Contexto y recursos necesarios

An overview of the chapters within this thesis is outlined below, the aim of this

being to provide a brief summary of the chapters and how they relate to both the

objectives discussed previously and the development of the thesis overall.

A review of the literature available involving rotor-stator devices in the formation of

emulsions is presented in Chapter 2. Specifically, the review covers droplet break-

up, emulsion stabilisation and the analysis of small droplets in an emulsion using a

laser particle sizer. As well as an overview of these subject areas, Chapter 2 also

discusses the impact of scaling up of rotor-stator mixers. From the published work

analysed, a set of conclusions have been drawn. It is clear from these conclusions,

that similar work must be undertaken for the new rotor-stator technology as there is

disagreement on the scale-up principle; it has not yet been proved that the equations

already available for predicting the impact of rotor-stator mixers apply to all

available rotor-stators if they are of a different design. Further to this, the literature

analysed showing work in similar areas with rotor-stator mixers involves formulation

of emulsions with a low phase volume of oil (none greater than 50%); with the

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aims of this research was to prove that the mixer was capable of processing viscous

fluids and emulsions made with a high phase volume of oil (60–70% were observed).

Work was undertaken using standard, readily available processing equipment to

establish the impact of formulation parameters in creating an emulsion with the

smallest droplet size. Chapter 3 details the mixers used within each experiment of the

research work undertaken and presented in this thesis, at ever increasing volumes.

Bench-top mixers of varying dimensions and the impact they had on the subsequent

reaction is discussed and reviewed in Chapter 6, a feasibility study.

The target aim of Chapter 4 was to produce an emulsion with the smallest droplet

size and ascertain the parameters required to do so whilst ensuring that they are

repeatable. A Formax high-throughput formulation platform and design of

experiment (DoE) software was used to map both the process and formulation

parameters and the impact altering them has on the size of the droplets within the

emulsion produced. Prior to the work in Chapter 4 being published, there was no fast

and efficient way of mapping out the impact that altering the formulation parameters

has on the size of the droplets. The model system chosen consisted of silicone oil,

water and SLES (Sodium Lauryl Ether Sulfate) surfactant. Chapter 4 discusses an

investigation into the formulation parameters required to make an emulsion with the

smallest droplet size. The research work in Chapter 4 was published in the Journal of

Dispersion Science and Technology (Harvey et al., 2013).

Following the work in Chapter 4, the formulation parameters identified that created

an emulsion with the smallest drop size were used to discover the size of the droplets

in an emulsion produced using the UMPF. Chapter 5 presents the results of trials

7 parameters had the greatest impact on the size of the droplets in the final product.

This work allowed an evaluation of the Controllable Deformation Dynamic Mixing

(CDDM) technology using a standard emulsion system.

Using the formulation parameters that were discovered in Chapter 4 to produce an

emulsion with the smallest droplet size, a series of trials were performed using both a

Silverson in-line rotor-stator mixer and the UMPF allowing the CDDM technology

to be benchmarked against a commercially available Silverson in-line rotor-stator

mixer. Chapter 5 identifies key points about the novel design of the UMPF and

presents the possibility of using high-throughput formulation mapping for future

pilot-plant scale production.

Chapter 6 presents the outcome of a series of trials designed to establish a proof of

principle that smaller reagent droplet sizes [through emulsification] decrease the

reaction time of a simple biphasic reaction. The simplest reaction chosen to perform

the feasibility study was saponification. The work displayed in Chapter 6 shows that

using a high-throughput synthesis platform, the point at which the reaction reaches

completion can be identified to a time with an error of a couple of minutes.

The final piece of work performed and reported within this thesis involves

ascertaining whether a biphasic reaction system hindered by the presence of water

can be improved upon by emulsifying one of the reagents. An investigation in

Chapter 8 is reported which details the feasibility of forming biodiesel using a

submicron emulsion of plant [sunflower] oil and methanol, despite methanol being

miscible in water. Feasibility trials were performed prior to the creation of large

batches of emulsion and large scale reactions. The impact of emulsifying the reagent

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reaction, with samples taken at time points to monitor the reactions progress to

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