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8.1. Principal Chemical Process Engineer-Separation

Phoenix Tailings

Phoenix Tailings

Other Engineering
Burlington, MA, USA
Posted on Nov 1, 2025
About Phoenix Tailings
Phoenix Tailings is a rapidly growing clean mining and metals production startup dedicated to sustainable and economic critical metals production. Our mission is to be the world's first fully clean mining and metals production company, producing the resources needed for the next generation of our economy.
Why Phoenix Tailings
At Phoenix, we believe that nothing great is ever accomplished alone or without the passion of people who push and motivate one another. If you are someone who shares our relentless pursuit of a better future, passion for innovation, and are excited about working with some of the top innovators in the world, then this is the place for you.
Our Values
You are only crazy if you are wrong, it’s ok to be wrong
Lead with Compassion
Be Resourceful
Listen
Hustle
Who We Are Looking For
Phoenix Tailings is looking for a Principal Chemical Process Engineer who brings deep technical expertise in solvent extraction, especially as applied to the separation of rare earth elements. This role is pivotal in advancing our mission to build the foundational infrastructure for a clean, domestic supply of critical materials. You will lead the design, development, optimization and scale-up of solvent extraction processes, directly shaping our technology and creating a greener, more resilient critical metals supply chain.

Key Responsibilities:

  • Lead the development and optimization of solvent extraction circuits for rare earth element separation from both primary and secondary sources
  • Design and execute bench- and pilot-scale experiments to evaluate separation efficiency, reagent performance, and system dynamics
  • Translate laboratory-scale successes into scalable, industrial processes with a focus on safety, sustainability, and cost-effectiveness
  • Own and evolve process flow diagrams (PFDs), mass balances, and P&IDs for solvent extraction systems
  • Drive selection and specification of extractants, diluents, and equipment (e.g., mixer-settlers, columns, or centrifugal contactors)
  • Analyze separation performance data to identify improvement opportunities and implement process changes
  • Collaborate closely with metallurgy, chemical engineering, and operations teams to support plant commissioning and troubleshooting
  • Author technical reports, scale-up plans, and design documentation to support commercialization of Phoenix Tailings’ extraction technologies
  • Stay at the forefront of solvent extraction technologies and rare earth processing trends to inform and elevate process strategy

Qualifications:

  • Ph.D. or M.S. in Chemical Engineering, Metallurgical Engineering, or related discipline with 8+ years of relevant experience
  • Proven expertise in rare earth element/critical metals separation via solvent extraction, including reagent chemistry, process configuration, and optimization
  • Hands-on experience with lab-scale and pilot-scale solvent extraction systems, including safety and operational best practices
  • Deep understanding of phase equilibria, thermodynamics, and kinetics relevant to solvent extraction
  • Demonstrated success in scaling up chemical separation processes from bench to pilot to commercial scale
  • Proficiency with process modeling tools (e.g., Aspen, METSIM, or similar)
  • Excellent problem-solving skills with a passion for experimental validation and continuous improvement
  • Strong written and verbal communication skills, especially in cross-disciplinary environments

We offer a competitive compensation package that is based on expertise. We also offer the following benefits:

  • Healthcare, we care about you and your family: 100% Medical, dental, and vision coverage
  • Stock: Ownership in a fast-growing venture-backed company.
  • Family Focus: Parental leave and flexibility for families.
  • Time Off: Flexible vacation policy to encourage people to get out and see the world.
  • Team Fun: Regularly scheduled events, and celebrations.
  • Learning: Learning and development Opportunities to grow your skills and career.
  • Great team: Working with fun, hard-working, kind people committed to making a difference!
  • Flexible culture: We are results-focused. We don’t work at the office every day.
At Phoenix Tailings, we have an open culture that values learning, and we are looking to grow the team with enthusiastic individuals who share our vision of sustainable mining.
Phoenix Tailings, Inc. is an Equal Opportunity Employer, and we value diversity at all levels. All qualified candidates will receive consideration for employment without regard to race, color, religion, sex (including gender identity, sexual orientation, and pregnancy), national origin, age, disability or genetic information, or any other applicable protected characteristics, and these characteristics will not be a factor for consideration of any work-related decisions (including but not limited to hiring, firing, compensation, and discipline).