The Effect of Citric Acid on Physicochemical Properties of Hydrophilic Carboxymethyl Starch-Based Films

The physicochemical properties of organo-silica xerogels derived from organo catalyst were pervasively investigated, including the effect of one-step catalyst (citric acid) and two-step catalyst (acid-base), and also to observe the effect of sol pH of organo-silica xerogel toward the structure and deconvolution characteristic. The organo-silica xerogels were characterized by FTIR, TGA and nitrogen sorption to obtain the physicochemical properties. The silica sol–gel method was applied to processed materials by employing TEOS (tetraethyl orthosilicate) as the main precursor. The final molar ratio of organo-silica was 1:38:x:y:5 (TEOS:ethanol: citric acid: NH3:H2O) where x is citric acid concentration (0.1–10 × 10−2 M) and y is ammonia concentration (0 to 3 × 10−3 M). FTIR spectra shows that the one-step catalyst xerogel using citric acid was handing over the higher Si-O-Si concentration as well as Si-C bonding than the dual catalyst xerogels with the presence of a base catalyst. The results exhibited that the highest relative area ratio of silanol/siloxane were 0.2972 and 0.1262 for organo catalyst loading at pH 6 and 6.5 of organo-silica sols, respectively. On the other hand, the organo-silica matrices in this work showed high surface area 546 m2 g−1 pH 6.5 (0.07 × 10−2 N citric acid) with pore size ~2.9 nm. It is concluded that the xerogels have mesoporous structures, which are effective for further application to separate NaCl in water desalination.

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Vibrational spectra, hydrogen bonding interactions and chemical reactivity analysis of nicotinamide–citric acid cocrystals by an experimental and theoretical approach

New Journal of Chemistry ◽

10.1039/c9nj03085a ◽

2019 ◽

Vol 43 (40) ◽

pp. 15956-15967 ◽

Cited By ~ 1

Author(s):

Priya Verma ◽

Anubha Srivastava ◽

Anuradha Shukla ◽

Poonam Tandon ◽

Manishkumar R. Shimpi

Keyword(s):

Hydrogen Bond ◽

Hydrogen Bonding ◽

Citric Acid ◽

Physicochemical Properties ◽

Vibrational Spectra ◽

Theoretical Approach ◽

Chemical Reactivity ◽

Hydrogen Bond Interactions ◽

Hydrogen Bonding Interactions

The hydrogen bond interactions in the cocrystal lead to spatial arrangements enhancing the physicochemical properties.

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Effect of citric acid on physicochemical properties and protein structure of low‐salt restructured tilapia ( Oreochromis mossambicus ) meat products

Journal of the Science of Food and Agriculture ◽

10.1002/jsfa.10784 ◽

2020 ◽

Author(s):

Zhipeng Gu ◽

Shuhui Liu ◽

Zhouwei Duan ◽

Rui Kang ◽

Meihui Zhao ◽

...

Keyword(s):

Protein Structure ◽

Citric Acid ◽

Physicochemical Properties ◽

Meat Products ◽

Oreochromis Mossambicus ◽

Low Salt

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The Effect of Citric Acid Concentration on the Properties of LaMnO3 as a Catalyst for Hydrocarbon Oxidation

Catalysts ◽

10.3390/catal9030226 ◽

2019 ◽

Vol 9 (3) ◽

pp. 226 ◽

Cited By ~ 9

Author(s):

Zakaria Sihaib ◽

Fabrizio Puleo ◽

Giuseppe Pantaleo ◽

Valeria La Parola ◽

José Luis Valverde ◽

...

Keyword(s):

Citric Acid ◽

Physicochemical Properties ◽

Photoelectron Spectroscopy ◽

Catalytic Performance ◽

Morphological Properties ◽

Molar Ratio ◽

Hydrocarbon Oxidation ◽

Total Oxidation ◽

Propene Oxidation ◽

X Ray

LaMnO3 (LM) catalysts with a molar ratio of citric acid (CA) to metal (La3+ + Mn2+) nitrates ranging from 0.5 to 2 (LM0.5 to LM2) were synthesized by the citrate sol–gel method with the aim of studying the effect of the citric acid ratio on the physicochemical properties and the catalytic performance in hydrocarbon oxidation. Structural and morphological properties of these catalysts were characterized by X-ray diffraction (XRD) and specific surface area (N2 adsorption) measurements, while the chemical composition was determined by inductively coupled plasma atomic emission spectroscopy (ICP-OES). In the selected samples, additional characterizations were carried out by thermogravimetric and differential thermal analysis (TGA/DTA), Fourier Transform Infrared Spectroscopy (FT-IR), temperature-programmed reduction by hydrogen (H2-TPR), and X-ray photoelectron spectroscopy (XPS). The results showed that the amount of citric acid used significantly influenced the TGA/DTA profile of gels along with the physicochemical properties of the catalysts. The XRD patterns are consistent with the perovskite formation as the main phase. The segregation of a small amount of Mn3O4, detected for molar ratios ranging between 0.5 and 1.5, suggested the formation of a slightly nonstoichiometric LaMn1−xO3 phase with a relatively high content of Mn4+. The catalytic performance was evaluated in the total oxidation of two selected hydrocarbons, toluene and propene, which represent typical volatile organic compounds (VOCs). Typically, three consecutive catalytic cycles were performed in order to reach steady-state performance in toluene and propene oxidation. Moreover, the stability of the catalysts under reaction conditions was investigated through 24-h experiments at 17% of toluene conversion. The catalysts LM1.2, LM1.3, and LM1.5 showed the best catalytic performance in both hydrocarbon oxidations, well comparing with the Pd/Al2O3 used as a reference.

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