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ICUFA, WBPCB/GCECT/UNSW

Kolkata 10 – 11 January 2013

Near Whitened Fly Ash : UTILIZATION OF AS RECEIVED AND UNSW -

DEVELOPED NEAR WHITENED FLY ASH IN VIRGIN WHITE POLYMER POLYPROPYLENE

Sri Bandyopadhyay, A Zaeni, U P Singh

UNSW SMSE & CIPET LARPM Thanks Prof Binoy K Dutta,

Prof S Maitra, Dr G Ghosh & Team

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Fly ash

• Fine powder

• collected as residue

• in the exhaust gases

• from combustion chambers

• of the pulverized coal fired boilers • at power plant stations

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The fly ash morphology, Spherical also irregular

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Fly ash

Agriculture Cement / Concrete

Polymer composites

Polyester Polyethylene

Polypropylene Epoxy

Other Polymer

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AIMS : Utilization of FA • in Composite based Product with Enriched

Mechanical Properties

New Exp. Conditions Screening

of PolymersModification

of FA

Addition of Additive

Strategies

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So far the reasons of producing polymer composites using fly ash

are :- stiffen the matrix - make it rigid, - lower cost of material, - modify rheological properties, - increase strength properties of polymer

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• Zaeni, Bandyopadhyay et al (1) focussed particle size and distribution, surface morphology, chemical composition, plus colour measurement of several Australian fly ash samples. Further, Zaeni, Bandyopadhyay et al recently developed a method to modify the colour of fly ash from grey black to almost near white (NHFA), to 96 % of the whiteness of calcium carbonate (2). It is believed this will assist the fly ash recycling industry to make better decisions re use of fly ash so far as the colour effect of fly ash products is concerned (see fig 1).

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Normal v Near- Whitened Fly ash

• Bottom 100 % PP tensile sample - white in colour; Middle: As received fly ash / PP, dark green in colour;

Top: Near whitened fly ash / PP; almost white in colour;

Fly Ash P.P.Composites

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0

2

4

6

8

10

0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50%

Volume fraction of filler

Modulu

s (G

Pa)

Smallwood

Guth

Kerner

T63-RT

Furukawa Upper

Furukawa lower

Series model rule of mixture

Parallel model rule of mixture

Mechanical Properties of as received Fly Ash PP Composites

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We developed method :Grey black to almost white, within 5 % of calciulm carbonate

Average Particle Size 8.3 microns Akhmad Zaeni / Sri Bandyopadhyay

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• Our research past 4 years found new use of fly ash as a filler in plastics replacing natural fillers;

• Selective fly ash - modified to

• Near white color – opens up big new applications opportunities

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Australian Provisional Patent 2009

• In March 2009, a standard Australian Patent "

• A Method for Improving the Colour of Fly Ash" was filed

• Application number is 2009200846

• See next slide for the demonstration of this color change.

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UNSW – CIPET India Fly ash PP Project May 2010 [ Sri Bandy & S K Nayak ]

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White fly ash in weight % 5 to 50 with polypropylene

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Results Notched Impact strength vs Fly Ash wt %

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PP Only

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PP Only

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Scanning electron microscope (SEM) fracture surface of PP – 20

wt % Whitened fly Ash notched impact specimen Mechanism of toughening :

Particle debonding and frictional pull-out energies

PP – 20% near-whitened fly ash High magnification

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PP – 50 % NHFA, High magnification

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Bright and white products

• We can use Whitened Fly Ash in very broad areas of engineering, environment, and research.

• We can revolutionize the use for India and Australia

• Thanks West Bengal Government• Thanks WB Pollution Control Board

Conclusion

• Fly ash can be used as an additive in polymers to as high as 50 % by weight if not more.

• Both as-received fly ash and near-whitened fly ash can have beneficial effects in tensile modulus and notched impact properties.

• Scanning electron microscopy of notched impact fracture surfaces show smaller size fly ash particles are embedded in the interlamellar textural matrix of the polymer.

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Acknowledgement

• One part of this presentation is based on a paper by Sri Bandyopadhyay, & Akhmad Zaeni & Dilip Nath et al “Advanced utilization of as received and near whitened fly ash in polypropylene polymer to improve mechanical, notched impact and whiteness colour properties”, International Journal of Plastics Technology, 14, 2010, Supplement 1, 51-56,

• DOI: 10.1007/s12588-010-0011-5. The other part (NHFA-PP Impact studies) of the paper is based on a CIPET Faculty Research collaboration program held at UNSW in 2010, approved by CIPET DG Prof Dr Sanjay K Nayak.

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ThanksWBPCB and GCECT

• Thanks Akhmad at UNSW, Thanks Upinder and CIPET DG Prof Sanjay Nayak

• Thanks my HoS, Dean and DVC-Research at UNSW