Sequestration of Hazardous Dyes from Aqueous Solution Using Raw and Modified Agricultural Waste

Table 1

Physicochemical properties of CR dye.

CAS no.	573-58-0
CA index name	1-Naphthalenesulfonic acid, 3,30-[(1,10-biphenyl)-4,40-diylbis (2,1-diazenediyl)] bis [4-amino-, sodium salt (1:2)]
Molecular formula	C32H22N6Na2O6S2
Molecular weight	696.66 gmol^-1
Molecular surface area	557.6 Å^2
Physical form	Brownish-red powder
Solubility	Soluble in water, ethanol; very slightly soluble in acetone; practically insoluble in ether, xylene
Density	0.995 gcm^-3 at 25°C
Dye class	Azo
Melting point	>360°C
pH range	3.0–5.0
Colour	Blue (pH 3.0) to red (pH 5.0)
pKa	4.1; 3.0
Absorption wavelength ()	497 nm; 488 nm