Yi Theng Wong, Pau Loke Show*

School of Chemical and Environmental Engineering, Faculty of Engineering ,

University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia

Bio-plastic production in an aqueous two-phase green system

Dean’s Undergraduate Research Scheme (DURS) 2014

Abstract

The research is the study of the recovery of polyhydroxyalkanoates (PHA) from Ralstonia eutropha H16 using aqueous two-phase system (ATPS) composed of co-polymer of EOPO and salt.

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PO

97

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wt/

wt)

(NH4)2SO4 (wt/wt) (a)

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EO

PO

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t/w

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(NH4)2SO4 (wt/wt) (b)

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EO

PO

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(NH4)2SO4 (wt/wt) (c)

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EO

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Na2HPO4 (wt/wt) (d)

Figure 3(a-d) Phase diagram of EOPO copolymer and salt. (a-c) at room temperature, (d) at 40ºc

To obtain phase diagram using co-polymer with molecular weight of 970,2500 and 3900 and salts

To separate PHA produced using aqueous two-phase system To identified the optimum separation by varying Mw of co-polymer,

type of salt, tie-lie length and volume ratio

Scope of Research

Research Findings

Conclusion & Future work

1. Kaul, A., The Phase Diagram, in Aqueous Two-Phase Systems: Methods and Protocols, R. Hatti-Kaul, Editor. 2000, Humana Press. p. 11-21.

2. Show, P.L., et al., Primary recovery of lipase derived from Burkholderia cenocepacia strain ST8 and recycling of phase components in an aqueous two-phase system. Biochemical Engineering Journal, 2012. 60(0): p. 74-80.

References

Methodology

Introduction

Offers simple, easily scalable, energy efficient and mild separation technique for bio-separation

Temperature-induced separating polymer - EOPO

Has a low cloud point - recyclable

High plastic usage level leads to plastic pollution. Replace conventional plastic with bio-plastic Comes out with a economical way of separating bio-plastic produced

Acknowledgement

The author appreciately acknowledge the technical support from supervisor Dr Show Pau Loke, phd student Yoong Kit, Leong and assistance of Zi Bin, Tan in constructing phase diagram of EOPO/disodium hydrogen phosphate.

Plastic which is made from biomass or biodegradable

PHA studied in the experiment are obtained from Ralstonia Eutropha H16 through fermentation of glucose

Bio-based Bio-

degradable PHA

Figure 1 Recycle scheme of EOPO [2]

The optimum condition for recovery of PHA is achieved using ATPS composed of EOPO3900 and ammonium sulphate with 44.6% TLL, volume ratio of 1 which gives a purification factor of 67%. The experiment has to be repeated to improve the reliability of the result.

Disodium hydrogen phosphate can’t dissolve in water under normal room temperature which increases the complexity in constructing phase diagram

The time taken to form two-phase is decrease as molecular weight of co-polymer increases

Cell + PHA

Table 1 Partitioning of PHA in EOPO3900 and ammonium sulphate

PHA mostly accumulates at the top phase of ATPS

TLL VR PF 41.10 1.00 0%

44.00 2.33 22%

44.60 1.00 67% 46.70 1.90 10%