The utilization of carbonized coffee in purifying zinc dross waste by pyrometallurgy method

Galvanizing industries of Bangladesh produce profuse amount of environmentally hazardous solid waste materials like zinc dross which contains significant amount of valuable zinc and harmful heavy lead. Zinc was extracted as zinc chloride (ZnCl2) from zinc dross. Zinc stearate (ZnSt2) samples were prepared by precipitation method from stearic acid, sodium hydroxide and ZnCl2 by varying the amount of the reagents and product yield found within the range 96.06-99.18%. Characteristic peaks of ZnSt2 were investigated by Fourier Transform Infrared Spectroscopy (FTIR). Differential Scanning Calorimeter (DSC) onset curve assigned accurate melting point within the range 122.84-124.03°C. Surface morphology of ZnSt2 was observed by Scanning Electron Microscope (SEM) and products had semi-crystalline structure. Thermal stability of ZnSt2 was evaluated by Thermo-gravimetric Analyzer (TGA) that complied with literature. A combination of ZnSt2 and Calcium stearate (CaSt2) at 1:1 ratio was used as thermal stabilizer in the powder commercial grade PVC resin and performed better thermal stability. The dehydrochlorination temperature of PVC with mixed stearates was 344.67±1.04°C for 10% (w/w) loading whereas for PVC, PVC with 10% (w/w) ZnSt2 and PVC with 10% (w/w) CaSt2, it was 269.83±1.04°C, 317.33±1.26°C and 323.33±2.08°C respectively.Bangladesh J. Sci. Ind. Res. 51(4), 261-270, 2016

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Dechlorination of a zinc dross

Hydrometallurgy ◽

10.1016/s0304-386x(98)00012-7 ◽

1998 ◽

Vol 49 (1-2) ◽

pp. 179-187 ◽

Cited By ~ 20

Author(s):

N. Güresin ◽

Y.A. Topkaya

Keyword(s):

Zinc Dross

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Characteristics of electrolytic zinc powder produced from zinc dross

Powder Technology ◽

10.1016/0032-5910(79)87042-4 ◽

1979 ◽

Vol 24 (2) ◽

pp. 245-250 ◽

Cited By ~ 10

Author(s):

I.F. Hewaidy ◽

H.O. Sabra ◽

E.H. Nassif

Keyword(s):

Zinc Powder ◽

Electrolytic Zinc ◽

Zinc Dross

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Separation behaviour of zinc dross from hot dip galvanising melts of different aluminium concentrations by alternating magnetic field

Ironmaking & Steelmaking ◽

10.1179/174328108x393812 ◽

2009 ◽

Vol 36 (4) ◽

pp. 316-320 ◽

Cited By ~ 3

Author(s):

A. P. Dong ◽

Shu Da ◽

J. Wang ◽

B. D. Sun ◽

J. G. Shen ◽

...

Keyword(s):

Magnetic Field ◽

Alternating Magnetic Field ◽

Zinc Dross

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Influence of Rare Earth on Hot-Dipped 55%Al-Zn Alloy Coating

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.774-776.1132 ◽

2013 ◽

Vol 774-776 ◽

pp. 1132-1136 ◽

Cited By ~ 6

Author(s):

Tai Xiong Guo ◽

Xue Qiang Dong ◽

Shu Hui Deng ◽

Feng Li ◽

Yi Lin Zhou

Keyword(s):

Corrosion Resistance ◽

Rare Earth ◽

Simulation Experiment ◽

Steel Substrate ◽

Intermetallic Layer ◽

Alloy Coating ◽

Al Alloy ◽

Zinc Dross ◽

Zn Alloy ◽

The Rare Earth

Simulation experiment was done to investigate the effects of rare earth on hot-dipped Zn-55%Al alloy coating. The results show that the rare earth has little effect on the zinc dross and its burning loss is about 10%. The microstructure of coating is similar to that of solidification bath, and which is made up of phases of rich aluminum, rich zinc, rich silicon and rare earth, and intermetallic layer of Al-Zn-Fe-Si. The rare earth phase is needle or rod, and mainly distributed inside rich zinc phase and on the interface between the coating and steel substrate. The rare earth has no obvious influence on coating grain and spangle size. The appropriate addition of rare earth would be helpful to improve the coating bending formability and corrosion resistance.

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