Crystallization of X-type zeolite from concentrated sodium silicate and aluminate solutions

Na–X Zeolite Synthesis Using the Response Surface Methodology Design of an Experimental Method for Atmospheric Water Harvesting

“…Table 1 shows the effective parameters and ranges used in references for the synthetic Na–X zeolite powder. [ 30–39 ]…”

“…Table 1 shows the effective parameters and ranges used in references for the synthetic Na-X zeolite powder. [30][31][32][33][34][35][36][37][38][39] Among the factors affecting the design of the test parameters, three parameters, the SiO 2 /Al 2 O 3 molar ratio, the autoclave temperature, and the final pH of the mixture, were held constant, and the remaining four parameters were selected from the range specified in Table 1. Three levels were selected for four parameters using the L9 test design results in Table 2.…”

“…The range used in references The range used in DOE SiO 2 /Al 2 O 3 2.8-3.5, [35] 3, [33] 3.5, [30] 1.5-4 [36] 3 fixed Na 2 O/Al 2 O 3 3-5.1, [35] 3.5, [34] 4, [30] 5, [33] 10, [31] 13 [32] 3.5,10,13…”

“…Rest time before autoclaving [h] 1, [34,36] 20, [39] 24, [31] 72 [33] 2,24,72 pH of suspension after autoclaving 7, [4,35,38] 8 [37] 7 fixed…”