No abstract

No abstract

No abstract

The swelling and cleaning behavior of layers of a non-cross-linked acrylate-styrene copolymer, simulating fouling layers found in emulsion polymerization reactors, in aqueous sodium hydroxide (NaOH), was studied using the novel measurement technique of fluid dynamic gauging. The polymer exhibited swelling, dissolution, and deswelling, depending on temperature and pH in the range 7-13.4. The mechanisms were elucidated using FT-IR spectroscopy and AFM. The swelling profiles exhibited case II diffusion behavior, the rate of swelling being proportional to the change in free volume on swelling. The effect of thickness was also studied using single and double polymer layers; the swelling rate and extent of swelling were independent of the initial thickness only when the films were made of a single layer.

Abstract. Coconut milk manufacturing process encounters problems with foulants formed during pasteurization process. For example, fouling layers reduce heat transfer efficiency of a heat exchanger. As the fouling layers are considered as waste, this research aimed at extracting coconut oil from the foulants to produce a product from the waste. A model coconut milk foulant was used to simulate foulants formed during batch pasteurization process and coconut oil was extracted from the foulant using celloulase enzyme. The extracted oil then was evaluated in terms of fatty acid composition and antioxidant properties (total phenolic and flavonoid contents). The antioxidant activities were evaluated using DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging and FRAP (Ferric reducing antioxidant power) methods. Results showed that the oil extracted from the foulants appeared similar to virgin coconut oil (VCO); the extracted oil appeared as clear viscous liquid with aroma associated with roasted coconut. The oil extracted using enzyme contained all fatty acids found in VCO in lower proportions but large extent of linoleic acid was found. Antioxidant capacity was similar to that of VCO. The foulants after the extraction of fat using enzyme were easier to clean suggesting the possibility to couple cleaning of coconut milk foulants and oil extraction in the same process.