From sustainable cultures of Cyclotella striata diatoms to crystalline aluminosilicate reactors: a structural insight
Rindia M. Putri,* [a] Novi Syahra Almunadya,[a] Amila Laelalugina,[a] Nadia Tuada Afnan,[a] Grandprix T.M. Kadja, [b,c,d] Rino R. Mukti,[b,d] Didin Mujahidin,[e] Yanti Rachmayanti,[a] and Zeily Nurachman* [a]

[a] Dr. R. M. Putri, N. S. Almunadya, A. Laelalugina, N. T. Afnan, Dr. Y. Rachmayanti, and Prof. Dr. Z. Nurachman
Biochemistry Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha No. 10, Bandung 40132, Indonesia
E-mail: rindia.m.putri[at]itb.ac.id- zeily[at]itb.ac.id
[b] Dr. G. T. M. Kadja and Dr. rer. nat. R. R. Mukti
Division of Inorganic and Physical Chemistry, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha No. 10, Bandung
40132, Indonesia
[c] Dr. G. T. M. Kadja
Center for Catalysis and Reaction Engineering, Institut Teknologi Bandung, Jl. Ganesha No. 10, Bandung 40132, Indonesia
[d] Dr. G. T. M. Kadja and Dr. rer. nat. R. R. Mukti
Research Center for Nanosciences and Nanotechnology, Institut Teknologi Bandung, Jl. Ganesha No.10, Bandung 40132, Indonesia
[e] Dr. D. Mujahidin
Organic Chemistry Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha No. 10, Bandung 40132, Indonesia

Abstract

Diatoms have emerged as a sustainable source of silica with unique structures and distinct pores. Compared to fossilized diatomites, diatoms live cultures can be grown continuously in a controlled manner, to result in a monodisperse and organized biosilica. Herein, we report the cultivation of a tropical marine diatom, Cyclotella striata, to produce amorphous biosilica with a large surface area filled by hierarchical pores. Via chemical incorporation of aluminium atoms into the Si-O-Si network, the micrometer sized biosilica was reassembled into smaller aluminosilicates with intergrowth structures, as corroborated by HR-TEM, SEM-EDX, and FTIR analyses. Furthermore, SAED and XRD revealed that the aluminosilicates displayed crystalline characteristics. The crystals were then employed as reactors to catalyze an etherification between ethanol and tertbutanol, to result in ethyl tert-butyl ether (i.e., an octane enhancer). Our findings demonstrate how sustainably grown diatom cultures can be structurally transformed into crystalline catalysts for the synthesis of high-value products

Keywords: Microalgae, Diatom, Acid Catalyst, ETBE,

Topic: Bioteknologi