scholarly journals Oxidative Degradation of Chlorinated Ethylenes by Hydrogen Peroxide, Tungstate, and Ammonium Salt at Room Temperature

2004 ◽  
Vol 27 (9) ◽  
pp. 611-614
Author(s):  
Tetsuji OKAMOTO ◽  
Morimasa SUZUKI
Keyword(s):  
Hydrogen Peroxide ◽  
Ammonium Salt ◽  
Room Temperature ◽  
Oxidative Degradation ◽  
Chlorinated Ethylenes

Studies on an Ecofriendly Oxidative Degradation System for Phenol

2013 ◽  
Vol 798-799 ◽  
pp. 116-119
Author(s):  
Ying Zhu ◽  
Qing Pan ◽  
Ran Li ◽  
Xiao Bin Chen ◽  
Xing Yue Ji ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Room Temperature ◽  
Phenol Degradation ◽  
Oxidative Degradation ◽  
Factors Influencing ◽  
Degradation Ratio ◽  
Fe Complex ◽  
Oxidative System

An ecofriendly advanced oxidative system was studied for the degradation of phenol. This system was composed of a self-made coordinated Fe complex and hydrogen peroxide. Factors influencing the degradation were explored. Suitable technology conditions were given as: hydrogen peroxide 2.2*10-4mol/L, catalyst 2.5*10-7mol/L, pH 11.5, room temperature and time 60 minute. Under this condition, phenol degradation ratio can be achieved to 99.93%.

A review of lignin hydrogen peroxide oxidation chemistry with emphasis on aromatic aldehydes and acids

Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ajinkya More ◽  
Thomas Elder ◽  
Zhihua Jiang
Keyword(s):  
Hydrogen Peroxide ◽  
Oxidative Degradation ◽  
Reaction Medium ◽  
Dicarboxylic Acids ◽  
Aromatic Aldehydes ◽  
Product Distribution ◽  
Reaction Conditions ◽  
Alkaline Conditions ◽  
The Stability ◽  
Oxidation Chemistry

Abstract This review discusses the main factors that govern the oxidation processes of lignins into aromatic aldehydes and acids using hydrogen peroxide. Aromatic aldehydes and acids are produced in the oxidative degradation of lignin whereas mono and dicarboxylic acids are the main products. The stability of hydrogen peroxide under the reaction conditions is an important factor that needs to be addressed for selectively improving the yield of aromatic aldehydes. Hydrogen peroxide in the presence of heavy metal ions readily decomposes, leading to minor degradation of lignin. This degradation results in quinones which are highly reactive towards peroxide. Under these reaction conditions, the pH of the reaction medium defines the reaction mechanism and the product distribution. Under acidic conditions, hydrogen peroxide reacts electrophilically with electron rich aromatic and olefinic structures at comparatively higher temperatures. In contrast, under alkaline conditions it reacts nucleophilically with electron deficient carbonyl and conjugated carbonyl structures in lignin. The reaction pattern in the oxidation of lignin usually involves cleavage of the aromatic ring, the aliphatic side chain or other linkages which will be discussed in this review.

Stability of dronabinol capsules when stored frozen, refrigerated, or at room temperature

2016 ◽  
Vol 73 (14) ◽  
pp. 1088-1092 ◽  
Author(s):  
Michael F. Wempe ◽  
Alan Oldland ◽  
Nancy Stolpman ◽  
Tyree H. Kiser
Keyword(s):  
High Performance ◽  
Room Temperature ◽  
Oxidative Degradation ◽  
Storage Condition ◽  
Sesame Oil ◽  
Forced Degradation ◽  
Product Packaging ◽  
Time Points ◽  
The Stability ◽  
Minimal Reduction

Abstract Purpose Results of a study to determine the 90-day stability of dronabinol capsules stored under various temperature conditions are reported. Methods High-performance liquid chromatography (HPLC) with ultraviolet (UV) detection was used to assess the stability of dronabinol capsules (synthetic delta-9-tetrahydrocannabinol [Δ9-THC] mixed with high-grade sesame oil and other inactive ingredients and encapsulated as soft gelatin capsules) that were frozen, refrigerated, or kept at room temperature for three months. The dronabinol capsules remained in the original foil-sealed blister packs until preparation for HPLC–UV assessment. The primary endpoint was the percentage of the initial Δ9-THC concentration remaining at multiple designated time points. The secondary aim was to perform forced-degradation studies under acidic conditions to demonstrate that the HPLC–UV method used was stability indicating. Results The appearance of the dronabinol capsules remained unaltered during frozen, cold, or room-temperature storage. Regardless of storage condition, the percentage of the initial Δ9-THC content remaining was greater than 97% for all evaluated samples at all time points over the three-month study. These experimental data indicate that the product packaging and the sesame oil used to formulate dronabinol capsules efficiently protect Δ9-THC from oxidative degradation to cannabinol; this suggests that pharmacies can store dronabinol capsules in nonrefrigerated automated dispensing systems, with a capsule expiration date of 90 days after removal from the refrigerator. Conclusion Dronabinol capsules may be stored at room temperature in their original packaging for up to three months without compromising capsule appearance and with minimal reduction in Δ9-THC concentration.

scholarly journals A Mn(iii) polyoxotungstate in the oxidation of organosulfur compounds by H2O2 at room temperature: an environmentally safe catalytic approach

2016 ◽  
Vol 6 (9) ◽  
pp. 3271-3278 ◽  
Author(s):  
Tiago A. G. Duarte ◽  
Sónia M. G. Pires ◽  
Isabel C. M. S. Santos ◽  
Mário M. Q. Simões ◽  
M. Graça P. M. S. Neves ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Room Temperature ◽  
Organosulfur Compounds ◽  
Keggin Type ◽  
Environmentally Safe

A manganese monosubstituted Keggin-type polyoxometalate was used as a catalyst in the oxidation of recalcitrant organosulfur compounds by hydrogen peroxide at room temperature.

scholarly journals Studies on the Preservation of Raw Cow’s Milk by Chemical Method

1970 ◽  
Vol 42 (3) ◽  
pp. 317-326 ◽  
Author(s):  
F Rokhsana ◽  
UK Das ◽  
R Yeasmin ◽  
A Nahar ◽  
S Parveen
Keyword(s):  
Hydrogen Peroxide ◽  
Chemical Method ◽  
Room Temperature ◽  
Storage Period ◽  
Total Coliform ◽  
Human Consumption ◽  
Milk Products ◽  
E Coli ◽  
Keeping Quality ◽  
Control Milk

Studies carried out to develop a technique for the preservation of cow's milk in raw condition using hydrogen peroxide (H2O2) as a preservative. Fresh cow’s milk was collected and experiments were conducted by four treatments in order to achieve the optimum condition of storage. The treatments were with various concentration of H2O2 starting from 0.05 %, 0.1 %, 0.2 %, 0.3 %, 0.4 %, & 0.5 %. Treated milk with 0.05 % concentration of H2O2 had storage period of 20 days compared to that of the control one (5 days only) in refrigerated temperature (±8°C). On the other hand hydrogen peroxide treated milk (0.05 %) had a storage period of 8 hours at room temperature (±28°C). Results also showed that the higher concentration of H2O2 had no effect on storage period than that of control. Milk products like kheer and halawa prepared by treated milk and stored for 20 days showed almost nil growth of total coliform and E. coli which means that food products prepared from hydrogen peroxide treated milk is safe for human consumption. Key words: Raw, Storage, Hydrogen peroxide, Preservative, keeping quality, Pasteurization, deteriorated, MPN. Bangladesh J. Sci. Ind. Res. 42(3), 317-326, 2007

scholarly journals Linseed oil: Characterization and study of its oxidative degradation

2020 ◽  
Vol 71 (1) ◽  
pp. 337 ◽  
Author(s):  
B. M. Berto ◽  
R. K.A. Garcia ◽  
G. D. Fernandes ◽  
D. Barrera-Arellano ◽  
G. G. Pereira
Keyword(s):  
Fatty Acid ◽  
Oxidative Stability ◽  
Induction Period ◽  
Room Temperature ◽  
Linseed Oil ◽  
Oxidative Degradation ◽  
Acid Value ◽  
Quality Parameters ◽  
Time Intervals ◽  
Accelerated Oxidation

This paper proposes to characterize and monitor the degradation of linseed oil under two oxidation conditions using some traditional oxidative and quality parameters. The experimental section of this study was divided into 2 stages. In the first one, three commercial linseed oil samples (OL1, OL2, and OL3) were characterized according to oxidative stability (90 °C) and fatty acid composition. In the second stage, the OL1 sample, selected due to its availability, was subjected to the following oxidation procedures: storage at room temperature conditions with exposure to light and air (temperature ranging from 7 to 35 °C) for 140 days and accelerated oxidation at 100 °C for 7h. Samples were collected at different time intervals and analyzed for oxidative stability (90 °C), peroxide value, and acid value. The results showed that all the samples presented a similar fatty acid profile and that the OL3 sample showed a higher induction period (p < 0.05). Regarding the oxidative degradation, the induction period of the OL1 sample reduced from 9.7 to 5.7 and 9.7 to 6.3 during 140 days of storage under room temperature and 7 h of accelerated oxidation, respectively. The end of induction period of the OL1 sample is expected to occur within 229 days according to an exponential mathematical model fitted to the induction period values at different temperatures. In addition, the OL1 sample met the limits proposed by Codex and Brazilian regulations for peroxide and acid values during the oxidation time intervals.

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