Introduction
Materials and methods
Materials
Capillary rheometry
Centrifugal spinning
Scanning electron microscopy (SEM) analysis
Thermal analysis
X-ray diffraction (XRD) analysis
Dye adsorption study
Results and discussion
Capillary rheometry
Centrifugal spinning of PVP/TA
Spinneret | Fibre diameter (µm) | Rotational speed (r min−1) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
6000 | 7000 | 8000 | 9000 | 10,000 | 11,000 | 12,000 | 13,000 | 14,000 | 15,000 | 16,000 | ||
Coarse |
\( \bar{x} \)
| x | 7.88 | 5.02 | 5.38 | 4.23 | 4.01 | 3.43 | 2.81 | 2.33 | b | x/b |
σ
| x | 6.16 | 3.12 | 4.31 | 3.04 | 3.00 | 2.20 | 1.69 | 1.47 | b | x/b | |
Fine |
\( \bar{x} \)
| x | x | x | x | x | x | 1.83 | 1.43 | 1.52 | 1.46 | b |
σ
| x | x | x | x | x | x | 1.66 | 1.02 | 1.20 | 0.87 | b |
Internal fine structure and thermal analyses of fibres
Adsorbent behaviour of PVP/TA fibres
Initial dyebath concentration, C
o
(mg dm−3) | ||||||
---|---|---|---|---|---|---|
25 | 50 | 100 | 150 | 200 | 300 | |
Dye/fibre parameters | ||||||
Equilibrium concentration C
e
(mg dm−3) | 0.7 | 8.4 | 24.7 | 38.5 | 61.3 | 122.8 |
Dye removal from solution (%) | 97.1 | 83.2 | 75.3 | 74.3 | 70.4 | 59.1 |
Adsorption at equilibrium Qe (mg g−1) | 4.9 | 8.3 | 15.1 | 22.3 | 27.7 | 35.4 |
Dye/activated carbon parameters | ||||||
Equilibrium concentration, C
e
(mg dm−3) | 1.0 | 5.9 | 21.5 | 40.2 | 73.4 | 150.4 |
Dye removal from Solution, (%) | 95.9 | 88.3 | 78.5 | 73.2 | 63.3 | 49.9 |
Adsorption at equilibrium, Qe (mg g−1) | 4.8 | 8.8 | 15.7 | 22.0 | 25.3 | 30.0 |