Effect of simultaneous use of microwave and ultrasound irradiation on the sulfuric acid hydrolysis lignin depolymerization was written by Rana, Masud;Nshizirungu, Theoneste;Park, Jeong-Hun. And the article was included in Sustainable Energy & Fuels in 2022.COA of Formula: C9H12O3 The following contents are mentioned in the article:
In this study, the individual and combined effects of microwave (MW) and ultrasound (US) processes on the depolymerization of sulfuric acid hydrolysis lignin (SAHL) were investigated in a hybrid microwave-ultrasound chem. reactor. Results revealed that the combined use of MW and US processes led to better results in terms of high yields of bio-oil and monomer production (43.01 and 6.69 wt%), as compared to the individual use of MW (32.83 and 4.71 wt%) and US (21.60 and 3.58 wt%) processes. The highest yield of bio-oil (63.50 wt%), which contained 13.04 wt% monomers, was achieved under the optimized reaction conditions of 180°C, 80 min, 30% US frequency and a 1,4-dioxane to formic acid ratio of 250 : 50 (volume/volume). Process parameters such as temperature, time and the content of formic acid added to 1,4-dioxane were chosen carefully and optimized using response surface methodol. (RSM). The results of the statistical anal. of variance (ANOVA) showed that the depolymerization temperature and time significantly affected (ρ < 0.05) the yield of bio-oil. In the liquid products, the compounds guaiacol (G1), ethanone, 1-(4-hydroxy-3-methoxyphenyl)-(G3), 2-(4-hydroxy-3-methoxyphenyl)acetaldehyde (G10), 4-Et phenol (H1), 4-Me phenol (H4), and di-Bu phthalate (DBPH) were produced as major monomers. Meanwhile, the GPC results showed that the mol. weight of SAHL (Mw = ∼2156) was significantly reduced to lower mol. weight compounds (Mw = 638). The findings obtained from this study suggest that the applied MW-US-assisted lignin depolymerization process could be a promising alternative to the sep. use of the MW or US process and can pave the way to continue advancing the lignin conversion practices as a renewable and sustainable resource of aromatic chems. Moreover, the proposed method is believed to possess great potential for conversion of a major waste stream from a pulp industry into aromatic chem. production Future work will be directed toward the simultaneous use of MW-US-assisted depolymerization of lignin in a continuous flow process mimicking the optimized conditions obtained under batch MW-US conditions. This study involved multiple reactions and reactants, such as 4-Hydroxy-3-methoxyphenethanol (cas: 2380-78-1COA of Formula: C9H12O3).
4-Hydroxy-3-methoxyphenethanol (cas: 2380-78-1) belongs to ethers. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. Acyl chlorides and acid anhydrides alcoholysis is another way to produce esters. Acyl chlorides and acid anhydrides react with alcohols to produce esters. Anydrous conditions are recommended since both acyl chlorides and acid anhydrides react with water.COA of Formula: C9H12O3
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem