Optimization of Preparation of Activated Carbon from Ricinus communis Leaves by Microwave-Assisted Zinc Chloride Chemical Activation: Competitive Adsorption of Ni²⁺ Ions from Aqueous Solution

Table 2

Experimental design matrix and results.

Runs	Variables				Responses (Y)
	A	B	C	D	Yield (Y1, %)	Iodine number (Y2, mg/g)
1	1	1	1	1	49.43	735.50
2	2	1	1	1	55.51	898.97
3	3	1	1	1	56.40	980.70
4	4	1	1	1	41.69	940.40
5	1	1	1	1	35.64	1389.30
6	1	2	1	1	48.64	1307.60
7	1	3	1	1	48.57	1552.97
8	1	4	1	1	47.85	13207.6
9	1	1	1	1	45.79	898.40
10	1	1	2	1	46.95	1062.10
11	1	1	3	1	49.90	1144.10
12	1	1	4	1	43.13	1062.10
13	1	1	1	1	49.43	735.50
14	1	1	1	2	52.52	980.67
15	1	1	1	3	58.34	1225.87
16	1	1	1	4	56.18	1144.10