scholarly journals The Bromination of Aromatic Compounds with a Mixture of Peroxyacetic Acid and Bromine in Acetic Acid

1964 ◽  
Vol 37 (7) ◽  
pp. 960-963 ◽  
Author(s):  
Yoshiro Ogata ◽  
Yoshiaki Furuya ◽  
Kenji Okano
Keyword(s):  
Acetic Acid ◽  
Aromatic Compounds ◽  
Peroxyacetic Acid

scholarly journals Self-generated peroxyacetic acid in phosphoric acid plus hydrogen peroxide pretreatment mediated lignocellulose deconstruction and delignification

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Dong Tian ◽  
Yiyi Chen ◽  
Fei Shen ◽  
Maoyuan Luo ◽  
Mei Huang ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Acetic Acid ◽  
Synergistic Effect ◽  
Phosphoric Acid ◽  
Wheat Straw ◽  
Lignin Degradation ◽  
Acid Oxidation ◽  
Main Function ◽  
Corn Stalk ◽  
Peroxyacetic Acid

Abstract Background Peroxyacetic acid involved chemical pretreatment is effective in lignocellulose deconstruction and oxidation. However, these peroxyacetic acid are usually artificially added. Our previous work has shown that the newly developed PHP pretreatment (phosphoric acid plus hydrogen peroxide) is promising in lignocellulose biomass fractionation through an aggressive oxidation process, while the information about the synergistic effect between H3PO4 and H2O2 is quite lack, especially whether some strong oxidant intermediates is existed. In this work, we reported the PHP pretreatment system could self-generate peroxyacetic acid oxidant, which mediated the overall lignocellulose deconstruction, and hemicellulose/lignin degradation. Results The PHP pretreatment profile on wheat straw and corn stalk were investigated. The pathways/mechanisms of peroxyacetic acid mediated-PHP pretreatment were elucidated through tracing the structural changes of each component. Results showed that hemicellulose was almost completely solubilized and removed, corresponding to about 87.0% cellulose recovery with high digestibility. Rather high degrees of delignification of 83.5% and 90.0% were achieved for wheat straw and corn stalk, respectively, with the aid of peroxyacetic acid oxidation. A clearly positive correlation was found between the concentration of peroxyacetic acid and the extent of lignocellulose deconstruction. Peroxyacetic acid was mainly self-generated through H2O2 oxidation of acetic acid that was produced from hemicellulose deacetylation and lignin degradation. The self-generated peroxyacetic acid then further contributed to lignocellulose deconstruction and delignification. Conclusions The synergistic effect of H3PO4 and H2O2 in the PHP solvent system could efficiently deconstruct wheat straw and corn stalk lignocellulose through an oxidation-mediated process. The main function of H3PO4 was to deconstruct biomass recalcitrance and degrade hemicellulose through acid hydrolysis, while the function of H2O2 was to facilitate the formation of peroxyacetic acid. Peroxyacetic acid with stronger oxidation ability was generated through the reaction between H2O2 and acetic acid, which was released from xylan and lignin oxidation/degradation. This work elucidated the generation and function of peroxyacetic acid in the PHP pretreatment system, and also provide useful information to tailor peroxide-involved pretreatment routes, especially at acidic conditions. Graphical abstract

Zum stoffwechsel von aromaten, II. über die muconsäurespaltung von einfachen o-diphenolen / on the metabolism of aromatic compounds, ii * the muconic acid scission of simple o-diphenols

1973 ◽  
Vol 28 (11-12) ◽  
pp. 662-674 ◽  
Author(s):  
Günther Schulz ◽  
Erich Hecker
Keyword(s):  
Acetic Acid ◽  
Sulfuric Acid ◽  
Ethyl Acetate ◽  
Peracetic Acid ◽  
Aromatic Compounds ◽  
Time Course ◽  
Protocatechuic Acid ◽  
Uv Light ◽  
Steric Effects ◽  
Muconic Acid

Abstract The preparation of substituted cis,cis-muconic acids by oxidative ring scission of simple o-di-phenols with peracetic acid is investigated. Scission of pyrocatechol (1) to cis,cis-muconic acid (2) gives optimal yields, if acetic acid or ethyl acetate is used as solvent and if the solution is 15-20% with respect to sulfuric acid free peracetic acid comprising a one molar excess of oxidant. Under similar conditions, 3-tosylamino-pyrocatechol yields with peracetic acid the hitherto unknown α-tosylamino-cis,cis-muconic caid (18). 18 may be converted to α-tosylamino-traras,trans-muconic acid (19) by means of iodine, UV light or heating. From protocatechuic acid (4) under similar conditions not β-carboxy-cis,cis-muconic acid (5) is obtained, but rather β-carboxy-mucono-lactone (6 b, γ-carboxymethyl-β-carboxy-Δα-butenolide). As yet, this lactone has been accessible only from an isomer of β-carboxy-cis,cis-muconic acid, the latter being obtainable by enzymatic scission of protocatechuic acid (4). Steric effects are responsible for both, the formation of the free cis,cis-muconic acids 2 and 18 from pyrocatechol (1) and α-tosylamino-pyrocatechol, and the formation of the γ-lactone 6 b instead of β -carboxy-cis,cis-muconic acid by scission of protocatechuic acid (4). The time course of the reactions shows that - compared to pyrocatechol (1) - a 3-tosylamino-group enhances the peracetic acid scission, whereas a 4-carboxygroup as in 4 slows it down

ChemInform Abstract: ANODIC CHLORINATION OF AROMATIC COMPOUNDS IN ACETIC ACID

1974 ◽  
Vol 5 (51) ◽  
pp. no-no
Author(s):  
M. MASTRAGOSTINO ◽  
G. CASALBORE ◽  
S. VALCHER
Keyword(s):  
Acetic Acid ◽  
Aromatic Compounds

Pretreatment of wastewater containing a mixture of organic pollutants obtained from a CC2 plant by coagulation

2008 ◽  
Vol 58 (5) ◽  
pp. 1071-1077
Author(s):  
Bidhan C. Bag ◽  
Makireddi Sai ◽  
Mahavir P. Kaushik ◽  
Krishnamurthy Sekhar ◽  
Chiranjib Bahttacharya
Keyword(s):  
Acetic Acid ◽  
Organic Pollutants ◽  
Aromatic Compounds ◽  
Carboxymethyl Cellulose ◽  
Industrial Wastewater ◽  
Suspended Solids ◽  
Oxygen Demand ◽  
Total Suspended Solids ◽  
Manufacturing Plant ◽  
Colloidal Materials

Coagulation is one of the most important physicochemical treatment steps in industrial wastewater to reduce the suspended and colloidal materials responsible for colour and turbidity of the wastewater. The manufacturing plant of N,N′-Dichloro bis (2,4,6-trichlorophenyl) urea (CC2) produces wastewater containing pyridine, acetic acid and diphenyl urea (DPU). The wastewater also contains lot of suspended solids like CC2 and various poly-aromatic compounds. In our present investigation, our basic aim was to find an effective coagulation process for the pretreatment of wastewater discharged from the CC2 plant. Studies were conducted to find out a suitable and effective coagulant for pretreatment of this wastewater. Various coagulating agents such as alum, ferric chloride, sodium carboxymethyl cellulose (Na-CMC) were used. Alum was found to be the most effective coagulant. Coagulation of the wastewater resulted in the total suspended solids (TSS) removal in the range of 92–94% and chemical oxygen demand (COD) removal in the range of 59 to 65% at a dose of 500 mg L−1 of alum at a pH ≥ 7.0. After coagulation the concentration of pyridine in wastewater was found to be reduced by 10.0% and that of DPU 40–45% with a dosage of 500 mg L−1 alum.

scholarly journals Decontamination of cut carrot by Persteril® agent based on the action of peroxyacetic acid

2010 ◽  
Vol 28 (No. 6) ◽  
pp. 564-571 ◽  
Author(s):  
A. Landfeld ◽  
V. Erban ◽  
E. Kováříková ◽  
M. Houška ◽  
K. Kýhos ◽  
...  
Keyword(s):  
Drinking Water ◽  
Acetic Acid ◽  
Microbial Growth ◽  
Grocery Store ◽  
Brand Name ◽  
Peroxyacetic Acid ◽  
Agent Based ◽  
Fresh Vegetables ◽  
Yeasts And Molds ◽  
Initial Contamination

The use of cleaned and cut fresh vegetables for direct consumption without cooking is limited by the short shelf life caused by the fast growth of contaminating microflora. With the aim of reducing the contamination, we tested the possible use of peroxyacetic acid (brand name Persteril) as an additive. Peroxyacetic acid breaks down quickly into oxygen and acetic acid; with the latter quickly vaporising through the packaging. Tests were carried out on a model of pre-washed, cut, and re-washed carrots, which were left naturally contaminated to resemble real grocery store conditions. Four decontamination regimens were applied: (1) rinsing with ordinary tap (drinking) water, (2) rinsing with a 0.2% solution of Persteril, (3) rinsing with a 0.2% solution of Persteril + the addition of concentrated Persteril into the packaging before sealing, and (4) rinsing with a 0.2% solution of Persteril + the addition of concentrated Persteril into the packaging before sealing + another addition of concentrated Persteril after 24 hours. The total number of aerobe mesophilic microorganisms (TNM) and the numbers of yeasts and molds were monitored in the samples taken during 28-days of storage. The last decontamination regimen reduced the initial contamination by TNM by about 1× 104 CFU/g or 4 log units and no further microbial growth was observed during storage. Yeasts and molds were reduced by about 3.16 × 103 CFU/g or 3.5 log units. No statistically significant changes in colour, texture or taste were noted during storage. There was a slight change immediately after the application in the odour of samples treated with concentrated Persteril; however, the odour returned to original levels during storage.

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