Phosphotungstic acid samples supported on nano γ-Al₂O₃ with the loading of (0.5–40  wt/wt%) were prepared by impregnation and calcined at different temperatures for 3 h. The catalysts were characterized by thermogravimetry, differential thermal analysis, X-ray diffraction and N₂ sorption measurements. The acidity of the catalysts was investigated by the dehydration of isopropanol, chemisorption of pyridine and 2,6-dimethyl pyridine. The gas-phase dehydration of ethanol was carried out at 190 °C in a conventional fixed-bed flow type reactor at 1 atm using N₂ as a carrier gas. All catalysts calcined at 500 °C exhibited high selectivity toward diethyl ether (DEE) formation. Moreover, the catalyst of 20% phosphotungstic acid supported on γ-Al₂O₃, AlW20, showed the best selectivity (99%) with 74% yield of DEE. The catalytic performance of supported catalysts were correlated with the strong and intermediate …

Sugar beet roots are becoming a growing source of sugar production. It provides about 40% of world sugar production. In most beet-growing areas, harvest periods are short, and storage is necessary. Deterioration of sugar beet roots leads to an increase in reducing sugar percentage and polysaccharide levels causing a decrease in sucrose content this results in a decline in physical and technological characteristics. This work was carried out in Delta Sugar Company, Kafr Elsheikh governorate, Egypt during the 2022/2023 harvest season. To reduce the deterioration of sugar beet roots after harvesting and before processing. Roots were divided into seven groups. The first one was (a control sample) and the other six groups were treated with different concentrations of sodium metabisulfite (Na2S2O5) from 100 to 600 mg/L (wet weight) for four days in the open air. During this work, we revealed that by adding a concentration of 500 mg/L of sodium metabisulfite we obtained high sucrose content, beet quality, sugar recovery, and pH and we revealed that by addition of 500 mg/L of sodium metabisulfite, we obtained the lowest difference between apparent sugar and true sucrose, the lowest amount of Na, K, and α-amino-N, the lowest percentage of sucrose loss and amount of raffinose content. At 600 mg/L of sodium metabisulfite, it will cause deterioration again because it is an acidic material that leads to increased sucrose inversion again. So, this research aims to preserve the quality of beet and prevent its deterioration by using sodium metabisulfite.

Nowadays, water pollution is considered one of the most global unwanted environmental problems, so its treatment is of great importance. In this study, Corncobs, which are considered agrocellulosic wastes, were used as highly efficient and low-cost sorbents for the adsorptive removal of some 4,6-dimethyl-2-(aryldiazenyl) thieno [2,3-b] pyridine-3(2H)-one dyes from aqueous solutions. The influences of the different operating parameters such as solution pH, sorbent dose, dye concentration, particle size, and contact time are extensively examined. From the experimental results, we found that the adsorption capacity attained its highest value at pH 12 and particle size 0.125 mm, also the adsorption reached equilibrium after 90 minutes. Results revealed that the adsorption data is well described by Langmuir and Freundlich isotherms with higher values of maximum adsorption capacities. It was found that the kinetic model for Ia, Ic and Id are consistent with a pseudo-second-order (R2 >0.99) and Ib is consistent with a pseudo–first-order (R2 >0.99). Therefore, kinetic studies demonstrated that the adsorption process is well fitted by pseudosecond-order model and ruled by pore diffusion and film diffusion mechanism.