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Zhao S.,Harbin Institute of Technology | Wang P.,Harbin Institute of Technology | Wang C.,Harbin Institute of Technology | Langer J.L.,Serionix Inc. | And 2 more authors.
Chemical Engineering Journal | Year: 2013

The purification and reclaiming of synthetic and industrial high temperature condensed water containing excess oil and iron is investigated in this study using thermostable poly(phthalazine ether sulfone ketone) (PPESK) ultrafiltration membranes. The results show operation parameters such as transmembrane pressure, temperature and pH of feed solution, initial oil and iron concentration each play important roles in the permeate flux and oil/iron removal efficiencies. Membrane performance is almost recovered after washing with a combination of NaOH and ethanol. High temperature condensed water from Daqing petroleum refinery can be consecutively purified using a PPESK ultrafiltration membrane. The turbidity of the solutions is almost removed. Oil and iron concentrations in the permeate solutions are below 1. mg/L and 50. μg/L, respectively, which satisfy the Quality Criterion of Water and Steam for Steam Power Equipment in China. UF process shows a promising alternative to existing technology in the Daqing petroleum refinery in terms of cost and environmental protection as well as energy recovery. For future possible combination of UF and NF process application, both economic cost and saving are evaluated, and the breakeven time is about 11. months. © 2013 Elsevier B.V. Source

Langer J.L.,University of Illinois at Urbana - Champaign | Langer J.L.,Serionix Inc. | Economy J.,University of Illinois at Urbana - Champaign | Cahill D.G.,University of Illinois at Urbana - Champaign
ACS Macro Letters | Year: 2012

The exchange of one counterion with another, perchlorate with chloride, induces mechanical stress in polycation matrices. The magnitude of the stress decreases with increasing hydrophobicity of the matrix. Thin films of cross-linked poly-(vinylbenzyl chloride) are reacted with trialkylamines to give immobilized poly(vinylbenzyltrialkylammonium chloride) matrices. Mechanical stress in films is measured using a scanning laser apparatus. Each material exhibits tension upon exchange from chloride to perchlorate form, consistent with matrix dehydration. Data are fit to a chemical equilibrium model assuming proportionality between stress and conversion to perchlorate form. Maximum changes in biaxial stress range from 3.1 MPa for a tributylamine-modified film to 16.6 MPa for a trimethylaminemodified film. Selectivity coefficients range from 43 for the trimethylamine-modified film to 370 and 450 for the tributylamineand tripropylamine-modified films, respectively, indicating greater selectivity for perchlorate in more hydrophobic matrices. These results help clarify the physical origins of perchlorate selectivity in anion-exchange resins. © 2012 American Chemical Society. Source

Langer J.L.,University of Illinois at Urbana - Champaign | Langer J.L.,Serionix Inc. | Economy J.,University of Illinois at Urbana - Champaign | Cahill D.G.,University of Illinois at Urbana - Champaign
Macromolecules | Year: 2012

Absorption of water in cationic polyelectrolyte thin films is investigated by measuring mass uptake and mechanical stress using a quartz crystal microbalance and scanning optical laser apparatus, respectively. Thin layers of poly(vinylbenzyl chloride) and diazabicyclo[2.2.2]octane are spin-cast onto quartz crystal sensors or cover glasses. Films are subsequently cured and reacted by nucleophilic substitution with trimethylamine, triethylamine, tripropylamine, or tributylamine to give an immobilized poly(vinylbenzyltrialkylammonium chloride) matrix. Water absorption in these films depends strongly on both the amine modifier and counterion present in the matrix. Mass uptake ranges from 5.7% for a tributylamine-modified film in perchlorate form to 52% for a trimethylamine-modified film in fluoride form. This water uptake results in a maximum relative compressive biaxial stress of -33 and -113 MPa for these two films, respectively. Mass uptake and biaxial stress data give evidence of yielding upon hydration and dehydration. The yielding is attributed to elasto-viscoplastic deformation and influenced by a depression of the glass transition temperature via plasticizing. The Young's modulus (Y f) of the unmodified film is measured from biaxial stress and ellipsometric thickness to be 3.9 GPa, consistent with structurally related polystyrene and slightly lower than Y f = 5.0 GPa as measured acoustically. These results support the prevailing theory relating selectivity and diffusion in perchlorate-selective anion-exchange resins to hydrophilicity and water content and also suggest the mechanical properties of hydrophobic polycations may be effectively controlled through judicious selection of fixed ion and counterion. © 2012 American Chemical Society. Source

Luo H.,Shanghai JiaoTong University | Gu C.,Shanghai JiaoTong University | Zheng W.,Serionix Inc. | Dai F.,Shanghai JiaoTong University | And 2 more authors.
RSC Advances | Year: 2015

Silver nanoparticles have been proven to exhibit excellent antimicrobial activity, but problems such as aggregation and toxicity limit their practical application. To solve these problems, a kind of sub-micrometer poly-dopamine spheres loaded with silver nanoparticles (Ag@PDS) were fabricated using a facile method. Silver nitrate was reduced by poly-dopamine spheres (PDS) without surface modification, and no other reducing agent added. This entire preparation process is very green, simple and efficient. As a result, Ag NPs have been fixed and uniformly dispersed onto the surface of the PDS, which can effectively prevent Ag NPs from aggregating or oxidizing during their application. Because the size of the uniform hybrid sphere is easily controlled by adjusting the ratio of ammonia to dopamine, it is convenient to fabricate hybrid spheres with desired sizes. These hybrids are capable of completely inhibiting bacterial growth because of their excellent antibacterial properties. Finally, the prospect of the organismal level impact of the Ag@PDS hybrid has also been proposed. This journal is © The Royal Society of Chemistry. Source

Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase I | Award Amount: 149.98K | Year: 2012

Volatile organic compounds (VOCs) and toxic industrial chemicals (TICs) both pose a significant threat to DoD personnel both in the field as well as in established infrastructure such as large buildings. Current VOC/TIC protection technologies suffer from incomplete removal of contaminants, high operating costs, and limitation to single-use only. Recent research suggests activated carbon fibers (ACFs) are an optimal platform for continuous chemical protection due to high capacity and rapid rates of adsorption and desorption. Traditional ACFs unfortunately suffer from exorbitant costs. This SBIR Phase I project will result in the development of ultrafast, high permeability, regenerable ACFs based on a low-cost carbon-on-glass geometry. Serionix will demonstrate feasibility of this new technology through the following activities: 1) preparation of ACFs using a dip-coating method; 2)characterization of tunable TIC (ammonia, NO2) adsorption capability of the ACFs; 3) research and development of new synthesis and regeneration techniques to maximize the efficiency of the system.

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