Research

Forced dynamic oscillations are a key strategy in the Teixeira Lab, where we apply external perturbations (P, T, tau, etc.) to a reacting system to induce synergistic kinetic and transport effects that allow us to access operating regimes never before achievable by static/steady methods.

Imagine a farmer being able to manufacture their own fertilizer by pulling nitrogen from the air and hydrogen from water? The future of chemical manufacturing is in distributed, decentralized reactor systems that leverage local resources in creative but efficient ways to establish robust, sustainable, and equitable access to chemical advances. This inverts our classical centralized manufacturing models and requires intensified systems designed to operate on a small, localized scale. Dynamics is one way that we are doing that.

This work is funded by:

1) NSF CAREER: Nitrogen Activation: Splitting Kinetic Cycles and Breaking Energetic Barriers with Pulsed Catalysis. Link.

2) NSF EFRI DCheM: Precise but Tunable Reactions Through Tunably Precise Surfaces. Link.

Hydrothermal liquefaction uses hot liquid water and catalysts to break down large biopolymers (carbohydrates, lipids, proteins) into low molecular weight biocrudes. Advanced process technologies including continuous flow autothermal reactions, in line extractions and heat integration are all used to find ways of converting carbon-rich waste into valuable fuels and chemicals.

This work is funded by:

1) DOE BETO: A Catalytic Process to Convert Municipal Solid Waste Components to Energy. Link.

2) DOE AMO: Harvesting Energy from Wastewater by Converting Sewage Sludge to Renewable Natural Gas. Link.

3) Massachusetts Clean Energy Center (MassCEC AmplifyMass)

The pharmaceutical sector is undergoing two paradigm shifts in how it considers the development and manufacturing: 1) continuous 'flow chemistry' of small molecule APIs, and 2) the onset of personalized medicine requiring on-demand, custom formulations. Manufacturing has typically scaled from a chemist's flask to a pilot batch reactor up to a scaled-up industrial batch reactor. At each stage, careful consideration must be made to preserve the reaction environment (isothermal, well-mixed, etc.). Safety concerns grow exponentially with volatile/toxic/explosive solvents in large vats. In contrast, the Teixeira lab (and every major pharmaceutical company) is trying to figure out how to translate complex, multistep syntheses into a continuous flow platform that takes raw materials (inputs) and produces highly pure pharmaceuticals (outputs).  

Project: Continuous, dynamic crystallization

We use population balance modeling and custom-built continuous flow microcrystallizers to form monodisperse crystals. Microliter-sized droplets are suspended in tubes where we precisely control the microenvironment (temperature, concentrations, residence times, etc.). 

Project: Workforce development

We work alongside 15 of the world's major pharmaceutical companies through the ACS Green Chemistry Institute's Pharmaceutical Roundtable and AIChE RAPID Institute for Process Intensification to identify key bottlenecks and painpoints in the transition to flow. It turns out, a drastically undertrained workforce is a big one. Translating classical reaction engineering principles (residence time distributions, holdup in multiphase reactors, mixing effects, etc.), our lab has created workforce training modules using advanced techniques such as augmented reality to teach underlying heuristics. 

Project: Diffusional limitations during SPPS

Peptide synthesis occurs in a monomer-by-monomer immobilized growth mechanism. Since Merrifield first established the chemistry (then won the Nobel Prize for it), it's always been done in the same way: amino acid, wash, deprotecting agent, wash, and repeat 10-50 times. The problem is that while you do that, you're growing a polymer into a mesh resin, making it harder for new material to get in and the old material to get out. In this work, originally funded by ACS GCI and now continued with our industrial partner Mytide Therapeutics, we use experimental diffusion methods to characterize these diffusional limitations and strategize how to overcome them. 

Sometimes we actually want to induce a gradient to enhance a rate. In the case of our STTR-funded research, we use CO2 to create a charge gradient in a continuous flow separator. As it dissociates into hydronium (fast) and carbonate (slow), it pulls charged particles out of the water and creates a high purity stream.

We use this logic to understand complex mixtures, too. Using machine learning algorithms, we are able to parse two-component and ten-thousand component mixtures and their phase partitioning behavior.