Adsorption of Pyruvic and Succinic Acid by Amine-Functionalized SBA-15 for the Purification of Succinic Acid from Fermentation Broth

Abstract

In this study, mesoporous silica SBA-15 was functionalized with primary, secondary, and tertiary aminofunctional silanes onto the channel walls using a postsynthesis method as a first attempt to purify succinic acid from a fermentation broth. Ordered mesostructures of pristine and functionalized SBA-15 were evaluated using small-angle X-ray scattering (SAXS), transmission electron microscopy (TEM), and N 2 adsorption/ desorption isotherms. 13 C and 29 Si magic-angle spinning (MAS) nuclear magnetic resonance (NMR) with 1 H cross-polarization (CP-MAS) and thermogravimetric analysis (TGA) revealed that amino-functional silanes were covalently bound to the active layer of pore walls. The distribution and accessibility of amine groups were characterized by scanning transmission electron microscopy (STEM), elemental analysis, and conductivity measurements. Adsorption isotherms were analyzed using the Sips model, simultaneously obtaining the temperature dependence of isotherms derived from the isosteric heats of adsorption. Pyruvic acid had higher adsorption capacities than succinic acid on amine-functionalized SBA-15, resulting in the selective adsorption of pyruvic acid from binary acid solution. In particular, SBA-15 functionalized with primary amino silane obtained higher selectivity on pyruvic acid compared to that of other amine-functionalized SBA-15. The adsorption capacities of pyruvic acid at equilibrium are dependent on the basicity and distribution of amino silanes. The isosteric heats between 10 and 100 kJ/mol and desorption energy between 1 and 10 kJ/mol revealed that the adsorption of pyruvic and succinic acid originated from the formation of an acid-amine complex via hydrogen bonding. It is proposed that the amine functionalization of ordered mesoporous solids provides a simple and effective method of separating or purifying useful carboxylic acids.

Recovery of succinic acid from fermentation broth

“…Most of the studies published so far on reactive extraction were performed with pure aqueous phases and the organic acid apart from the study of Jun et al (2007). Jun et al claimed that for an efficient reactive extraction of succinic acid with tertiary amines the pH of the fermentation broth should be far below pKa 1 = 4.2 so that most of the acid molecules are in the undissociated form.…”

“…A new approach was published by Jun et al (2007). They suggested the use of mesoporous silica (SBA-15) functionalized with primary, secondary and tertiary amino-functional silanes for the isolation of pyruvic and succinic acid from fermentation broth.…”

“…Pyruvic acid was adsorbed threefold better than succinic acid. Therefore, amino-functionalized SBA-15 silica seems to be more useful for the removal of contaminant acids from fermentation broth than for the separation of succinic acid itself (Jun et al 2007).…”

Adsorptive removal of dihydrogenphosphate ion from aqueous solutions using mono, di- and tri-ammonium-functionalized SBA-15

“…Among all these organic functional groups, several investigations were dedicated to surface modification of different mesoporous silicas using aminoalkoxysilanes for their application in catalysis [2,[6][7][8] as well as environmental pollution control [9][10][11][12][13][14][15][16]. In this regard, different amino-functional groups including mono-, di-and tri-amines proved to be potent adsorbents for heavy metal cations such as mercury, lead, cobalt, copper and zinc cations from water [9,[17][18][19], organic molecules [20,21] as well as CO 2 from gaseous emissions [22][23][24]. Furthermore, protonated amino-functionalized mesoporous silicas were applied for the adsorptive removal of different pollutant anions from water such as chromate, arsenate and selenate [11,[25][26], as well as nutrient anions, namely nitrate and phosphate [27][28][29].…”

Highly-controlled grafting of mono and dicationic 4,4′-bipyridine derivatives on SBA-15 for potential application as adsorbent of CuCl2 from ethanol solution

“…Surface modifications with organic functionalities such as C-C multiple bonds, thiols, sulfonic and carboxylic acids, and amines have been widely used, and allow, for example, localized reactions to be carried out on stable solid inorganic matrices [19][20][21][22][23]. Among several different functional groups reported in the literature, there is considerable interest in the use of 4,4 0 -bipyridine derivatives to modify the surface of mesoporous silicas because of their interesting and well-known electron acceptor, charge transfer and fluorescence properties [24][25][26].…”