Jiang, Haiyang (2012) Molecular-scale effects of additives on the nucleation, growth and crystal properties of long-chain alkyl methyl-esters. PhD thesis, University of Leeds.
Abstract
Biodiesel is a diesel-related fuel manufactured from vegetable oils, recycled grease, or animal fats. It is technically competitive with, or offers technical advantages when compared to, conventional diesel fuel. However, the freezing and gelling behaviour of many biodiesel formulations are potentially limiting their applications. It is known that the use of additives is an efficient way to improve the cold flow properties of formulated, so it is very important to clarify the mechanism and effect of additives. Molecular cluster modelling work has been explored to study the effect of additives on crystallization temperature, meta-stable zone width and solubility. A new method has been developed for the prediction of crystallisability through the comparison of structural variability of molecular clusters of pure naphthalene, pure biphenyl, and naphthalene in the presence of biphenyl and vice versa. The approach has been validated through the experimental determination of crystallization temperatures and meta-stable zone width. The predicted growth morphologies of methyl stearate have been derived through attachment energy calculations and the resulting surface chemistry of the morphological habit faces characterized. Molecular simulations using grid search methods combined with experimental observed images were used to investigate the solvent-mediated effect on crystal habits of methyl stearate. Tubidometric studies employing a 100ml batch crystallizer operating in a polythermal mode confirmed the change of crystallization temperature and the meta-stable zone width of methyl stearate with or without additives. Related crash-cooling studies enabled the characterization of crystallization kinetics with or without additives through examination of set paints as a function of supersaturation.
Metadata
Awarding institution: | University of Leeds |
---|---|
Academic Units: | The University of Leeds > Faculty of Engineering (Leeds) > School of Chemical and Process Engineering (Leeds) > Institute of Particle Science and Engineering (Leeds) |
Identification Number/EthosID: | uk.bl.ethos.598018 |
Depositing User: | Ethos Import |
Date Deposited: | 23 Sep 2022 12:20 |
Last Modified: | 23 Sep 2022 12:20 |
Download
Final eThesis - complete (pdf)
Filename: 598018.pdf
Description: 598018.pdf
Export
Statistics
You do not need to contact us to get a copy of this thesis. Please use the 'Download' link(s) above to get a copy.
You can contact us about this thesis. If you need to make a general enquiry, please see the Contact us page.