Synthesis of hydroxyethyl cellulose from industrial waste using microwave irradiation

The paper describes the synthesis of hydroxyethyl cellulose from industrial waste, namely, air particle vacuum dust (APVD). The selected reaction parameters were sodium hydroxide concentration, ethylene oxide proportion, reaction time, and reaction temperature in an attempt to understand their effects on the reaction. For this purpose, APVD was bleached and mercerized using sodium hydroxide and hydrogen peroxide solution to remove/dissolve non-cellulosic material. The modified waste material was then reacted with ethylene oxide under microwave irradiation to obtain hydroxyethyl cellulose. To determine the effect of each reaction parameter, the degree of substitution and viscosity were measured and compared in detail. The greatest values were achieved using 40% (w/v) sodium hydroxide, one gram ethylene oxide per gram of APVD, a 90 min reaction time, and a 70 °C reaction temperature. Process efficiency was evaluated by recording 1H-NMR (nuclear magnetic resonance), solid-13C-NMR, Fourier Transform Infrared Spectroscopy, Differential Thermal Analysis-Thermogravimetry, Differential Scanning Calorimetry and Scanning Electron Microscope of best samples. These helped elucidate the expected reaction. The proposed method, compared with the conventional method, was easy, fast, and straightforward. Keywords: Air particle vacuum dust, Synthesis, Microwave, Hydroxyethyl cellulos

Comparison of classic Fenton with ultrasound Fenton processes on industrial textile wastewater

This study provides a comparison between classic and modified (i.e., ultrasound) Fenton process on the industrial textile wastewater. For this purpose, the classic, and ultrasound Fenton process were investigated and compared using the following parameters: pH of solution, amount of ferrous ion (Fe(II)), and hydrogen peroxide as well as reaction time. With these parameters, degrading organic compounds (i.e., decolorization percentage) was calculated. The best decolorization percentage (95% for Pt-Co) was found using 0.10 g L−1 of Fe(II), and 2.20 g L−1 of H2O2 for 90 min at pH 3 for classic Fenton process. Similar experiments were carried out using 35 kHz ultrasonic irradiation, and the best decolorization percentage (99% for Pt-Co) was obtained via 0.05 g L−1 of Fe (II) and 1.65 g L−1 H2O2 for 60 min at pH 3 for ultrasound Fenton process. The results showed that decolorization increased with decreasing amount of chemical for the ultrasound Fenton process. Additionally, the contact time was decreased by comparing performance with classic Fenton process. In light of these results, the ultrasound Fenton process can be used for decolorization of textile wastewater to save reaction time and chemical costs. Also, the decolorized water (e.g., treated water) may be reused in the plant for washing the textile materials after applying ion exchange process