###### Abstract  
The possibility of transforming a diatomic-rich waste from the brewing industry into synthetic zeolites has been investigated. After precalcination at 550 \({}^{\circ}\)C to eliminate the retained organic matter, the clean diatomite (Dt; with a Si/Al molar ratio of 17.4), was hydrothermally treated for 24 h with continuous stirring in a 3M NaOH solution at 80 \({}^{\circ}\)C. The results of mineralogical characterization by X-ray diffraction with Rietveld refinement have shown a crystallization of 55% of zeolite P, which was neformed from the amorphous phase, opal-CT and quartz of the starting sample. The spectra obtained by Fourier Transform Infrared Spectrometry have corroborated such zeolitization. N\({}_{2}\) adsorption-desorption isotherms have shown that the zeolitized material (Dt-Z) is mesoporous, with almost 60% more specific surface area than Dt (62.6 m\({}^{2}\)/g vs. 39.4 m\({}^{2}\)/g), greater microporosity and 40% smaller average pore size than Dt (71 A vs. 118 A). This study is a first approximation to know the potential of diatomic wastes as zeolite precursors, for which additional research including an aluminum source will be required. e 2022 2022 2022 2022 2022 2022 202  
processes, adsorbent of cations and organic molecules, desalination processes, gas separation, etc. [4; 5]. There are several publications that cover the study of the synthesis of zeolites from (fundamentally natural) diatomics, some of which are summarized below. [PERSON] et al. [6] manufactured (Fe,Al)-ZSM-5 zeolite microspheres with meso- and macroporosity from natural diatomic, using different reagents (NaOH, tetrapropylammonium bromide (TPABr), NaCl and distilled water). The zeolite was hydrothermally synthesized in an autoclave for 6 days at 180 \({}^{\circ}\)C, with subsequent removal of TPABr by calcination at 550 \({}^{\circ}\)C. Paper sludge ash in combination with different proportions of diatomic as silica source were used by [PERSON] et al. [7] to obtain zeolite Na-P1 (zeolite P). The zeolite crystallization process was carried out by hydrothermal means in an Erlenmeyer flask for 24 h at 90 \({}^{\circ}\)C, using a 3M NaOH solution as alkaline medium. The zeolite obtained presented the capacity to eliminate NH\({}_{4}\)\({}^{+}\) and PO\({}_{4}\)\({}^{3-}\), having potential application in water filtration. [PERSON] et al. [8] produced zeolites with hierarchical porosity from a commercial diatomite. Once several steps were completed, the final zeolitization process was carried out in an autoclave at 150 \({}^{\circ}\)C for 72 h. After applying a scrubbing treatment on a commercial diatomite in order to remove impurity phases, [PERSON] et al. [9] synthesized zeolite P using NaOH, Al(OH)\({}_{3}\) and deionized water as chemical reagents. The zeolitization was carried out by the authors using a water bath at 90 \({}^{\circ}\)C, studying different treatment times (4-24 h). For their part, [PERSON] et al. [10] used a commercial diatomite, NaOH and Al(OH)\({}_{3}\) to synthesize zeolite X. After a first stage of aging at different times and temperatures between 0-120 min and 30-60 \({}^{\circ}\)C, zeolites were obtained by hydrothermal treatment also studying different conditions, between 90-120 \({}^{\circ}\)C and 3-9 h. [PERSON] et al. [11] synthesized mesoporous zeolites using a diatomite exploited in an Iranian mine. The synthesis process covered different stages, including, precalcination; acid treatment; treatment with TPABr, sodium aluminate and NaOH; hydrothermal treatment at 170 \({}^{\circ}\)C for 60 h; treatment with NH\({}_{4}\)NO\({}_{3}\) and final calcination. As a result, the authors obtained ZSM-5 zeolites of good quality. In a relatively recent study, [PERSON] et al. [4] used diatomaceous earth wastes from beer filtration. Apart from distilled water, the diatomite was mixed with NaOH and Al(NO\({}_{3}\))\({}_{3}\)\(\cdot\)9H\({}_{2}\)O as aluminum source.