This listing does not state pay. Across 168 open senior listings that state pay, the middle half runs $180,000 to $254,000 and the median is $214,000.

Listed pay is what employers advertise, not what people are paid.

Senior salaries by state · Check your own pay

How AI is used in this kind of work

AI use among chemical engineers is little observed so far. Measured exposure for chemical engineers: 0% (little observed).

Share of this job’s tasks that AI is already used for at work, from real usage. It is not a forecast of job loss, and a low number means no use seen yet. Source: Anthropic Economic Index.

Check how this applies to your own job

Skills this job asks for

Say which you have and which you want to build. We use it to match you to jobs like this one.

About the job

About Mariana Minerals

Mariana Minerals is a software-first, vertically integrated minerals company on a mission to supply the critical minerals powering modern energy, AI, and defense technologies. We’re reimagining the minerals supply chain by combining deep industry expertise with advanced software, automation, and data-driven decision-making.

Role Overview

Mariana Minerals is looking for a highly motivated Sr./Staff Process Engineer to work on building the critical minerals supply chain to support the world’s energy transition and to supply metals necessary for technology and AI, energy, mobility, and defense.

As a Sr./Staff Process Engineer at Mariana Minerals, you will lead the development and deployment of state-of-the-art chemical refining processes, while also supporting development of software for capital project execution and automated plant optimization. Responsibilities will include leading process area and equipment scopes from concept through to design, installation, commissioning, ramp, and handover to the operations team.

What You’ll Bring

Lead process area and equipment scopes from concept and modeling validation, through procurement, engineering, fabrication, installation, commissioning, and ramp

Manage external equipment providers, technology licensors, and engineering companies to deliver fully integrated and functional mineral refining scopes.

Build heat and material balances for integrated mineral refineries

Develop Process Flow Diagrams (PFDs) and Piping & Instrumentation Diagrams (P&IDs) for mineral refineries

Build first-principles-based models of chemical reactors and unit operations to validate and scale-up designs

Identify, evaluate, and implement engineering solutions to optimize process designs, confirming functionality and performance under various operating conditions

Work closely with cross-functional teams including lab technicians, pilot plant engineers, process engineers, project execution teams, and more to scale designs from lab through to commercial scale

Work closely with the software and machine learning teams to automate capital project execution workflows and develop equipment and plant optimization algorithms

What You’ll Bring

Strong understanding of engineering fundamentals and demonstrated ability to leverage this understanding to solve challenging problems

Strong foundation in chemical engineering, metallurgical engineering, or process engineering, with demonstrated ability to apply engineering fundamentals to complex systems

Experience with plant & equipment engineering and design. Including but not limited to:

Brownfield modifications and upgrades

Greenfield design

Evaluation and optimization of operating facilities

Experience with the following industries and/or production environments:

Industrial manufacturing

Large-scale mining or mineral processing, particularly across hydrometallurgy, electrometallurgy, and pyrometallurgy

Large-scale chemical production processes

Engineering, procurement, and construction (EPC/EPCM) firms

Our culture is built on four principles:

Everyone Gets Home Safe. We never put speed or cost ahead of people.

Extreme Ownership. We take full responsibility for outcomes, relentlessly driving toward solutions.

Engineer Out Requirements, then Automate. We simplify, optimize, and then automate for scale.

Share Your Legos. We collaborate openly, share knowledge, and empower each other to build bigger, better solutions.

Join us as we build the future of responsible mineral sourcing and supply!