About PHNX Materials:

PHNX Materials refines coal ash waste into critical products. Our proprietary technology extracts titanium, alumina and rare-earth elements from ash while selling the residual feed as a cement substitute (SCM). Our cost-effective, scalable technology delivers a triple win: securing domestic critical mineral supply chains, helping power producers manage coal ash liabilities, and providing concrete companies a cheaper, greener alternative to cement. Founded by Stanford and Tesla alumni, PHNX is on a mission to mine this abundant domestic natural resource. We are looking for builders, thinkers, and doers to help us scale from pilot to production.

Position overview:

Be part of something extraordinary. Seeking a Metallurgical Engineer intern to step into a fast-paced pilot plant environment. You will work shoulder-to-shoulder with our R&D and Process Engineering teams to validate extraction processes, run pilot-scale campaigns, and troubleshoot real-world metallurgical challenges. You will be handling slurries, analyzing data, and helping refine the technology that will revolutionize heavy industry.

Key Responsibilities:

• Pilot Plant Operations: Assist in the operation of bench and pilot-scale equipment, including leaching reactors, filter presses, crushers, and precipitation circuits.

• Process Optimization: Run experiments to optimize recovery rates for Aluminum, Rare Earth Elements (REEs), and Titanium from coal ash feedstocks.

• Data Analysis: Collect, log, and analyze process data (pH, temperature, flow rates, residence time) to support mass balance calculations and scale-up decisions.

• Sample Characterization: Prepare samples for analysis (ICP, XRD, XRF) and interpret results to validate process efficiency.

• Troubleshooting: Identify operational bottlenecks or mechanical issues in the hydrometallurgical circuit and propose practical engineering solutions.

• Safety First: strictly adhere to Standard Operating Procedures (SOPs) regarding chemical handling (acids/bases) and personal protective equipment (PPE).
  

Qualifications:

• Education: Currently pursuing a B.S. or M.S. in Metallurgical Engineering, Chemical Engineering, Materials Science, or Mineral Processing.

• Technical Knowledge: Understanding of metallurgical principles (leaching, solvent extraction, precipitation) and mineral processing basics (comminution, sizing).

• Hands-On Aptitude: Comfortable working in an industrial/lab environment; not afraid to get your hands dirty or use hand tools.

• Data Driven: Proficiency in Excel for data analysis; experience with design of experiments (DoE) or process modeling software (e.g., Aspen, HSC Chemistry) is a plus.

• Soft Skills: Strong communication skills and the ability to thrive in a scrappy, undefined, and high-energy startup atmosphere.
  

Bonus qualifications:

• Experience with analytical equipment (SEM, XRD, PSA).

• Forklift certification or safety training (HAZWOPER).

• Previous internship experience in mining, chemical processing, or semiconductor manufacturing.
  

What We Offer:

• A rare opportunity to design and launch a facility that takes on some of the world’s toughest environmental challenges.

• A fast-paced, mission-driven startup culture where your ideas matter, your work has immediate impact, and your career can grow as quickly as we do.

• The chance to transform heavy industries and be part of a movement rewriting the future of manufacturing and national security.

Note: We only accept U.S. nationals due to obligations around our funding.

PHNX Materials is an Equal Opportunity/Affirmative Action employer. All qualified applicants will receive consideration for employment without regard to sex, gender identity, sexual orientation, race, color, religion, disability, protected Veteran status, age, or any other characteristic protected by applicable law.