The dissolution kinetics of industrial brine sludge wastes from a chlor-alkali industry as a sorbent for wet flue gas desulfurization (FGD)

Figures & data

Figure 1. Schematic drawing of the experimental setup: (1) heating plate, (2) pH electrode, (3) reaction vessel with a stirrer containing IBSW, (4) pH controller, (5) peristaltic pump, (6) electronic balance, (7) HCl acid solution beaker, (8) plastic tubing, (9) cable, (10) computer.

Table 1. Dissolution rate constants and their correlations coefficients of IBSW.

	Surface chemical reaction		Product layer diffusion
	1 – (1 – X)^1/3 = Krt		1 – 3(1 – X)^2/3+2(1 – X) = Kdt
Process variables	Kr (min)^−1	R^2	Kd (min)^−1	R^2
Temperature (°C)
30	0.0023	0.7108	0.00067	0.9357
50	0.0027	0.7002	0.00091	0.9388
70	0.0025	0.6965	0.00078	0.9367
90	0.0031	0.7896	0.00120	0.9708
Solid-to-liquid ratio (g/mL)
0.5 g/100 mL	0.0053	0.7870	0.0033	0.9552
1 g/100 mL	0.0023	0.7271	0.0023	0.9307
1.5 g/100 mL	0.0034	0.6840	0.0014	0.9513
2 g/100 mL	0.0017	0.7303	0.0007	0.9435
Concentration (M)
0.05	0.0017	0.6625	0.00039	0.9137
0.075	0.0023	0.7126	0.00065	0.9503
0.1	0.0026	0.7002	0.00091	0.9388
0.15	0.0029	0.6951	0.00108	0.9284
Particle size
45–63 µm	0.0034	0.7303	0.001045	0.9513
63–75 µm	0.0030	0.6889	0.001141	0.9202
75–150 µm	0.0027	0.7026	0.000905	0.9386
150–300 µm	0.0023	0.7195	0.000752	0.9435
Stirring speed (rpm)
100	0.0023	0.6923	0.00065	0.9258
200	0.0027	0.6967	0.00091	0.9388
300	0.0029	0.6613	0.00115	0.9092
400	0.0035	0.7414	0.00150	0.9586

Figure 2. Conversion versus time and variation of with reaction time for process variable stirring speed (a, b), solid to liquid ratio (c, d), acid concentration (e, f), particle size (g, h), and temperature (i, j).

Figure 3. The Arrhenius plot for the dissolution of the industrial brine sludge waste.

Figure 4. XRD diffraction patterns for (a) raw industrial brine sludge waste, (b) after 30 min of dissolution, and (c) after 60 min of dissolution. C, calcium carbonate; M, mullite; P, portlandite.

Figure 5. SEM images of IBSW (a) before dissolution and (b) at dissolution (60 min).