Chemical changes of phosphorus‐modified ZSM‐5 zeolite in calcining and steaming processes were studied using solid‐state magic angle spinning nuclear magnetic resonance techniques. 1H?→?31P cross‐polarization magic angle spinning and 31P–27Al rotational‐echo double resonance signals of calcined and steamed P‐ZSM‐5 zeolites were measured and analyzed. Results showed that the average distance between phosphorus and hydrogens in phosphorus compounds was increased while the average distance between aluminum and phosphorus was decreased after the steaming process. Aluminum attached to highly condensed phosphates was protected in the zeolite framework during the steaming process.
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