Enhanced coagulation with in situ manganese dioxide on removal of humic acid in micro-polluted water

2015 ◽  
Vol 72 (3) ◽  
pp. 406-414
Author(s):  
Yubin Zeng ◽  
Ziyang Zeng ◽  
Junlin Wang
Keyword(s):  
Humic Acid ◽  
Manganese Dioxide ◽  
Ph Value ◽  
Orthogonal Experiment ◽  
Surface Characteristics ◽  
Polluted Water ◽  
Enhanced Coagulation ◽  
Total Solids ◽  
Solids Content

The morphology and surface characteristics of manganese dioxide (MnO2) formed in situ, which was prepared through the oxidation of MnSO4 using KMnO4, were studied. The effects of factors including the form of MnO2, dosage, pH, dosing sequence of in situ MnO2 on the enhanced coagulation were systematically evaluated. The results of analysis by the UV254 and permanganate index CODMn methods indicated that humic acid removal increased from 9.2 and 2.5% to 55.0 and 38.9%, when 10 mg/L of the in situ MnO2 was added in the presence of 2 mg/L of polyaluminum sulfate. The studies of orthogonal experiment revealed that coagulation was most affected by the pH, whereas the dosage of in situ MnO2 and slow stirring duration exhibited a weaker effect. At a pH value of 4.0, in situ MnO2 dosage of 10 mg/L, slow stir over 40 min, and the total solids content was 20 mg/L, the humic acid removal by UV254 and CODMn methods reached 71.2 and 61.2%. These results indicated that the presence of in situ MnO2 enhanced the coagulation and removal of humic acid from water.

scholarly journals In Situ Preparation of Novel Porous Nanocomposite Hydrogel as Effective Adsorbent for the Removal of Cationic Dyes from Polluted Water

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3002 ◽  
Author(s):  
Badr M. Thamer ◽  
Ali Aldalbahi ◽  
Meera Moydeen A. ◽  
Mohamed H. El-Newehy
Keyword(s):  
Linear Models ◽  
Adsorption Process ◽  
Ph Value ◽  
Low Cost ◽  
Freundlich Isotherm ◽  
Polymerization Process ◽  
Polluted Water ◽  
Swelling Properties ◽  
Hydrogel Nanocomposite

The use of some hydrogels as adsorbents for pollutants removal from wastewater is limited due to their high swelling properties and the difficulty in recovering them after the adsorption process. To overcome these problems, a new hydrogel nanocomposite based on chitosan-grafted-polyacrylic acid/oxidized electrospun carbon nanofibers (CT-g-PAA/O-ECNFs) was prepared by an in situ grafting polymerization process. The prepared hydrogel nanocomposite was used as a novel effective and highly reusable adsorbent for the removal of methylene blue (MB) from polluted water with low cost. The morphology and the structure of CT-g-PAA/O-ECNFs were investigated by numerous techniques. The effect of incorporating O-ECNFs on the swelling capability of the prepared hydrogel was explored in distillated water and MB solution at normal pH. The effect of parameters including ratio of O-ECNFs, contact time, pH, initial concentration, and temperature on adsorption process were explored. The adsorption isotherm and kinetic were studied by numerous non-linear models. The obtained results confirmed that the incorporation of O-ECNFs into the hydrogel network decreased the swelling capacity and improved its ability towards MB dye removal. The adsorption process depended on the pH value of the dye solution. Additionally, the adsorption and kinetic results were fitted using the Freundlich isotherm model and pseudo second order model (PSO), respectively. Moreover, the new adsorbents can be recycled for at least five cycles keeping its adsorption capacity and can be easily recovered without loss in its initial weight.

A pilot web former designed to study retention-formation relationships

2010 ◽  
Vol 25 (2) ◽  
pp. 185-194
Author(s):  
Anna Svedberg ◽  
Tom Lindström
Keyword(s):  
Pilot Scale ◽  
Operating Conditions ◽  
Montmorillonite Clay ◽  
Speed Ratio ◽  
Good Reproducibility ◽  
Total Solids ◽  
Retention Aids ◽  
Solids Content ◽  
Relationship Of ◽  
The Relationship

Abstract A pilot-scale fourdrinier former has been developed for the purpose of investigating the relationship between retention and paper formation (features, retention aids, dosage points, etc.). The main objective of this publication was to present the R-F (Retention and formation)-machine and demonstrate some of its fields of applications. For a fine paper stock (90% hardwood and 10% softwood) with addition of 25% filler (based on total solids content), the relationship between retention and formation was investigated for a microparticulate retention aid (cationic polyacrylamide together with anionic montmorillonite clay). The retention-formation relationship of the retention aid system was investigated after choosing standardized machine operating conditions (e.g. the jet-to-wire speed ratio). As expected, the formation was impaired when the retention was increased. Since good reproducibility was attained, the R-F (Retention and formation)-machine was found to be a useful tool for studying the relationship between retention and paper formation.

scholarly journals Effects of particle formation behavior on the properties of fish oil microcapsules fabricated using a micro-fluidic jet spray dryer

2020 ◽  
Vol 17 (1) ◽  
pp. 27-36
Author(s):  
Xingxing Xiong ◽  
Shengyu Zhang ◽  
Nan Fu ◽  
Hong Lei ◽  
Winston Duo Wu ◽  
...  
Keyword(s):  
Fish Oil ◽  
Oxidative Stability ◽  
Particle Formation ◽  
Core Material ◽  
Wall Material ◽  
Spray Dryer ◽  
Drying Temperature ◽  
Total Solids ◽  
Formation Behavior ◽  
Solids Content

Abstract Fish oil was encapsulated with whey protein isolate (WPI) as wall material using a Micro-Fluidic Jet Spray Dryer. The effects of core/wall material ratio, drying temperature and total solids content on the properties of microcapsules were studied. Low core/wall material ratios at 1:5 and 1:3 resulted in high encapsulation efficiency (EE) and excellent oxidative stability of microparticles during storage. Reducing the inlet temperature from 160 to 110 °C remarkably decreased EE from around 99 to 64.8%, associated with substantial increases in peroxide value during storage. The total solids content mainly altered the morphology of microcapsules, showing little influence on EE and oxidative stability. We proposed that the different drying conditions impacted on particle formation behavior during spray drying, which could be a crucial factor responsible for the differences in the quality attributes of microparticles. A low core/wall material ratio and high drying temperature facilitated the formation of a rigid protein skin at droplet surface during drying, whereas a high solids fraction in the droplets could limit possible droplet shrinkage. These factors contributed positively to the encapsulation of the lipophilic core material.

scholarly journals Regression Analysis of Orthogonal, Cylindrical and Multivariable Color Parameters for Colorimetric Surface pH Measurement of Materials

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3682
Author(s):  
Katarína Vizárová ◽  
Izabela Vajová ◽  
Naďa Krivoňáková ◽  
Radko Tiňo ◽  
Zdenko Takáč ◽  
...  
Keyword(s):  
Ph Value ◽  
Critical Factor ◽  
Ph Measurement ◽  
Ph Indicator ◽  
Water Quality Control ◽  
Quality Management Systems ◽  
Surface Ph ◽  
Regression Parameters ◽  
Ph Detection

The surface pH is a critical factor in the quality and longevity of materials and products. Traditional fast colorimetric pH detection-based tests such as water quality control or pregnancy tests, when results are determined by the naked eye, cannot provide quantitative values. Using standard pH papers, paper-printed comparison charts, or colorimetric microfluidic paper-based analytical devices is not suitable for such technological applications and quality management systems (QMSs) where the particular tested material should contain a suitable indicator in situ, in its structure, either before or after the process, the technology or the apparatus that are being tested. This paper describes a method based on the combination of impregnation of a tested material with a pH indicator in situ, its exposure to a process of technology whose impact on pH value is to be tested, colorimetric pH measurement, and approximation of pH value using derived pH characteristic parameters (pH-CPs) based on CIE orthogonal and cylindrical color variables. The hypotheses were experimentally verified using the methyl red pH indicator, impregnating the acid lignin-containing paper, and preparing a calibration sample set with pH in the range 4 to 12 using controlled alkalization. Based on the performed measurements and statistical evaluation, it can be concluded that the best pH-CPs with the highest regression parameters for pH are √∆E, ln (a),√∆H (ab), a/L, h/b and ln (b/a). The experimental results show that the presented method allows a good estimation of pH detection of the material surfaces.

scholarly journals Green Electrospinning of Polymer Latexes: A Systematic Study of the Effect of Latex Properties on Fiber Morphology

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 706
Author(s):  
Edurne Gonzalez ◽  
Aitor Barquero ◽  
Belén Muñoz-Sanchez ◽  
María Paulis ◽  
Jose Ramon Leiza
Keyword(s):  
Systematic Study ◽  
Molar Mass ◽  
Aqueous Dispersion ◽  
Particle Packing ◽  
Fiber Morphology ◽  
Polymer Particles ◽  
Total Solids ◽  
Hydrophobic Polymers ◽  
Safe Technology ◽  
Solids Content

Green electrospinning is a relatively new promising technology in which a polymer (latex) can be spun from an aqueous dispersion with the help of a template polymer. This method is a green, clean and safe technology that is able to spin hydrophobic polymers using water as an electrospinning medium. In this article, a systematic study that investigates the influence of the template polymer molar mass, the total solids content of the initial dispersion and the particle/template ratio is presented. Furthermore, the influence of the surfactant used to stabilize the polymer particles, the surface functionality of the polymer particles and the use of a bimodal particle size distribution on the final fiber morphology is studied for the first time. In green electrospinning, the viscosity of the initial complex blend depends on the amount and molar mass of the template polymer but also on the total solids content of the dispersion to be spun. Thus, both parameters must be carefully taken into account in order to fine-tune the final fiber morphology. Additionally, the particle packing and the surface chemistry of the polymer particles also play an important role in the obtained nanofibers quality.

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