Fig. 1From: Optimization of Cr (VI) removal from aqueous solution with activated carbon derived from Eichhornia crassipes under response surface methodologyThe different stages of AC preparation A–D. Where ‘A’ indicates the raw Erichornia crassipes, ‘B’ indicates the dried Erichornia crassipes, ‘C’ indicates the crushed Erichornia crassipes, and ‘D’ indicates the final product (AC)Back to article page