Sharif Digital Repository

Glycerin (glycerol) is a co-product of biodiesel production that is widely produced and is available at a low cost. To date, various applications have been investigated and introduced for biodiesel glycerin. In this study, a number of valuable products were produced using biodiesel glycerin and formic acid as the main reactants. Allyl alcohol is one of the valuable chemicals produced from glycerin monoformate. Efficient production of this product requires successful completion of the first section of the reaction, which is an equilibrium reaction. The highest feasible yield achieved was about 83% (based on the consumption of formic acid) at 120-140°C without the addition of any catalysts.... 

Glycerin (glycerol) is a co-product of biodiesel production that is widely produced and is available at a low cost. To date, various applications have been investigated and introduced for biodiesel glycerin. In this study, a number of valuable products were produced using biodiesel glycerin and formic acid as the main reactants. Allyl alcohol is one of the valuable chemicals produced from glycerin monoformate. Efficient production of this product requires successful completion of the first section of the reaction, which is an equilibrium reaction. The highest feasible yield achieved was about 83% (based on the consumption of formic acid) at 120-140°C without the addition of any catalysts.... 

A novel mesoporous silica-functionalized dual Brønsted acidic species has been introduced as an efficient catalyst for solvent-free esterification of fatty acids with ethanol. The structure of the catalyst has been characterized by FT-IR spectroscopy, thermal gravimetric analysis (TGA), TEM and N2 adsorption-desorption. TGA of catalyst 1 showed no weight loss before 200 °C, indicating a high degree of hydrophobicity of the surface of the mesoporous silica. TEM images and nitrogen adsorption-desorption showed no noticeable changes to the structure of the catalyst before and after acid treatment. pH metric analysis was performed for the catalyst to determine the loading of the acidic sites.... 

12-tungstophosphoric acid, polyoxometalate with Keggin structure, and γ-Al2O3 were synthesized. Loading of 12-tungstophosphoric acid (HPW) on γ-Al2O3 was performed by the post-impregnation method. The catalysts were characterized by XRD, SEM, FTIR, BET, and DRS techniques. According to the pertinent observation, using the post-impregnation method promises the stability of polyoxometalate Keggin structure after loading on γ-Al2O3 support. The stability of 20 %HPW/Al2O3 was also confirmed by a leaching test. Textural characterization demonstrates that HPW on the γ-Al2O3 had a much larger surface area as compared with the pure HPW. The 20 %HPW/Al2O3 exhibited roughly high activity toward an... 

The silanization of nanodiamond (ND) was successfully carried out by using the esterification reaction of hydrolyzed vinyltrimethoxysilane (VTS) in alcoholic solution. The surface carboxylic group of ND was first enhanced by thermal oxidation to increase the degree of esterification reaction. The extent of silane functionalization of ND was controlled by varying the weight ratio of VTS and oxidized ND (oxND), from 2:1 to 10:1 (w/w) in the functionalization reaction medium. Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) revealed that the highest degree of silanization occurred at VTS/oxND of 5:1 (w/w), while more silane concentrations resulted in...