Synthesis of phosphomolybdic acid/nanocrystalline titanium silicalite-1 catalyst in the presence of hydrogen peroxide for effective adsorption-oxidative desulfurization

The phosphomolybdic acid (HPMo) supported on microporous nanocrystalline titanium silicalite-1 zeolite (Nano-TS-1) catalysts were prepared in the absence or presence of hydrogen peroxide via the impregnation method. The catalysts were...

Determination of moxifloxacin hydrochloride in AVELOX pharmacological formulations using modified potentiometer sensors

Three different carbon paste (CP), silk-screen (SP) and poly (vinyl chloride) (PVC) modified electrodes were obtained to verify the reliability of AVELOX, the generic name of which is Moxifloxacin HCl (AV-MOXH). The sensing membranes were containing AVELOX ion associated complexes with sodium tetraphenylborate (NaTPB), phosphomolybdic acid (PMA), phosphotungstic acid (PTA), and ammonium reineckate (RN) as electroactive materials. All three electrodes gave fast, viable, and near-Nernstian linear responses over a relative wide concentration range that ranged from 1.010-6 to 1.010-2 mol / L AV-MOXH at 25° C with a monovalent cationic decrease. The sensors demonstrated a good discernment of AV-MOXH from numerous inorganic and organic compounds such as glucose, sucrose, Na+, Ca+, etc. Additionally, the isothermal coefficients along with selectivity coefficients were calculated. The modified Screen Printed Electrode sensor appeared to be highly sensitive for the determination of AV-MOXH. The electrode response was observed in pH range 2--6 for ISPE electrodes and IPVC electrodes and 3--7 for ICPE electrodes under various temperature conditions. The short response time, lifetime validity, recovery, and all the methods of validation such as limit of detection and limit of quantification were estimated. The potentiometric method turned out to be suitable for determining AV-MOXH in pharmacological formulations, and the findings obtained are comparable to the “HPLC official method” in terms of the agreement. As a result, the postulated potentiometric approach was verified in accordance with IUPAC guidelines.

Fabrication of Polyelectrolyte Membranes of Pectin Graft-Copolymers with PVA and Their Composites with Phosphomolybdic Acid for Drug Delivery, Toxic Metal Ion Removal, and Fuel Cell Applications

In this study, a simple method for the fabrication of highly diffusive, adsorptive and conductive eco-friendly polyelectrolyte membranes (PEMs) with sulfonate functionalized pectin and poly(vinyl alcohol)(PVA) was established. The graft-copolymers were synthesized by employing the use of potassium persulfate as a free radical initiator from pectin (PC), a carbohydrate polymer with 2-acrylamido-2-methyl-1-propanesulphonic acid (AMPS) and sodium 4-vinylbenzene sulphonate (SVBS). The PEMs were fabricated from the blends of pectin graft-copolymers (PC-g-AMPS and PC-g-SVBS) and PVA by using a solution casting method, followed by chemical crosslinking with glutaraldehyde. The composite PEMs were fabricated by mixing phosphomolybdic acid with the aforementioned blends. The PEMs were successfully characterized by FTIR, XRD, SEM, and EDAX studies. They were assessed for the controlled release of an anti-cancer drug (5-fluorouracil) and the removal of toxic metal ions (Cu2+) from aqueous media. Furthermore, the composite PEMs were evaluated for fuel cell application. The 5-fluorouracil release capacity of the PEMs was found to be 93% and 99.1% at 300 min in a phosphate buffer solution (pH = 7.4). The highest Cu2+ removal was observed at 206.7 and 190.1 mg/g. The phosphomolybdic acid-embedded PEMs showed superior methanol permeability, i.e., 6.83 × 10−5, and 5.94 × 10−5, compared to the pristine PEMs. Furthermore, the same trend was observed for the proton conductivities, i.e., 13.77 × 10−3, and 18.6 × 10−3 S/cm at 30 °C.

Facile One-step Preparation of Mesoporous Siliceous phophsomolybdic acid for Proton Exchange Membrane

Background: Proton exchange membrane is art of PEM fuel cells, developing active materials with robust structure and high proton conductivity has attained huge attention in recent decade amongst researchers. Aims/objectives: Here we have developed a novel approach to prepare a siliceous mesoporous heteropoly acid with high stability in polar media and high proton conductivity to be utilized as proton exchange membrane. Methods: A highly stable mesoporous siliceous phosphomolybdic acid has been synthesized via a simple self-assembly between phosphomolybdic acid (PMA), the polymeric surfactant, and the silica precursor stabilized by KCl molecules as a proton conducting material for proton exchange membrane application. Results: As prepared siliceous mesoporous phosphomolybdic acids (mPMA-Si) show a high surface area with a highly crystalline structure, however the crystallinity reduced by increasing the silica content. Further analysis proved the Keggin structure remain intact in final materials. mPMA-8 Si shows the highest performance among all the materials studied with proton conductivity of 0.263 S.cm-1 at 70 oC. Conclusion: As prepared mPMA-xSi has shown a very high proton conductivity in a range of temperatures which make them a promising material for proton exchange membrane.