scholarly journals Bleaching microcrystalline cellulose using hydrogen peroxide, peracetic acid, and ozone

BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 7991-8005
Author(s):  
Riku Kopra ◽  
Kari Vanhatalo ◽  
Sonja Päärnilä ◽  
Antti Pappinen ◽  
Olli Dahl
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Microcrystalline Cellulose ◽  
Peracetic Acid ◽  
Oxygen Demand ◽  
Raw Material ◽  
Paper Pulp ◽  
Traditional Use ◽  
Pharmaceutical Applications ◽  
Hydrolysis Process

AaltoCell™ based microcrystalline cellulose was bleached using hydrogen peroxide, peracetic acid, and ozone. The target brightness was set at 85% ISO brightness of the sheet (93% Y-brightness), which is white enough for the traditional use of microcrystalline cellulose. Both the paper pulp and dissolving pulp can be hydrolyzed using the AaltoCell™ process. Using paper pulp as a raw material, the brightness of the final microcrystalline cellulose decreased. The higher the temperature and retention time during the hydrolysis process, the greater the brightness loss. This effect can be explained by the so-called caramelization reaction. Due to this phenomenon, the microcrystalline cellulose should be bleached before using the product in food and pharmaceutical applications. The results showed that the target brightness was reached with ozone at doses of approximately 5 kg/ton with a reaction time of a few minutes; peroxide and peracetic acid required approximately twice the dose and a reaction time of at least 30 min. The concentrations of the chemical oxygen demand and total organic carbon in the pulp filtrate fraction varied with the bleaching chemicals used, with both values being low with ozone and the highest with peracetic acid.

Research on Synthesis Regularity of Epoxysuccinic Acid

2013 ◽  
Vol 316-317 ◽  
pp. 942-945
Author(s):  
Qing He Gao ◽  
Yi Can Wang ◽  
Zhi Feng Hou ◽  
Hui Juan Qian ◽  
Yuan Zhang ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Maleic Anhydride ◽  
Reaction Temperature ◽  
Raw Material ◽  
Molar Ratio ◽  
Mass Ratio ◽  
Synthesis System ◽  
Reaction Conditions ◽  
Sodium Hydrate

The yield of epoxysuccinic acid was obtained by determining the content of unreacted maleic anhydride and tartaric acid as a by-product in synthesis system. This method could calculate the yield of epoxysuccinic acid precisely and overcome the disadvantage of obtaining inpure product by recrystallization method. Epoxysuccinic Acid was synthesized using maleic anhydride as raw material, hydrogen peroxide as oxidizer and tungstate as catalyst. The effects of reaction temperature, reaction time, ratio of materials, dosage of oxidizer and catalyst on epoxidation and hydrolysis reaction was investigated. The results showed that the yield of epoxysuccinic acid was 88% when the reaction conditions were as follows: reaction temperature 65°C, reaction time 1.5h, catalyst dosage 3%(based on mass of maleic anhydride), molar ratio of sodium hydrate to maleic anhydride 2:1, mass ratio of hydrogen peroxide to maleic anhydride 1:1.

scholarly journals COD removal from petrochemical wastewater by UV/hydrogen peroxide, UV/persulfate and UV/percarbonate: biodegradability improvement and cost evaluation

2016 ◽  
Vol 6 (4) ◽  
pp. 484-494 ◽  
Author(s):  
Ali Akbar Babaei ◽  
Farshid Ghanbari
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Oxygen Demand ◽  
Ultra Violet ◽  
High Strength ◽  
Cod Removal ◽  
Cost Evaluation ◽  
Petrochemical Wastewater ◽  
Ferrous Ions ◽  
Initial Ph

The petrochemical industry has been highly considered by environmentalists since it can affect the environment through the production of high strength wastewater. This study investigates chemical oxygen demand (COD) removal from petrochemical wastewater by ultra violet (UV)/oxidant systems with varying dosages of oxidants, initial pH values and reaction time. Hydrogen peroxide (H2O2), persulfate (PS) and percarbonate (PC) were used as oxidants. The results showed that pH = 3.0 was suitable for H2O2 and PC, while PS had the best performance at pH = 7.0. The presence of ferrous ions improved the removal efficiency, especially in the case of UV/PC. However, COD removal efficiencies of UV/PS and UV/H2O2 were more effective than that of the UV/PC system. The biochemical oxygen demand (BOD)/COD ratio achieved >0.4 by UV/PS/Fe2+, UV/H2O2 and UV/H2O2/Fe2+ systems. Complete decolorization occurred for all the UV/oxidant systems after only 30 min reaction time. Besides the effective performances of PS and H2O2 in COD removal, PC was considered as an inexpensive oxidant. The order of total costs based on kg COD removed was: UV/PS/Fe2+ > UV/PS > UV/H2O2/Fe2+ > UV/H2O2 > UV/PC/Fe2+ > UV/PC. In conclusion, UV/H2O2 displayed an effective, applicable and clean process for petrochemical wastewater treatment.

Environmental benefits of magnesium hydroxide-based peroxide bleaching of mechanical pulp – mill results

TAPPI Journal ◽  
2013 ◽  
Vol 12 (6) ◽  
pp. 9-15 ◽  
Author(s):  
TOMI HIETANEN ◽  
JUHA TAMPER ◽  
KAJ BACKFOLK
Keyword(s):  
Sodium Hydroxide ◽  
Magnesium Hydroxide ◽  
Oxygen Demand ◽  
Pulp Mill ◽  
Transition Metal Ions ◽  
Environmental Benefits ◽  
Raw Material ◽  
Paper Machine ◽  
High Brightness ◽  
Peroxide Bleaching

The use of a new, technical, high-purity magnesium hydroxide-based peroxide bleaching additive was evaluated in full mill-scale trial runs on two target brightness levels. Trial runs were conducted at a Finnish paper mill using Norwegian spruce (Picea abies) as the raw material in a conventional pressurized groundwood process, which includes a high-consistency peroxide bleaching stage. On high brightness grades, the use of sodium-based additives cause high environmental load from the peroxide bleaching stage. One proposed solution to this is to replace all or part of the sodium hydroxide with a weaker alkali, such as magnesium hydroxide. The replacement of traditional bleaching additives was carried out stepwise, ranging from 0% to 100%. Sodium silicate was dosed in proportion to sodium hydroxide, but with a minimum dose of 0.5% by weight on dry pulp. The environmental effluent load from bleaching of both low and high brightness pulps was significantly reduced. We observed a 35% to 48% reduction in total organic carbon (TOC), 37% to 40% reduction in chemical oxygen demand (COD), and 34% to 60% reduction in biological oxygen demand (BOD7) in the bleaching effluent. At the same time, the target brightness was attained with all replacement ratios. No interference from transition metal ions in the process was observed. The paper quality and paper machine runnability remained good during the trial. These benefits, in addition to the possibility of increasing production capacity, encourage the implementation of the magnesium hydroxide-based bleaching concept.

Advanced Treatment of Coking Wastewater by Oxidation Process Using Pyrite and Hydrogen Peroxide

2013 ◽  
Vol 726-731 ◽  
pp. 2521-2525
Author(s):  
Zhi Yong Zhang ◽  
De Li Wu
Keyword(s):  
Hydrogen Peroxide ◽  
Oxidation Process ◽  
Low Cost ◽  
Oxygen Demand ◽  
Utilization Efficiency ◽  
Advanced Treatment ◽  
Coking Wastewater ◽  
Second Stage ◽  
Potential Alternative ◽  
High Utilization

Coking wastewater is a kind of recalcitrant wastewater including complicate compositions. Advanced treatment of coking wastewater by Fenton-Like reaction using pyrite as catalyst was investigated in this paper. The results show that the chemical oxygen demand (COD) of coking wastewater decreased significantly by method of coagulation combined with two-stage oxidation reaction. COD of wastewater can decrease from 250mg/l to 45mg/l after treatment, when 2g/L pyrite was used in each stage oxidation and the dosage of hydrogen peroxide (H2O2) is 0.2ml/l for first stage treatment, 0.1ml/l for second stage treatment respectively. The pyrite is effective to promote Fenton-Like reaction with low cost due to high utilization efficiency of H2O2, moreover, catalyst could be easily recovered and reused. The Fenton-Like reaction might be used as a potential alternative to advanced treatment of recalcitrant wastewater.

scholarly journals Inhibition Properties of Arylsulfatase and β-Glucuronidase by Hydrogen Peroxide, Hypochlorite, and Peracetic Acid

ACS Omega ◽  
2021 ◽  
Author(s):  
Shu-shu Zhong ◽  
Jun Zhang ◽  
Ze-hua Liu ◽  
Zhi Dang ◽  
Yu Liu
Keyword(s):  
Hydrogen Peroxide ◽  
Peracetic Acid

scholarly journals Clinoptilolite as a natural, active zeolite catalyst for the chemical transformations of geraniol

2021 ◽  
Author(s):  
Anna Fajdek-Bieda ◽  
Agnieszka Wróblewska ◽  
Piotr Miądlicki ◽  
Jadwiga Tołpa ◽  
Beata Michalkiewicz
Keyword(s):  
Reaction Time ◽  
Nitrogen Adsorption ◽  
Carbon Chain ◽  
Raw Material ◽  
Chemical Transformations ◽  
Renewable Biomass ◽  
Ft Ir ◽  
Catalyst Content ◽  
Favorable Conditions ◽  
Instrumental Methods

AbstractThis work presented the studies with the natural zeolite—clinoptilolite as the catalyst for the isomerization of geraniol. During the research, it turned out that the studied process is much more complicated, and not only isomerization takes place in it, but also dehydration, oxidation, dimerization, cyclization and fragmentation of the carbon chain. Geraniol is an organic raw material which can be obtained not only by a chemical synthesis but also from plants (renewable biomass) by distillation or extraction method, for example a source of geraniol can be a plant—geranium. Before catalytic tests clinoptilolite was characterized by the instrumental methods, such as: XRD, porosity studies—nitrogen adsorption at 77 K, SEM, EDXRF, and FT-IR. Gas chromatography analyses showed that the main products of geraniol isomerization process were 6,11-dimethyl-2,6,10-dodecatrien-1-ol and thumbergol. The selectivity of 6,11-dimethyl-2,6,10-dodecatrien-1-ol and thumbergol depended on the temperature, catalyst content and reaction time. These parameters were changed in the following ranges: 80–150 °C (temperature), 5–15 wt% (catalyst content) and 15–1440 min. (reaction time). The most favorable conditions for 6,11-dimethyl-2,6,10-dodecatrien-1-ol and thumbergol obtaining were: temperature 140 ºC, catalyst content 12.5 wt% and reaction time 180 min. At these conditions, the conversion of geraniol amounted to 98 mol%, and the selectivities of 6,11-dimethyl-2,6,10-dodecatrien-1-ol and thumbergol amounted to 14 and 47 mol%, respectively.

scholarly journals Study on Chromaticity Removal from Mineral Processing Wastewater with Salicylic Hydroxamic Acid by Granular Activated Carbon Catalyzed Ozonation

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 359
Author(s):  
Liping Zhang ◽  
Shengnian Wu ◽  
Nan Zhang ◽  
Ruihan Yao ◽  
Eryong Wu
Keyword(s):  
Activated Carbon ◽  
Reaction Time ◽  
Hydroxamic Acid ◽  
Ph Value ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Mineral Processing ◽  
Ultraviolet Absorption Spectrum ◽  
Experimental Conditions ◽  
Removal Ratio

Salicylic hydroxamic acid is a novel flotation reagent used in mineral processing. However, it impacts the flotation wastewater leaving behind high chromaticity which limits its reuse and affects discharge for mining enterprises. This study researched ozonation catalyzed by the granular activated carbon (GAC) method to treat the chromaticity of the simulated mineral processing wastewater with salicylic hydroxamic acid. The effects of pH value, ozone (O3) concentration, GAC dosage, and reaction time on chromaticity and chemical oxygen demand (CODCr) removal were discussed. The results of individual ozonation experiments showed that the chromaticity removal ratio reached 79% and the effluent chromaticity exceeded the requirement of reuse and discharge when the optimal experimental conditions were pH value 3, ozone concentration 6 mg/L, and reaction time 40 min. The orthogonal experimental results of catalytic ozonation with GAC on chromaticity removal explained that the chromaticity removal ratio could reach 96.36% and the chromaticity of effluent was only 20 when the optimal level of experimental parameters was pH value 2.87, O3 concentration 6 mg/L, GAC dosage 0.06 g/L, reaction time 60 min respectively. The degradation pathway of salicylic hydroxamic acid by ozonation was also considered based on an analysis with ultraviolet absorption spectrum and high-performance liquid chromatography (HPLC).

scholarly journals The Use of Sodium Carbonate—Hydrogen Peroxide (2/3) in the Modified Fenton Reaction to Degradation PAHs in Coke Wastewater

Proceedings ◽  
2019 ◽  
Vol 16 (1) ◽  
pp. 44
Author(s):  
Kozak ◽  
Włodarczyk-Makuła
Keyword(s):  
Hydrogen Peroxide ◽  
Organic Pollutants ◽  
Sodium Carbonate ◽  
Uv Light ◽  
Oxygen Demand ◽  
Organic Matrix ◽  
Coke Wastewater ◽  
Polycyclic Aromatic ◽  
Pahs Concentration ◽  
Modified Fenton

The aim of the research was to determine the effectiveness of removing micro-organic pollutants, including PAHs, using the modified Fenton method. The tested material was pretreated coke wastewater, in which the initial chemical oxygen demand (COD) value and initial polycyclic aromatic hydrocarbons (PAHs) concentration were determined. The samples were then subjected to an oxidation procedure. Before the process, the pH was adjusted to 3.5–3.8. Next, the following doses of sodium carbonate—hydrogen peroxide (2/3): 1.2 g/L, 1.5 g/L and 2 g/L, and a constant dose of iron sulphate were added. The next step was exposing the samples to UV light for 6 min and separating the organic matrix from the samples of wastewater. After the tests, the final value of the COD and the final PAHs concentration were determined. The average content of organic pollutants in pretreated coke wastewater determined by the COD index was 538 mg/L, and after the oxidation process, the COD index decreased in the range from 9 to 29%. The efficiency of the degradation of the sum of 16 PAHs was varied and was in the range of 94–97.6%. The research results show that sodium carbonate—hydrogen peroxide (2/3) can be used for the degradation of organic pollutants, such as PAHs, in the modified Fenton process.

scholarly journals Investigating microcrystalline cellulose crystallinity using Raman spectroscopy

Cellulose ◽  
2021 ◽  
Author(s):  
Ana Luiza P. Queiroz ◽  
Brian M. Kerins ◽  
Jayprakash Yadav ◽  
Fatma Farag ◽  
Waleed Faisal ◽  
...  
Keyword(s):  
Raman Spectra ◽  
Microcrystalline Cellulose ◽  
Web Application ◽  
Principal Component ◽  
Raw Material ◽  
Least Squares Regression ◽  
Analysis Model ◽  
General Reference ◽  
Material Source ◽  
Univariate Model

AbstractMicrocrystalline cellulose (MCC) is a semi-crystalline material with inherent variable crystallinity due to raw material source and variable manufacturing conditions. MCC crystallinity variability can result in downstream process variability. The aim of this study was to develop models to determine MCC crystallinity index (%CI) from Raman spectra of 30 commercial batches using Raman probes with spot sizes of 100 µm (MR probe) and 6 mm (PhAT probe). A principal component analysis model separated Raman spectra of the same samples captured using the different probes. The %CI was determined using a previously reported univariate model based on the ratio of the peaks at 380 and 1096 cm−1. The univariate model was adjusted for each probe. The %CI was also predicted from spectral data from each probe using partial least squares regression models (where Raman spectra and univariate %CI were the dependent and independent variables, respectively). Both models showed adequate predictive power. For these models a general reference amorphous spectrum was proposed for each instrument. The development of the PLS model substantially reduced the analysis time as it eliminates the need for spectral deconvolution. A web application containing all the models was developed. Graphic abstract

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