Impact Of Surfactant Addition Research Articles

Bioaugmentation of Pentachlorophenol by Pseudomonas mosseli HM627603 and P. putida HM627611 in secondary treated wastewater UVC254 inactivation

The accumulation of organic pollutants, pesticides, fertilizers, etc. causing critical health trouble to humans, animals, many aquatic ecosystems, and plants. This study evaluated the elimination of the pesticides as pentachlorophenol (PCP: 800 mg L−1) by bioaugmentation process in sterile secondary treated wastewater (STWW) and mineral salt medium (MSM). Also, the impact of surfactant addition (sodium dodecyl sulfate ‘SDS’ and Cetyltrimethylammonium bromide ‘CTAB’) in PCP elimination phenomena. The PCP rate in different treatments was analyzed by high-performance liquid chromatography (HPLC). The bacteria biomass was measured through a spectroscopy approach at 600 nm optical density (OD600). The chloride rates were determinate through the calorimetric approach. In addition, the STWW disinfection was released through the UV radiation technique. The HPLC analysis confirmed that the strain P. mosseli HM627603 and P. putida HM627611 were able to tolerate and remove respectively 99.6 and 76.12% of PCP (800 mg. L-1). The chloride rates increased after 7 days in all treatments with a value of 0.64 to 3.12 g L-1 for P. mosseli HM627603 in MSM. The SDS surfactant induces an increase in the PCP elimination from STWW through P. putida HM627611. The bacterial inactivation became quicker within 80 seconds in sterile STWW supplemented with PCP at 800 mg L-1 for P. putida HM627611 tested in agar medium.

Surfactant changes lead adsorption behaviors and mechanisms on microplastics

The impact of surfactant addition on the adsorption performance of lead ion (Pb2+) as a typical heavy metal ion on three microplastics was investigated. The types of microplastics (polyethylene (PE), polypropylene (PP) and polymethylmethacrylate (PMMA)) and surfactants (triton X-100 (TX-100), 1-hexadecylpyridinium bromide (HDPB), and sodium dodecyl benzenesulfonate (SDBS)), adsorption time, concentration of Pb2+, and coexisting ions was systematically investigated, and the characteristics of adsorption of Pb2+ by microplastics were analyzed. The experimental results showed that the adsorption capacity of Pb2+ on three micropalstics was different. The adsorption capacity of Pb2+ on the three microplastics without surfactants was: 4.21 (PMMA) > 2.01 (PE) > 1.57 mg g−1 (PP). The addition of surfactants resulted in a higher hydrophilicity of microplastics, and obviously improved the adsorption ability of microplastics for lead ions. SDBS can significantly enhance the adsorption of Pb2+ on three microplastics compared with other two surfactants (TX100 and HDPB). The highest adsorption capacity of Pb2+ on the three microplastics with addition of SDBS solution was: 7.87 (PMMA) > 7.20 (PE) > 7.02 mg g−1 (PP). With the increase of adsorption time and Pb2+ concentration, the adsorption efficiency of microplastics for Pb2+ first increased and then decreased. The pH of solution had a great influence on the adsorption of Pb2+ by microplastics. The results of coexisting ion experiments demonstrated that when lead ion and copper ion coexist, the two ions have competitive adsorption phenomenon on PP. This research explored the adsorption characteristics of lead ions by microplastics with addition of surfactants, which can provide theoretical basis for further study of heavy metal enrichment and environmental behavior of microplastics in the environment.

Impact of surfactant addition on non-Newtonian fluid behavior during viscous fingering in Hele-Shaw cell

We present an experimental study of viscous fingering caused by the displacement of an oil phase by non-Newtonian fluids such as Carbopol® 940 with and without surfactant (SDS) addition in a radial Hele-Shaw cell. When polymer solutions are injected, a variety of fingering patterns as a function of flow rate are observed, which differ from the classical Saffman-Taylor instability. We have shown that if the surfactant concentration locally decreases the interfacial tension, it also leads to a reduction of viscosity and hence results in an increasing impact on the capillary number. We found that surfactant-polymer solutions have wider fingers with increasing flow rates in contrast with Newtonian solutions. Our study also revealed that the relative finger width of both non-Newtonian experiments with and without the surfactant converge asymptotically to the same value. We think that this phenomenon is caused by the decrease in surfactant concentration in the vicinity of the tip as the finger is growing so that the shear-thinning features of polymer prevail at long time.

Hydrogels of sodium alginate in cationic surfactants: Surfactant dependent modulation of encapsulation/release toward Ibuprofen

The interaction of cetyltrimethylammoium bromide (CTAB) and its gemini homologue (butanediyl-1,4-bis (dimethylcetylammonium bromide), 16-4-16 with biocompatible polymer sodium alginate (SA) has been investigated in aqueous medium. Addition of K2CO3 influences viscoelastic properties of surfactant impregnated SA via competition between electrostatic and hydrophobic interactions. Viscosity of these polymer-surfactant systems increases with increase in concentration of K2CO3, and a cryogel is formed at about 0.5M K2CO3 concentration. The thermal stability of gel (5% SA+0.5M K2CO3) decreases with increase in surfactant concentration, a minimum is observed with increase in 16-4-16 concentration. The impact of surfactant addition on the alginate structure vis-à-vis its drug loading capability and release thereof was studied using Ibuprofen (IBU) as the model drug. The hydrogel with 16-4-16 exhibits higher IBU encapsulation and faster release in comparison to the one containing CTAB. This higher encapsulation-cum-faster release capability has been related to micelle mediated solubilization and greater porosity of the hydrogel with gemini surfactant.

Impact of Surfactant Addition on Oxygen Mass Transfer in a Bubble Column

AbstractThe following text is an additional technical note for: Impact of Surfactant Addition on Oxygen Mass Transfer in a Bubble Column by Dale D. McClure, Ai Chia Lee, John M. Kavanagh, David F. Fletcher, and Geoffrey W. BartonChem. Eng. Technol. 2015, 38 (1), 44–52. DOI: 10.1002/ceat.201400403.

Impact of Surfactant Addition on Oxygen Mass Transfer in a Bubble Column

AbstractThe impact of sparger design and surfactant addition on the oxygen transfer rate in a bubble column was examined. Additionally, measurements were also made of the holdup and bubble size distribution, allowing both the interfacial area for mass transfer and the liquid film mass transfer coefficient to be determined for a range of industrially relevant superficial velocities. It was found that for the velocity range examined changes in the superficial velocity had a minimal impact on the observed value of liquid film mass transfer coefficient. In contrast, addition of both hydrophilic and hydrophobic surface‐active compounds led to an approximately threefold reduction in liquid film mass transfer coefficient.

Improving Selectivity on Germanium CMP Applications

In the presented paper, the adsorption characteristics of cationic and anionic surfactants on germanium and silica were studied in order to improve selectivity in germanium based shallow trench isolation chemical mechanical planarization applications. It was observed that the very strong or loose self-assembled surfactant structures can help obtain selectivity on the silica/germanium systems. Simultaneously, good defectivity control with a sufficient material removal rate was obtained. The surface charges manipulated by the surfactant adsorption and the hydrophobic nature of the germanium surface were main criteria on the selection of the proper surfactant/oxidizer system. In addition, impact of surfactant addition on particle-particle interactions controlling slurry stability was also investigated in the paper.

Impact of Surfactant Chemistry on Bubble Column Systems

AbstractThe impact of surfactant addition on the overall holdup, drag coefficient, and bubble size distribution (BSD) in a bubble column operating at industrially relevant superficial velocities was analyzed. A range of surfactants was examined, including alcohols, sugars, and antifoaming agents. It was ascertained that the effect of a surfactant on the holdup and BSD could be related to the chemical structure of the compound, specifically its hydrophilic/hydrophobic nature as characterized by the octanol/water partition coefficient. Addition of 2‐propanol to an air/water system induces a behavior similar to the fermentation media used in aerobic bioprocesses, meaning that such a system can be applied as a meaningful physical analogue in pilot‐scale experimentation.