Table 2.

The experimental design matrix suggested by the central composite design (CCD) with the corresponding response results of the hydrochar yield (wt %).

Std	Run	Factor (A)	Factor (B)	Factor (C)	Factor (D)	Response (Yield%)
24	1	220	20	1	1:5	40.1
5	2	180	60	2	1:15	55.1
10	3	220	20	1	1:5	39.55
21	4	180	40	3	1:5	55.5
8	5	180	40	3	1:5	55.43
14	6	220	20	3	1:5	40.56
15	7	200	40	1	1:15	44.63
16	8	220	60	1	1:5	38.2
13	9	200	20	2	1:5	45.74
18	10	200	40	3	1:15	45.5
17	11	200	40	2	1:5	45.12
12	12	180	20	1	1:10	56.7
3	13	180	60	1	1:5	54.8
11	14	220	40	2	1:10	38.9
19	15	200	20	3	1:10	46.86
1	16	220	60	3	1:5	38.56
6	17	220	20	1	1:15	39.98
7	18	180	20	3	1:15	57.89
9	19	220	60	3	1:15	38.12
25	20	180	60	2	1:15	54.93
22	21	200	20	2	1:5	46.73
23	22	220	20	1	1:15	40.21
4	23	200	60	3	1:10	42.6
2	24	220	60	1	1:15	37.95
20	25	220	20	3	1:15	40.45