HW-3-4 Enhancing Resource Efficiency by Synergistic Direct Air Capture and Water Harvesting Systems

About the Project

This PhD is one of a number of projects hosted by the Centre for Doctoral Training in Green Industrial Futures (CDT-GIF). We are offering pioneering research projects that will enable PhD researchers to explore key technologies and solutions that will support UK industry to reach net zero.

Project Description

Developing new technologies to reduce atmospheric CO2 levels is a globally important research challenge. One of the most promising technologies is direct air capture (DAC), which selectively captures CO2 from air for downstream utilisation or storage. DAC systems currently include a process step that uses chemisorbents, such as amine-based materials, to capture CO2. These sorbents are highly selective for CO2, which is important because the concentration of CO2 in the air is around 400 parts per million. However, using chemisorbents for this separation stage presents sustainability challenges, including the need for high energy inputs to regenerate the sorbent during cycling.

This PhD project aims to develop porous materials (physisorbents) that capture water or CO2 from air via physical adsorption. Physisorbents are, in principle, advantageous for DAC systems because they bind CO2 less strongly, which reduces the energy input required for regeneration. However, a key challenge of using physisorbents is the presence of water vapour in the air, which can interfere with CO2 capture. We propose to overcome this by developing an innovative two-step process that combines two separation steps: 1) water harvesting to remove moisture from air, followed by 2) CO2 capture from the resulting dry air. By this combined strategy, the DAC process can become more resource-efficient, particularly in water-stressed areas. The project will interface with a large project team that includes industrial collaborators to develop innovative machine learning methods to accelerate the discovery of physisorbents (Nature, 2024, 632, 89).

The project is at the interface of chemistry and chemical engineering. It will involve synthesis and testing, focusing initially on metal-organic frameworks, which have tunable pore structures that can be optimised for specific applications, including CO2 capture. However, there is scope to expand to other material classes such as covalent organic frameworks.

Supervisors

• John Andresen / cdtgreenindustrialfutures@hw.ac.uk
• Marc Little
• Susana Garcia

Application Criteria

As a minimum we require candidates to have a First-class or 2:1 MEng or and MSc with merit (over 60%) in a relevant area i.e. Chemical Engineering, Process Engineering, Chemistry, Materials Science, Geoscience etc. Candidates for socio-politico-economic research topics will also be considered with a relevant MA. Applicants who have a First-class BSc/BEng (Hons) and can demonstrate significant relevant industry/research experience may also be considered.

Candidates should be aware of and meet the entry requirements for the university hosting the PhD studentship.

The PhD would be ideal for an applicant with a background in chemistry or chemical engineering who is interested in porous materials and data-driven approaches and would like to develop skills in machine learning. Other related materials science backgrounds will also be considered.

We invite applicants from all backgrounds, genders, and identities who are excited to be part of our supportive and inclusive research environment. Female applicants are particularly invited to apply.

The position will be supervised by a multidisciplinary team with a strong track record in relevant research areas. Dr Marc Little is a materials chemist with expertise in the design, synthesis, and characterisation of porous materials. His research focuses on using automation to accelerate the development of porous materials from discovery to testing and scale-up. Prof Susana Garcia is a chemical and process engineer. Her research focuses on designing novel materials and processes to efficiently mitigate carbon emissions in different power and industrial sectors and remove CO2 from the atmosphere. Her team has changed the paradigm for designing novel processes based on advanced materials by integrating process engineering and basic science. The applicant will benefit from training and development in these areas, including testing through access to world-class facilities in the Research Centre for Carbon Solutions at Heriot-Watt University (https://rccs.hw.ac.uk/). Prior experience in these areas is desirable.

You will receive training in data collection and interpretation, as well as in developing machine learning models. Experience in coding is beneficial but not necessary, as the required training will be provided. You will have opportunities to attend and present at national and international conferences, and undertake a placement, enhancing your communication skills and expertise working with other scientists from academia and industry. Tailored mentoring and support will be provided.

Funding Notes

The programme is four years and starts in September 2026. Funding includes full UK fees, tax-free stipend (2025/2026 stipend is £20,780), plus budget for travel and consumables.

Enquiries

cdtgreenindustrialfutures@hw.ac.uk