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<html><head></head><body><h3><strong>About Cocoon</strong></h3>
<p>At Cocoon, we’re building low-carbon construction materials for the builders of tomorrow. Steel and cement together account for nearly 15% of global CO₂ emissions — and we’re tackling that challenge by developing and scaling a low-carbon cement substitute.</p>
<p>We’re an early-stage, fast-growing company moving from pilot trials into demonstration and capital project delivery. This role sits at the heart of that transition, shaping how our process is designed, de-risked, and implemented at scale, and playing a critical role in turning our technology into an operational reality.</p>
<h3>The Role</h3>
<p>We’re looking for a Senior Process Engineer to lead process design, scale-up, and project delivery across Cocoon’s next-generation slag activation system. You’ll work closely with process and mechanical engineers, material scientists, researchers, and technicians to optimise our core process and integrate it with existing steelmaking infrastructure.</p>
<p>This role spans front-end engineering, pilot and lab development, capital project delivery, and commissioning. You’ll take ownership of process design packages, champion process safety, and represent process engineering internally and externally as we scale from pilot to demonstration, and to commercial scale.</p>
<h3>Responsibilities</h3>
<h4>Process Design and Scale-Up</h4>
<ul>
<li>Own and deliver process design packages (PFDs, mass and energy balances, equipment specifications) across front-end engineering, detailed design, and execution phases.</li>
<li>Produce and review process models and calculations, ensuring sound engineering fundamentals underpin all designs.</li>
<li>Plan, execute, and analyse lab and pilot-scale development trials to de-risk process scale-up.</li>
<li>Lead process engineering input across the project lifecycle, from design through installation and commissioning.</li>
<li>Ensure alignment of process design with cost, schedule, operability, and performance targets.</li>
</ul>
<h4>Process Safety, Risk &amp; External Engagement</h4>
<ul>
<li>Lead and support process safety reviews (e.g. HAZID, HAZOP) and proactively manage process risks.</li>
<li>Ensure designs meet internal, regulatory, environmental, and safety requirements.</li>
<li>Represent process engineering in discussions with equipment vendors, consultants, trial partners, and contractors.</li>
<li>Clearly define and manage technical scope and requirements with third parties.</li>
<li>Champion sustainable design, energy efficiency, and continuous improvement in process and equipment selection.</li>
</ul>
<h4>Leadership and Culture</h4>
<ul>
<li>Provide technical leadership and mentorship to engineers and technicians.</li>
<li>Support the development of fellow engineers and contribute to a collaborative, inclusive, knowledge-sharing culture.</li>
<li>Contribute to continuous improvement in design practices, safety performance, and project outcomes.</li>
<li>Support installation, commissioning, and testing activities in the UK and internationally.</li>
</ul>
<h3>You’ll Succeed In This Role If You…</h3>
<ul>
<li>Hold a Master’s degree in Chemical or Process Engineering and have 5+ years of industry experience in process development and scale-up.</li>
<li>Bring a strong technical foundation in process design, modelling, engineering calculations, and process safety.</li>
<li>Are comfortable owning deliverables in lean project teams without heavy functional support.</li>
<li>Thrive in fast-paced, evolving environments and bring a practical, hands-on problem-solving mindset.</li>
<li>Communicate clearly and confidently across technical and non-technical audiences, including vendors and partners.</li>
</ul>
<h4>Bonus qualities</h4>
<ul>
<li>Hands-on experience across the capital project lifecycle, including design, construction, commissioning, and operations.</li>
<li>Experience scaling technologies from lab or pilot to demonstration or full-scale implementation (TRL 4/5 to TRL 8/9).</li>
<li>Familiarity with stage-gate development processes and capital project lifecycles.</li>
<li>Knowledge of minerals processing, solids handling equipment, or industrial water systems.</li>
<li>Background in steelmaking, pyrometallurgy, or high-temperature fluid/refractory systems, including FMEA or structured risk methodologies.</li>
</ul>
<h3>What We Offer</h3>
<ul>
<li>A senior role at the heart of Cocoon’s scale-up and deployment journey.</li>
<li>Direct ownership of process design and safety for first-of-a-kind technology.</li>
<li>Close collaboration with a multidisciplinary, mission-driven team.</li>
<li>Competitive salary, stock options, and strong growth opportunities as we scale.</li>
</ul>
<h3>Apply Now</h3>
<div>If you’re excited about scaling new industrial processes and helping decarbonise the steel and cement industries, we’d love to hear from you.</div></body></html>

Senior Process Engineer

<html><head></head><body><h3><strong>About Cocoon</strong></h3>
<p>At Cocoon, we’re building low-carbon construction materials for the builders of tomorrow. Steel and cement together account for nearly 15% of global CO₂ emissions — and we’re tackling that challenge by developing a low-carbon cement substitute.</p>
<p>We’re an early-stage, fast-growing company tackling hard, first-of-a-kind engineering problems. As we move from pilot trials toward demonstration and scale-up, this role plays a central part in shaping how our technology is designed, deployed, and operated in the real world.</p>
<h3>The Role</h3>
<p>We’re looking for a Process Engineer to support process design, development trials, and early-stage scale-up of Cocoon’s next-generation slag activation system. You’ll work closely with process and mechanical engineers, material scientists, researchers, and technicians across lab, pilot, and plant environments.</p>
<p>This is an early-career, hands-on role with strong exposure to real-world engineering — from preparing design documentation and running development trials, to supporting equipment installation, commissioning, and process safety activities. You’ll build your technical capability while contributing directly to Cocoon’s scale-up journey.</p>
<h3>Responsibilities</h3>
<h4>Process Engineering &amp; Safety</h4>
<ul>
<li>Participate in process hazard reviews and assist in identifying and mitigating process safety risks.</li>
<li>Maintain a safety-first mindset in all engineering activities and promote a proactive safety culture.</li>
<li>Prepare and update engineering documents, including PFDs, P&amp;IDs, mass and energy balances, and equipment specifications.</li>
<li>Support process calculations and design work under guidance from senior engineers.</li>
</ul>
<h4>Development Trials &amp; Scale-Up Support</h4>
<ul>
<li>Organise and run lab and pilot-scale development trials with cross-functional teams.</li>
<li>Gather, analyse, and interpret data to support process understanding and scale-up decisions.</li>
<li>Support design coordination, installation, and commissioning of new equipment and processes.</li>
<li>Build knowledge of standard process engineering deliverables, tools, and methodologies through hands-on work and mentorship.</li>
</ul>
<h4>Coordination &amp; Reporting</h4>
<ul>
<li>Liaise with equipment suppliers, contractors, and internal stakeholders to gather technical data and support procurement and delivery processes.</li>
<li>Support the achievement of project milestones by contributing to technical reports, presentations, and design documentation.</li>
<li>Communicate clearly with engineers, scientists, technicians, and external partners.</li>
<li>Support development trials, installation, and testing activities in the UK and internationally.</li>
</ul>
<h3>You’ll Succeed In This Role If You…</h3>
<ul>
<li>Hold a degree in Chemical or Process Engineering and have up to 3 years of industrial experience (or relevant internships/placements).</li>
<li>Have a solid foundation in core chemical engineering principles, including mass and energy balances, thermodynamics, and transport phenomena.</li>
<li>Are enthusiastic about hands-on engineering and motivated to learn through practical experience.</li>
<li>Are organised, detail-oriented, and willing to take ownership of tasks in a lean team.</li>
<li>Communicate effectively and enjoy collaborating across disciplines and environments.</li>
</ul>
<h4>Bonus qualities</h4>
<ul>
<li>Exposure to lab or pilot plant operations or industrial process environments.</li>
<li>Familiarity with standard engineering documentation (e.g. PFDs, H&amp;MBs, equipment specifications).</li>
<li>Understanding of process safety concepts such as HAZOP or FMEA.</li>
<li>Exposure to pyrometallurgy, refractory systems, high-temperature processes, minerals processing, or solids handling equipment.</li>
<li>Experience with engineering tools or software (e.g. Excel, process simulators, AutoCAD, Visio).</li>
</ul>
<h3>What We Offer</h3>
<ul>
<li>Hands-on exposure to process design, trials, and early-stage scale-up of new technology.</li>
<li>Close mentorship from experienced process and mechanical engineers.</li>
<li>The opportunity to contribute meaningfully to a mission-driven, fast-growing company.</li>
<li>Competitive salary, stock options, and work flexibility where possible.</li>
</ul>
<h3>Apply Now</h3>
<div>If you’re excited to build your process engineering skills while helping decarbonise steel and cement, we’d love to hear from you.</div></body></html>

Process Engineer

<html><head></head><body><h3><strong>About Cocoon</strong></h3>
<p>At Cocoon, we’re developing low-carbon construction materials for the builders of tomorrow. Delivering our technology at demo-plant scale requires extensive hands-on engineering work: building, installing, commissioning, and operating equipment that enables testing and material generation in real-world conditions.</p>
<p>This role is central to delivering and scaling our technology. You’ll drive implementation and delivery for the engineering team, building test rigs, installing equipment at partner sites, and supporting trials in the UK and USA as we scale towards building a permanent plant.</p>
<h3>The Role</h3>
<p>We’re looking for an Engineering Technician to build, install, and operate prototype equipment and test rigs that support Cocoon’s R&amp;D and material generation programmes. You’ll work closely with engineers, scientists, and operations teams to deliver trials safely, on time, and to specification, often in challenging industrial environments.</p>
<p>This is a highly practical, travel-heavy role involving mechanical build, electrical wiring, hydraulics, commissioning, troubleshooting, and trial execution. You’ll spend significant time travelling, supporting test campaigns, and installing equipment at partner locations in the UK, Europe, and the US.</p>
<h3>Responsibilities</h3>
<h4>Test Rigs, Equipment, and Trials</h4>
<ul>
<li>Build test rigs and prototype equipment to agreed designs, timelines, and quality standards.</li>
<li>Install, commission, and operate equipment at Cocoon test sites and partner facilities in the UK and abroad.</li>
<li>Carry out tests under the direction of a test engineer and report findings.</li>
<li>Upgrade and modify test rigs with new hardware, controls, instrumentation, or mechanical components.</li>
<li>Suggest process and hardware improvements and be a key source of information for the R&amp;D and process engineering teams from on the ground running of our system.</li>
<li>Support extended test campaigns in the UK and overseas, including driving 3.5-tonne Luton vans, completing risk assessments, and working outdoors in challenging industrial environments.</li>
</ul>
<h4>Mechanical, Electrical and Workshop Work&nbsp;</h4>
<ul>
<li>Perform mechanical, hydraulic, and pneumatic assembly of prototype equipment.</li>
<li>Wire automation cabinets, sensors, actuators, pumps, and 3-phase systems.</li>
<li>Read and interpret manufacturing drawings, wiring diagrams, and process diagrams.</li>
<li>Carry out light machining and fabrication (cutting, drilling, grinding, welding, bending, pipe joining).</li>
<li>Create components using additive manufacturing techniques.</li>
<li>Order service parts, manage workshop organisation, and support general site readiness.</li>
</ul>
<h3>You’ll Succeed In This Role If You…</h3>
<ul>
<li>Have extensive, hands-on experience as an engineering technician in a related industry.</li>
<li>Are confident with mechanical build, basic electrical installation, hydraulics, and troubleshooting.</li>
<li>Can work independently on targets while collaborating closely with engineers and scientists.</li>
<li>Are proactive, dependable, safety-conscious, and driven to solve problems.</li>
<li>Are willing and able to travel extensively and work extended hours during test campaigns.</li>
</ul>
<h4>Bonus qualities</h4>
<ul>
<li>Knowledge of industrial automation, instrumentation, and PLCs</li>
<li>Welding qualifications, especially TIG for stainless steel</li>
<li>Forklift qualification or experience operating heavy equipment.</li>
<li>Electrical installation or wiring qualifications.</li>
<li>Experience working with foundries or high-temperature process equipment.</li>
</ul>
<h3>What We Offer</h3>
<ul>
<li>A hands-on role at the centre of Cocoon’s engineering and scaling journey.</li>
<li>The opportunity to work on first-of-a-kind test rigs and prototype equipment.</li>
<li>Extensive travel and exposure to world-class industrial partners and test facilities.</li>
<li>Clear progression opportunities toward workshop lead, supervisor, or test engineer roles.</li>
<li>A mission-driven team working to support the transition to Net Zero.</li>
</ul>
<h3>Apply Now</h3>
<div>If you’re excited by building hardware, running trials, and spending time in the field turning engineering designs into reality, we’d love to hear from you.</div></body></html>

Engineering Technician

<html><head></head><body><h3><strong>About Cocoon</strong></h3>
<p>At Cocoon, we’re building low-carbon construction materials for the builders of tomorrow. Steel and cement together account for nearly 15% of global CO₂ emissions — and we’re tackling that head-on by developing the next generation of sustainable, high-performance materials.</p>
<p>We’re an early-stage, fast-growing company with a big mission and a small, hands-on team. Every day brings new challenges and new opportunities to make a real impact on the climate crisis.</p>
<h3>The Role</h3>
<div>We’re looking for a Laboratory Technician to support our researchers, manage day-to-day lab workflow, and operate and maintain a wide range of analytical equipment. You’ll help prepare samples and run characterisation methods, including XRD, PSA, ICP-OES, TGA, and isothermal calorimetry. You’ll be responsible for ensuring the lab remains organised, safe, and fully stocked.</div>
<p>You will also support the installation and commissioning of new sample preparation and analytical capabilities. By keeping equipment operating smoothly and data flowing reliably, you’ll play a central role in enabling Cocoon to accelerate research and development.</p>
<h3>Responsibilities</h3>
<h4>Laboratory Operations</h4>
<ul>
<li>Supporting researchers with their critical workstreams.</li>
<li>Sample preparation for material characterisation.</li>
<li>Conducting material characterisation work in the lab (XRD, PSA, ICP-OES, TGA, isothermal calorimetry).</li>
<li>Ensuring the lab is tidy, inventory is up to date, and consumables are restocked.</li>
<li>Managing QC processes from industrial trials.</li>
<li>Overseeing the installation, troubleshooting, and commissioning of lab equipment.</li>
<li>Operating and maintaining small-scale furnaces and Cocoon’s lab-scale prototype granulators.</li>
</ul>
<h4>Data Management&nbsp;</h4>
<ul>
<li>Developing a pipeline or dashboard for tracking analysis that is visible to the team.</li>
<li>Archiving material characterisation data effectively so all users can access it.</li>
<li>Data generation and cataloguing on Cocoon’s databases.</li>
<li>Generating data to support the commercial activities of the business</li>
</ul>
<h4>You’ll Succeed In This Role If You…</h4>
<ul>
<li>Bring experience in material characterisation from steel, cement, or a related field such as battery technology.</li>
<li>Have previous technician or lab manager experience.</li>
<li>Are comfortable organising large data sets.</li>
<li>Have an eye for detail and follow processes to the letter.</li>
<li>Thrive in a fast-moving, hands-on laboratory environment.</li>
</ul>
<h4>What We Offer</h4>
<ul>
<li>A central role in scaling Cocoon’s laboratory capabilities.</li>
<li>The opportunity to support formal research advancement across the team.</li>
<li>The chance to contribute data directly to demo-plant development and commercial work.</li>
<li>Clear growth pathways, including:
<ul>
<li>Conducting your own research.</li>
<li>Running onsite QC at pilot trials abroad.</li>
<li>Progressing toward Lab Manager and owning all H&amp;S.</li>
</ul>
</li>
<li>A competitive salary, plus 28 days annual leave.</li>
</ul>
<h4>Apply Now</h4>
<div>If you’re excited about generating high-quality data, supporting critical research, and helping Cocoon scale towards demo-plant deployment, we’d love to hear from you.</div></body></html>

Laboratory Technician

<html><head></head><body><h3>About Cocoon</h3>
<p>At Cocoon, we’re developing low-carbon construction materials for the builders of tomorrow. Steel and cement account for nearly 15% of global CO₂ emissions, and decarbonising these industries requires completely new approaches to mix design, testing, and implementation.</p>
<div>We’re now building our in-house concrete capability so we can qualify SCMs, validate performance against industry standards, and support deployment of our technology at pilot and demo-scale. To do this, we’re establishing a fully equipped concrete laboratory in London — and we’re looking for a Concrete Technologist to help make it happen.</div>
<h3>The Role</h3>
<p>We’re looking for a Concrete Technologist to design, mix, test, and manage concrete across an extensive experimental programme. You’ll help establish our concrete lab from the ground up, commission equipment, write SOPs, and deliver mechanical and durability testing to ASTM, BSI, and related standards.</p>
<div>You’ll run the full lifecycle of concrete development — from mix design and batching, through casting and curing, to compressive strength and durability testing — while keeping meticulous data records and maintaining a safe, well-organised laboratory. You’ll also support field trials, coordinate external testing, and contribute technical insights to our research and commercial teams.</div>
<div>This role is hands-on, varied, and central to Cocoon’s ability to qualify SCMs, validate performance, and scale towards real-world deployment.</div>
<h3>Responsibilities</h3>
<h4>Concrete Development &amp; Testing</h4>
<ul>
<li>Develop concrete mix formulations across the experimental matrix (SCM replacement, admixtures, w/b ratios) to ASTM C1709 and BSI Flex 350.</li>
<li>Plan batching schedules, specimen numbers, test timelines, and weekly execution plans.</li>
<li>Optimise mix proportions and troubleshoot workability, flash setting, segregation, and strength issues.</li>
<li>Operate the mixer and conduct fresh property tests (slump, density, air content, bleeding).</li>
<li>Record batch data (temperature, timings, slump, w/b) and maintain full QA/traceability.</li>
<li>Cast cubes and cylinders; manage curing tanks, curing regimes, and specimen conditioning.</li>
<li>Perform compressive and flexural strength testing at 7, 28, and long-term ages.</li>
<li>Prepare and run durability tests (RCPT, bulk resistivity, water absorption, sorptivity, permeability, drying shrinkage, sulfate resistance, carbonation depth).</li>
</ul>
<h4>Laboratory Setup, Management &amp; Safety</h4>
<ul>
<li>Write SOPs for all concrete lab processes and commission existing equipment.</li>
<li>Identify, procure, and install the missing equipment required for the testing regime.</li>
<li>Conduct baselining exercises for cement and industry incumbents.</li>
<li>Maintain calibration, servicing, and safe operation of all equipment.</li>
<li>Manage consumables (PPE, mould oil, aggregates, cement) and keep the lab organised and compliant.</li>
<li>Ensure all risk assessments are in place and adhered to.</li>
</ul>
<h4>Data, Collaboration &amp; External Coordination</h4>
<ul>
<li>Maintain digital logs, record raw data, and align outputs with current data storage methods.</li>
<li>Process and analyse test results; prepare technical reports and summaries, and present data for internal reviews, meetings, and partner updates.</li>
<li>Advise on SCM qualification routes and recommend workflow improvements.</li>
<li>Train team members in SOPs, mixing, fresh testing, and equipment use.</li>
<li>Coordinate outsourcing for tests not done in-house and manage samples, logistics, and external data integration.</li>
<li>Support small-scale field trials and demonstration pours, including onsite testing.</li>
</ul>
<h3>You’ll Succeed In This Role If You…</h3>
<ul>
<li>Have hands-on experience in concrete testing, materials laboratories, or construction materials research.</li>
<li>Are confident working to ASTM, BS EN, and other standards.</li>
<li>Enjoy practical, repetitive experimental work and take pride in process discipline.</li>
<li>Communicate clearly and maintain rigorous documentation.</li>
<li>Thrive in a fast-moving environment with changing priorities.</li>
<li>Are proactive, organised, and comfortable owning a lab space.&nbsp;</li>
</ul>
<h3>What We Offer</h3>
<ul>
<li>A chance to build Cocoon’s concrete lab from the ground up.</li>
<li>The opportunity to generate data that feeds directly into demo-plant development.</li>
<li>Hands-on experience with a wide range of mechanical and durability tests.</li>
<li>Collaboration with researchers, commercial teams, and external laboratories.</li>
<li>Clear growth opportunities as our concrete and materials programmes scale.</li>
<li>A competitive salary and stock options, plus 28 days of annual leave.</li>
</ul>
<h3>Apply Now</h3>
<div>If you’re excited about developing and testing low-carbon concrete — and helping Cocoon scale towards real-world deployment — we’d love to hear from you.</div>
<div>&nbsp;</div></body></html>

Concrete Technologist

<html><head></head><body><h3><strong>About Cocoon</strong></h3>
<p>At Cocoon, we’re building low-carbon construction materials for the builders of tomorrow. Steel and cement together account for nearly 15% of global CO₂ emissions — and we’re tackling that head-on by developing the next generation of sustainable, high-performance materials.<br>We’re an early-stage, fast-growing company with a big mission and a small, hands-on team. Every day brings new challenges and new opportunities to make a real impact on the climate crisis.</p>
<h3>The Role</h3>
<div>We’re looking for a Team and Facilities Assistant to help keep our operations running smoothly — someone who takes pride in keeping things organised, efficient, and well-communicated. You’ll be the first point of contact for many of the day-to-day details that keep our office, lab, and team running safely and effectively.</div>
<div><br>This role suits someone proactive and practical, who enjoys solving small problems before they become big ones, and who’s happy switching between admin, logistics, and people support throughout the day.</div>
<div>&nbsp;</div>
<h3>Responsibilities</h3>
<h4>Team Support</h4>
<ul>
<li>Organise flights, accommodation, and vehicle hire</li>
<li>Arrange couriers, postage, and deliveries</li>
<li>Support training bookings and related logistics</li>
<li>Organise team lunches and socials</li>
</ul>
<h4>Facilities Management&nbsp;</h4>
<ul>
<li>Keep the office running smoothly day to day — an efficient and welcoming space for everyone</li>
<li>Maintain high standards throughout: well-stocked, tidy, and clean.</li>
<li>Ensure the team has what they need, when they need it e.g. PPE, office supplies, stationery, coffee and tea etc.</li>
<li>Take ownership of all health and safety measures, including first aid supplies, fire safety checks, and maintaining relevant training records</li>
<li>Manage relationships with suppliers and contractors — from building maintenance and cleaning to facilities services — ensuring reliability and good value</li>
<li>Oversee office equipment maintenance, keeping everything in excellent working order.</li>
<li>Troubleshoot and resolve any operational issues quickly, keeping things running without disruption.</li>
<li>Act as the main contact for utilities (landlord, electricity, internet)</li>
<li>Manage security and access to our building</li>
</ul>
<h4>Procurement and Bookkeeping</h4>
<ul>
<li>Raise and place orders on behalf of the team, ensuring items are ordered accurately and cost-effectively</li>
<li>Check and process deliveries, arrange returns when necessary</li>
<li>Maintain inventory and reorder consumables</li>
<li>Check and process team expenses to ensure prompt repayment</li>
<li>Set up new supplier accounts and handle credit applications</li>
<li>Support wider finance activities when needed — including reconciliations, income audit, accounts receivable, and month-end processes</li>
</ul>
<h4>You’ll Succeed In This Role If You…</h4>
<ul>
<li>Love organisation and get satisfaction from ticking things off lists</li>
<li>Have a knack for keeping people, places, and processes in sync</li>
<li>Are proactive and happy to chase loose ends without being asked</li>
<li>Communicate clearly and calmly, even when things get busy</li>
<li>Have familiarity with basic bookkeeping or office management tools (e.g. Google Sheets, Xero or similar)</li>
</ul>
<h4>What We Offer</h4>
<ul>
<li>Competitive salary (£28K–£35K pro rata depending on experience)</li>
<li>Flexible working with 20–25 hours per week, spread across 3-5 days</li>
<li>A hands-on role in a growing company tackling one of the biggest challenges of our time</li>
<li>A supportive, collaborative team that values initiative, curiosity, and good humour</li>
</ul>
<h4>How to Apply</h4>
<div>If you’re excited about building the foundations of a net-zero future — and helping the team behind it stay organised and effective — please click Apply below.</div></body></html>

Job Openings

Senior Process Engineer

Process Engineer

Engineering Technician

Laboratory Technician

Concrete Technologist

Team and Facilities Assistant (Flexible working)