Synthesis Strategy of Hierarchical Alumiosilicates from Low Grade Indonesian Kaolin with Adjusted Activity in Acetalization Reaction

Synthesis strategy of hierarchical aluminosilicates was carried out by varying the starting material, type of a basic solution, and the hydrothermal condition. Aluminosilicate was synthesized using pre-treated low-quality kaolin by three kinds of basic solution, such as sodium hydroxide, sodium fluoride, and tetrapropyl ammonium hydroxide. The hydrothermal condition was carried out by gradual temperature and constant temperature. The desired mole ratio of Si/Al achieved by dealumination or by addition of silica. Products were characterized by X-ray diffraction, FTIR spectrometry, and nitrogen physisorption. Cation exchange was carried out on the product to obtain an acid catalyst. The acidity test of the catalyst was carried out by FTIR-pyridine spectrometry. The catalyst activity test was carried out to the acetalization reaction of 3,4-dimethoxybenzaldehyde with propylene glycol. The results showed that the catalyst synthesized with the basic solution of tetrapropyl ammonium hydroxide had the highest acid site number and the highest conversion of 3,4-dimethoxybenzaldehyde to acetal.

A green approach for the preparation of a surfactant embedded sulfonated carbon catalyst towards glycerol acetalization reactions

A surfactant embedded carbon-based acid catalyst was prepared via simple physical mixing and thermal treatment to establish the relationship between hydrophobicity and acidic site density for efficient glycerol acetalization reaction.

Selective Hierarchical Aluminosilicates for Acetalization Reaction with Propylene Glycol

Hierarchical micro-mesoporous aluminosilicates nanoparticles were synthesized at different of Si/Al ratios and were directly used as a solid acid catalyst for acetalization reaction with propylene glycol. TEM and N2 adsorption analysis of the resulting aluminosilicates revealed the formation of the hierarchical structure occurs on the Si/Al ratio increases the formation of mesoporous within the structure of aluminosilicate. The aluminosilicates exhibit high selectivity towards acetalization reaction in comparison with the homogeneous PTSA. The presence of mesoporous structures is crucial for increased conversion and selectivity of the reaction which presumably due to the improved diffusion of substrate to reach acid sites.

Algerian Acid Activated Clays as Efficient Catalysts for a Green Synthesis of Solketal by Chemoselective Acetalization of Glycerol with Acetone

The production of solketal and conversion of glycerol takes a major importance in the field of the sustainability of the biodiesel industry. The synthesis of (2,2-dimethyl-1,3-dioxolan-4-yl)methanol by the acetalization of glycerol with acetone successfully applied out using various Algerian acid activated clays (maghnia-H+) under autogenous pressure and without solvent. The acid catalyst clays are prepared by an easy technique by activation with the available and low-cost Maghnia clay. The purified Maghnia clay named ALC and the resulting series of acid-activated clays AL1, AL2, AL3, and AL4 are characterized by X-ray Fluorescence (XRF) investigation, N2-adorption/desorption Brunauer–Emmett–Teller (BET) surface area, X-rays Diffraction (XRD), Fourier Transform Infra Red (FT-IR) spectroscopy, SEM microscopy and the cation exchange capacity (CEC) with copper bisethylenediamine complex method, in order to study the effect of activation at the acid and the catalytic behaviour in the acetalization reaction. The results show a high catalytic activity whose that the yield of solketal production interest reached 95 % at a temperature of 40 °C for a reaction time of 48 hours with full selectivity and glycerol conversion reaching up to 89 %. A mechanistic is proposed to explain the chemoselective of solketal production. These results indicate the potential of this Algerian acid activated clays catalysts for the acetalization of glycerol for an environmentally benign process. Copyright © 2018 BCREC Group. All rights reservedReceived: 28th March 2018; Revised: 17th October 2018; Accepted: 30th October 2018; Available online: 25th January 2019; Published regularly: April 2019How to Cite: Alali, K., Lebsir, F., Amri, S., Rahmouni, A., Srasra, E., Besbes, N. (2019). Algerian Acid Activated Clays as Efficient Catalysts for a Green Synthesis of Solketal by Chemoselective Acetalization of Glycerol with Acetone. Bulletin of Chemical Reaction Engineering & Catalysis, 14 (1): 130-141 (doi:10.9767/bcrec.14.1.2445.130-141)Permalink/DOI: https://doi.org/10.9767/bcrec.14.1.2445.130-141

Catalytic Activity of Tungstophosphorous Acid Supported on Mesoporous Silica for Glycerol Acetalisation to Glycerol Formal

For the acetalization reaction between glycerol and formaldehyde two mesoporous catalyst were prepared, characterized and tested. Mesoporous silicas (MCM-41 and HMS) were synthesized and used as supports for the phosphotungstic acid based catalysts. Glycerol was converted to glycerol formal through a solventless acetalization reaction with formaldehyde catalyzed by tungstophosphorous acid supported on two type of mesoporous silica (30PW/MCM41 and 30PW/HMS). The reaction was carried out in a batch reactor, at 120�C, using 2% catalyst. The highest yield ] 98.5% was achieved over mesoporous 30PW/HMS catalyst. Catalyst characterization was performed by determining the textural characteristics, acid strength and by SEM analyses. The catalytic activity of the catalysts was compared, using the same conditions with two comercial acid catalysts : Amberlyst 15 and p-toluen sulphonic acid on polymer support (PTS/polymer).