Phase equilibrium of volatile organic compounds in polymeric solvents using group contribution methods
- Authors: Muzenda, Edison
- Date: 2010
- Subjects: Volatile organic compounds , Phase equilibrium , Glycol polymers , Biodiesel
- Type: Article
- Identifier: uj:4697 , http://hdl.handle.net/10210/10930
- Description: Group contribution methods such as the UNIFAC are of major interest to researchers and engineers involved synthesis, feasibility studies, design and optimization of separation processes as well as other applications of industrial use. Reliable knowledge of the phase equilibrium behavior is crucial for the prediction of the fate of the chemical in the environment and other applications. The objective of this study was to predict the solubility of selected volatile organic compounds (VOCs) in glycol polymers and biodiesel. Measurements can be expensive and time consuming, hence the need for thermodynamic models. The results obtained in this study for the infinite dilution activity coefficients compare very well those published in literature obtained through measurements. It is suggested that in preliminary design or feasibility studies of absorption systems for the abatement of volatile organic compounds, prediction procedures should be implemented while accurate fluid phase equilibrium data should be obtained from experiment.
- Full Text:
Volatile organic compounds- biodiesel thermodynamic interactions: influence of temperature
- Authors: Ramdharee, Sashay , Muzenda, Edison , Belaid, Mohamed
- Date: 2016
- Subjects: Activity coefficients , Biodiesel , Phase equilibrium , Universal functional activity coefficient
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/93659 , uj:20376 , Citation: Ramdharee, S., Muzenda, E. & Belaid, M. 2016. Volatile organic compounds- biodiesel thermodynamic interactions: influence of temperature.
- Description: Abstract: This work investigated the suitability of biodiesel (predominantly Methyl Linolenate, Methyl Palmitate, Methyl Oleate and Methyl Stearate) as an absorbent for the recovery of VOCs from waste gas process streams through absorption. The objective was to predict the vapour liquid equilibria (VLE) data in the form of infinite dilution activity coefficients for five VOC families, in fatty acid methyl ester solvents at varying temperature. The Original Universal Functional Group Activity Coefficient (UNIFAC) model (Fredenslund et al., 1975) , Modified UNIFAC (Larsen et al., 1981)  and Modified UNIFAC (Bastos et al., 1988)  was used to predict the required phase equilibrium. Alkanes, alcohols and acids/ester interactions showed an increase in activity coefficients with increase in temperature. The influence of temperature on the activity coefficients for alkene and amine families was negligible. The solubility of VOCs in biodiesel decreases with increase in ester hydrocarbon unsaturation. The solubility of VOCs increased with increase in ester molecular weight.
- Full Text: