Table 2 Analysis of variance (ANOVA) for CCD modeling and process optimization results.

Total

21

9.7665e + 04

4.6507e + 03

Constant

1

8.9274e + 04

8.9274e + 04

Total corrected

20

8.3912e + 03

4.1956e + 02

2.0483e + 01

Model

14

8.3702e + 03

5.9787e + 02

1.7046e + 02

1.3101e−06

2.4451e + 01

Residual

6

2.1044e + 01

3.5074e + 00

1.8728e + 00

Lack of Fit

2

4.4166e + 00

2.2083e + 00

5.3122e−01

6.2431e−01

1.4860e + 00

Pure error

4

1.6628e + 01

4.1570e + 00

2.0389e + 00

Q²

0.949

A–P

46.9730

R²

0.997

RSD

1.873

R² adj

0.992

Predicted R²

0.9486

pH

2.7639E + 03

2.7639E + 03

7.8802E + 02

< 0.0001

74.349

Ads. dose

1.3494E + 02

1.3494E + 02

3.8470E + 01

8.0000E−04

16.4282

Time

2.3371E + 02

2.3371E + 02

6.6630E + 01

2.0000E−04

15.2875

AZT Conc

5.2904E + 02

5.2904E + 02

1.5084E + 02

< 0.0001

− 32.5281

pH*Ads. dose

3.4674E + 02

3.4674E + 02

9.8860E + 01

< 0.0001

− 74.4833

pH*Time

9.8000E + 00

9.8000E + 00

2.7900E + 00

1.4570E−01

− 8.8535

pH*AZT Conc

9.2730E−01

9.2730E−01

2.6440E−01

6.2550E−01

3.85191

Ads. dose*Time

1.7700E + 01

1.7700E + 01

5.0500E + 00

6.5800E−02

11.9001

Ads. dose*AZT Conc

7.0550E + 01

7.0550E + 01

2.0120E + 01

4.2000E−03

− 33.5981

Time*AZT Conc

4.0360E + 01

4.0360E + 01

1.1510E + 01

1.4600E−02

− 17.9681

pH ²

2.0894E + 02

2.0894E + 02

5.9570E + 01

2.0000E−04

− 23.0822

Ads. dose ²

1.7034E + 02

1.7034E + 02

4.8560E + 01

4.0000E−04

− 20.8412

Time ²

1.1244E + 02

1.1244E + 02

3.2060E + 01

1.3000E−03

− 16.9331

AZT Conc.²

1.0520E + 02

1.0520E + 02

2.9990E + 01

1.5000E−03

− 16.3786

pH

7.992

*

–

64.0637

4%

0.996

Ads. dose

0.279

g/L

20.1934

Time

64.256

min

–

1.20639

AZT Conc

10.107

mg/L

–

14.5365

Efficiency

98.362

%

± 3.24

100

Repeat (n = 5)

96.021

%

± 4.23

*