refractory…