Metallurgical Engineer

PHNX Materials•San Leandro, CA

3d•Onsite

About The Position

PHNX Materials is seeking a Metallurgical Engineer to develop and scale metal extraction processes in a hands-on pilot plant environment. The engineer will work with R&D and process engineering teams to design flowsheets, run experimental campaigns, and address metallurgical problems across hydrometallurgical and pyrometallurgical unit operations. The role involves taking processes from bench results to pilot operation and contributing scale-up recommendations. It reports to the CTO and works closely with R&D, EH&S, vendors, and national lab partners. PHNX Materials is a solids refinery that processes industrial waste, primarily coal ash and zinc slag, into critical metals for semiconductor and defense applications, cement replacement material, and fertilizer. The company describes its mission as strengthening domestic critical mineral supply chains, helping power producers retire coal ash liabilities, and providing a lower-carbon cement alternative.

Requirements

B.S. or M.S. in Metallurgical Engineering, Chemical Engineering, Materials Science, Mineral Processing, Geochemistry, or a related field.
Strong understanding of hydrometallurgical principles, including leaching, solvent extraction, and precipitation, along with mineral processing fundamentals.
Ability to translate engineering concepts into practical experimental setups and operating improvements in a pilot plant or industrial environment.
Proficiency in Excel for engineering analysis and mass balance calculations.
Ability to independently plan work, communicate technical findings, and collaborate across disciplines in a fast-moving startup where priorities evolve.
Must be a U.S. national due to obligations around the company's funding.

Nice To Haves

Pyrometallurgical experience.
Experience with design of experiments (DoE) or process modeling software such as Aspen, FactSage, or HSC Chemistry.
Exposure to high-temperature processing such as roasting, calcination, or volatilization and product recovery, through coursework, research, or industry.
Experience developing or scaling processes for critical minerals, industrial byproducts, or unconventional feedstocks.
Experience using ICP, XRF, XRD, or SEM data to inform process development.
Experience with equipment sizing, vendor interaction, techno-economic analysis, or pilot plant commissioning.
Familiarity with hazard assessments, SOPs, and safe handling of hot, corrosive, or toxic materials.
Previous industry, research, or internship experience in mining, metals recovery, chemical processing, or semiconductor manufacturing.

Responsibilities

Plan and execute bench- and pilot-scale campaigns, evaluate equipment performance, and guide operating strategies for hydrometallurgical and pyrometallurgical circuits.
Develop and evaluate metal extraction and separation flowsheets, including equipment selection, operating conditions, and materials of construction for high-temperature and corrosive service.
Design experiments to improve recovery, selectivity, product purity, and reagent efficiency for critical metals from industrial byproduct feedstocks.
Analyze experimental and operating data, develop mass and energy balances, and translate findings into process improvements and scale-up recommendations.
Interpret analytical results from techniques such as ICP, XRD, and XRF to understand feedstock variability, metal distribution, and process performance.
Support equipment specifications, RFQs, and vendor evaluation, and assist with installation and commissioning of pilot equipment.
Investigate process bottlenecks and inconsistent performance, identify root causes, and implement practical engineering solutions.
Incorporate safe operating practices into process design and experimental planning, contribute to hazard assessments, and develop and follow Standard Operating Procedures (SOPs).
Contribute engineering content to technical reports and milestone updates for government-funded programs.