2.5.2. Water release rate (WRR)
To determine WRR, Shezad et al.’s (2010) method was used with small modifications. The wet BC samples were cut into small pieces and dried using a freeze dryer (MCFD5508, SIM International CO.) for 48 h. The dried BC samples (1 g) were subsequently immersed in distilled water under shaking (100 rpm) condition at room temperature for rewetting. After complete rewetting (stabilized wet weight), samples were analysed for WRR by continuously measuring their weights at various time intervals at room temperature until complete drying. The weights of the BC samples at different time intervals were plotted against time.