Removal of emulsified oil by ethyl cellulose-coated kapok fiber

Quek, Check Shyong

Removal of emulsified oil by ethyl cellulose-coated kapok fiber

dc.contributor.author	Quek, Check Shyong
dc.date.accessioned	2023-11-19T02:33:24Z
dc.date.available	2023-11-19T02:33:24Z
dc.date.issued	2022
dc.description	Thesis (PhD. (Chemical Engineering))
dc.description.abstract	Previous studies have shown effectiveness of kapok fiber and its modified counterpart in absorbing oil but none has involved a stable emulsion that is much more difficult to absorb due to the microscopic size and inability of the oil droplets to float to the surface. Therefore, this study was mainly aimed at investigating all aspects related to the sorption of surfactant-stabilised emulsified oil by raw kapok fiber, and then evaluating its performance against the ethyl cellulose-coated one. Stirring method was employed to submerge the highly buoyant kapok fiber to maximise the interaction between oil droplets and kapok fiber. In this study, the physicochemical characteristics of kapok fiber were investigated using Brunauer-Emmett-Teller, scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, contact angle and elemental analysis. The oil droplet size distribution at different temperatures was analyzed using a Coulter counter, and its relationship with sorption was investigated. Preliminary experiments using normal floating oil and the stirring method showed that the kapok fiber was able to sorb more than 200 times its weight in oil. For emulsified oil, the effects of surfactant, kapok fiber length, stirring speed, pH, sorbate amount, dosage, contact time and temperature on the sorption performance were studied using the one factor at a time method. Then, 5 parameters were chosen for optimization of the sorption process which were pH, sorbate amount, dosage, contact time and temperature, with amounts of oil and water sorbed as responses, using Design Expert 6.0 software. The results also indicated that the sorption of emulsified oil by kapok fiber was spontaneous, endothermic and agreed with the pseudo-first order reaction kinetics. The sorption isotherm agreed with the Freundlich model that was also supported by the BET model, confirming that the adsorption mechanism involved is physisorption. However, the overall sorption mechanism was mainly absorption judging from the low positive value of ΔH° from the thermodynamics. The amount of oil that could be absorbed was about 28.5%, while that of water was less than 0.5% of the original amount (500 mL). Modification of kapok fiber using ethyl cellulose as coating has made it a superhydrophobic rough- surfaced material, from 138.6° to 150.0° for the contact angle. The amount of oil that could be absorbed by the best-performing coated kapok fiber was 36.0% which was a significant improvement over the original raw kapok fiber. Indeed, kapok is a promising natural hydrophobic fiber for the absorption of emulsified oil from oily wastewater where its performance could be enhanced through modification.
dc.description.sponsorship	Faculty of Engineering - School of Chemical & Energy Engineering
dc.identifier.uri	http://openscience.utm.my/handle/123456789/828
dc.language.iso	en
dc.publisher	Universiti Teknologi Malaysia
dc.subject	Emulsions—chemistry
dc.subject	Sorbents
dc.subject	Kapok
dc.title	Removal of emulsified oil by ethyl cellulose-coated kapok fiber
dc.type	Thesis
dc.type	Dataset