Principal Engineer, Extractive Metallurgy

Redwood Materials Inc.; San Francisco (CA); On-site; USD 180,000 - 280,000; Full time

Job summary

Redwood Materials in San Francisco, CA, seeks a Principal Engineer, Extractive Metallurgy, to lead metallurgical design and deployment across recycling and refining operations. The role drives innovation through bench-to-plant scale-up, owning flowsheets, process development, and product specification, while collaborating with the CTO and CEO to accelerate commercial deployment.

The successful candidate will bring 15+ years in pyrometallurgy or hydrometallurgy, hands-on plant experience, and a

Qualifications

• Advanced degree in a relevant metallurgical field.
• 15+ years experience in extractive metallurgy or minerals processing.
• Proven ownership of flowsheet deployment from pilot to commercial.
• Experience with pyrometallurgy or hydrometallurgy.

Responsibilities

• Serve as senior technical authority on extractive metallurgy for recycling and refining.
• Evaluate flowsheet options and translate data into commercial recommendations.
• Define product quality specs and diagnose impurity deportment.
• Direct mineral processing and mechanical separation strategy.
• Guide scale-up from bench to pilot to commercial operation.
• Collaborate with Business Development to define process pathways and feedstock pricing.
• Mentor teams to improve metallurgical rigor across engineering.

Skills

Metallurgical expertise

Pyrometallurgy & hydrometallurgy

Scale-up from pilot to commercial

Plant operations experience

Technical leadership

Education

Bachelor's or higher in Metallurgical Engineering or related

15+ years experience in extractive metallurgy

Job description

Principal Engineer, Extractive Metallurgy

About Redwood Materials

Redwood Materials was founded in 2017 by JB Straubel, co-founder and former CTO of Tesla, on a simple but radical idea: the critical minerals powering the energy transition already exist. They just need to come back. Today Redwood is the largest lithium-ion battery recycler in North America — recovering, refining, and redeploying critical minerals from end-of-life batteries back into the supply chain. On the energy side, Redwood has deployed the largest second-life battery project in the world, delivering power to AI data centers in months rather than years using proprietary energy architecture engineered entirely in-house. The company is profitable, the market it operates in is projected to grow 20 to 50 times over the next decade, and Redwood is the only company with the supply chain, the technology, and the operational scale to lead it.

Position Summary:

The position serves as Redwood's senior technical authority on extractive metallurgy across the company's recycling and refining operations. The role owns the metallurgical basis of design for how Redwood liberates, separates, and refines metals from recycled feedstocks, spanning mechanical separation of heterogeneous feeds, high-temperature processing, hydrometallurgical refining, and electrochemical upgrading of battery metals and other critical minerals. The position exercises independent judgment on methods and evaluation criteria for first-of-a-kind processes where data is incomplete, and its recommendations determine which flowsheets Redwood deploys at commercial scale. This is a strategic individual contributor role with regular interaction with Redwood's CTO and CEO, and success depends on driving innovation and plant deployment at an exceptional pace.

Essential Duties and Responsibilities

• Serves as Redwood's senior technical authority on extractive metallurgy, owning the metallurgical basis of design for recycling and refining flowsheets from feedstock through refined product
• Leads evaluation and selection of competing flowsheet options, translating bench and pilot data into defensible recommendations for commercial deployment
• Owns the metallurgical basis for intermediate and final product quality specifications, diagnosing impurity deportment across unit operations and driving issues to root cause
• Directs strategy for mineral processing and mechanical separation of heterogeneous feedstocks, including comminution, liberation, classification, and physical concentration
• Guides scale-up from bench through pilot to commercial operation, including mass and energy balances, equipment selection, and vendor test campaigns
• Partners with Business Development to define process pathways and pricing for new feedstocks and to identify offtake markets and their value drivers
• Advises operations and process engineering teams on recovery, yield, and reliability shortfalls at commissioned plants, and raises metallurgical rigor across the engineering organization through technical review and mentorship

Skills, Knowledge, and Abilities

• Bachelor's or advanced degree in Metallurgical Engineering, Extractive Metallurgy, Mining Engineering, Mineral Processing, Materials Science, Chemical Engineering, or a related discipline
• 15+ years of experience in extractive metallurgy, mineral processing, or metals process engineering, or equivalent depth of expertise
• Demonstrated ownership of deploying a flowsheet from pilot scale through commercial operation, with accountability for the plant's technical performance
• Deep industrial-scale experience in pyrometallurgy or hydrometallurgy; experience across both preferred
• Hands-on experience in an operating plant environment such as a smelter, refinery, or concentrator, with ability to travel to plant sites as required
• Experience with comminution and physical separation of variable, heterogeneous feedstocks

The position is full-time. Compensation will be commensurate with experience.

We collect personal information (PI) from you in connection with your application for employment with Redwood Materials, including the following categories of PI: identifiers, personal records, professional or employment information, and inferences drawn from your PI. We collect your PI for our purposes, including performing services and operations related to your potential employment. If you have additional privacy-related questions, please contact us at [e-mail].

Voluntary Self-Identification

For government reporting purposes, we ask candidates to respond to the below self-identification survey.Completion of the form is entirely voluntary. Whatever your decision, it will not be considered in the hiringprocess or thereafter. Any information that you do provide will be recorded and maintained in aconfidential file.

As set forth in Redwood Materials’s Equal Employment Opportunity policy,we do not discriminate on the basis of any protected group status under any applicable law.

If you believe you belong to any of the categories of protected veterans listed below, please indicate by making the appropriate selection.As a government contractor subject to the Vietnam Era Veterans Readjustment Assistance Act (VEVRAA), we request this information in order to measurethe effectiveness of the outreach and positive recruitment efforts we undertake pursuant to VEVRAA. Classification of protected categoriesis as follows:

A "disabled veteran" is one of the following: a veteran of the U.S. military, ground, naval or air service who is entitled to compensation (or who but for the receipt of military retired pay would be entitled to compensation) under laws administered by the Secretary of Veterans Affairs; or a person who was discharged or released from active duty because of a service‑connected disability.

A "recently separated veteran" means any veteran during the three-year period beginning on the date of such veteran's discharge or release from active duty in the U.S. military, ground, naval, or air service.

An "active duty wartime or campaign badge veteran" means a veteran who served on active duty in the U.S. military, ground, naval or air service during a war, or in a campaign or expedition for which a campaign badge has been authorized under the laws administered by the Department of Defense.

An "Armed forces service medal veteran" means a veteran who, while serving on active duty in the U.S. military, ground, naval or air service, participated in a United States military operation for which an Armed Forces service medal was awarded pursuant to Executive Order 12985.