Thermolysis of N,N,N-trimethyl-1-adamantylammonium hydroxide

Economical and Sustainable Synthesis of Small-Pore Chabazite Catalysts for NOx Abatement by Recycling Organic Structure-Directing Agents

“…As shown in Table , the TMAdaOH concentration in the waste liquid after H-SSZ-13-R0 synthesis was determined to be 114.4 g/L, similar to the values by TGA (115.7 g/L) and by mass calculation (114.5 g/L) based on the synthesis experiment. In contrast, the TMAdaOH concentration in the waste liquid after H-SSZ-13-R1 synthesis was found to be only 32.6 g/L, significantly lower than that by TGA (about 91.1 g/L) or by calculation (89.6 g/L), probably due to a destruction of the TMAdaOH structure after two cycles of hydrothermal reaction at 160 °C (12 days in total) . These destroyed parts, while not detectable by the BGC method, were included in the calculation by the TGA method, resulting in an overestimation of residual TMAdaOH in the waste liquid after two hydrothermal cycles.…”

“…In contrast, the TMAdaOH concentration in the waste liquid after H-SSZ-13-R1 synthesis was found to be only 32.6 g/L, significantly lower than that by TGA (about 91.1 g/L) or by calculation (89.6 g/L), probably due to a destruction of the TMAdaOH structure after two cycles of hydrothermal reaction at 160 °C (12 days in total). 43 These destroyed parts, while not detectable by the BGC method, were included in the calculation by the TGA method, resulting in an overestimation of residual TMAdaOH in the waste liquid after two hydrothermal cycles. It is thus no surprise that the quality of the SSZ-13 zeolite (e.g., BET surface area) was not satisfactory without supplementing TMAdaOH into the waste liquid after H-SSZ-13-R1 synthesis (Table S2 and Figure S6).…”