Activation of water in the downstream of low-pressure ammonia plasma discharge

Pandey²,

Patel³

et al. 2023

Preprint

The dye degradation efficacy of the cold plasma pencil jet is presented in the present investigation. Air plasma is produced in the cylindrical coaxial dielectric barrier discharge configuration. Electrical characterization of plasma is performed and the plasma species are identified using optical emission spectroscopy. For the dye degradation study using air plasma, six different types of dyes (erythrosine, metanil yellow, sudan I, crystal violet, rhodamine B, and Indigo) are chosen. The degradation of dyes is analyzed using UV visible spectroscopy, total organic carbon, and chemical oxygen demand. The results showed complete degradation of all the dyes in UV visible analysis with minimum time for indigo (3 minutes) and maximum time for erythrosine (45 minutes). Moreover, erythrosine (k = 1.08 mg L-1 min-1) and sudan I (k= 3.46 mg L-1 min-1) follows zero-order degradation kinetic and metanil yellow (k = 0.094 min-1), crystal violet (k = 0.25 min-1), rhodamine B (k = 0.17 min-1), Indigo (k = 0.81 min-1) follows first-order degradation kinetics. Also, substantial enhancement in mineralization and reduction in chemical oxygen demand of all the dyes occurs after plasma treatment. The toxicity of plasma degraded dye solution toward freshwater algae species (Chlorella Sorokiniana and Chlorella Pyrenoidosa) are significantly low compared to virgin dyes solutions. The study reveals that pencil plasma jet substantially degrade dyes as well as converts the dyes solutions non-toxic.

Section: Physicochemical Properties and Reactive Oxygen-nitrogen Spec...mentioning

confidence: 94%

Dyes degradation using atmospheric pressure dielectric barrier discharge pencil plasma jet

Pandey²,

Patel³

et al. 2023

Preprint

“…This NT-PPJ setup was powered with a high voltage fixed-frequency power supply (Vmax -10 kV, f = 50 Hz). The voltage drop across the NT-PPJ setup and total current were measured using a 1000x voltage probe, a Rogowski coil, and an oscilloscope (for more detail, see supplementary material Table S1) (40)(41)(42). The species/radicals formed during air discharge in the NT-PPJ setup were identified by recording the optical emission spectra of air plasma using an optical fiber and spectrophotometers (maker StellarNet Inc. model no.…”

Section: Methodsmentioning

confidence: 99%

Methotrexate degradation in artificial wastewater using non-thermal pencil plasma jet

2023

Preprint

The rising global cancer rate is driving up the consumption of anticancer drugs. This causing a noticeable increase in the levels of these drugs in wastewater. The drugs are not metabolized effectively by the human body, leading to their presence in human waste, as well as in the effluent from hospitals and drug manufacturing industries. Methotrexate is a commonly used drug for treating various types of cancer. Its complex organic structure makes it difficult to degrade using conventional methods. The present work proposed a non-thermal pencil plasma jet treatment for methotrexate degradation. The air plasma produced in this jet setup is electrical characterized and plasma species/radicals are identified using emission spectroscopy. The degradation of drug is monitored by studying the change in solution physiochemical properties, HPLC-UV analysis, and removal of total organic carbon, etc. Results show that a 9-minute plasma treatment completely degraded the drug solution that followed first order degradation kinetics with rate constant 0.38 min-1 and 84.54% mineralization was observed. Additionally, an increase in electrical conductivity and dissolved solids compared to virgin water-plasma interaction indicated the formation of new, smaller compounds (2,4-Diaminopteridine-6-carboxylic acid, N-(4-Aminobenzoyl)-L-glutamic acid, etc.) after drug degradation. The plasma-treated methotrexate solution also showed lower toxicity towards freshwater chlorella algae compared to the untreated solution. Finally, it can be said that non-thermal plasma jets are economically and environmentally friendly devices that have the potential to be used for the treatment of complex and resistive anticancer drugpolluted wastewaters.

“…The NT-PPJ is powered with a 50 Hz, 10 kV high voltage rating alternating current (AC) power supply. The voltage and current during the air discharge (or air plasma formation) were measured using a 1000x voltage probe (Tektronix-P6015A) and a rogowski coil (current transformer (1V/1A), CM-100-MG, Ion Physics Corporation) connect to an oscilloscope (Tektronix-TDS2014C) (29). The air emission spectra in the afterglow region were captured using optical fiber and spectrophotometers (Model EPP2000-UV from StellarNet Inc. and UVH-1 from ASEQ instruments) in the range of 190 nm and 900 nm (16,30).…”

Section: Methodsmentioning

confidence: 99%

Penicillin Antibiotic (Ampicillin and Cloxacillin) Degradation Using Non-Thermal Pencil Plasma Jet

2023

Preprint

In the present work an antibiotic drug degradation efficacy of a non-thermal pencil plasma jet in artificial wastewater. Air is used as a plasma-forming gas. The air plasma is produced in a cylindrical co-axial assembly of electrodes powered by a 50 Hz High-voltage power supply. The electrical characterization of plasma is performed and the generated plasma species/radicals are identified using optical emission spectroscopy. The degradation of antibiotics in solution after plasma treatment is analyzed using high performance liquid chromatography with photodiode array detector (HPLC-PDA). In addition, total organic carbon (TOC), and chemical oxygen demand (COD) is also determined. The HPLC-PDA results reveal that plasma degradation of antibiotics solution followed first-order degradation kinetics with a rate constant of 0.158 min-1 (ampicillin) and 0.366 min-1 (Cloxacillin). Furthermore, the reduction in TOC and COD supported the degradation of antibiotics using plasma jet. It has been observed the plasma 9-minute gives 76.10% and 99.99% degradation in ampicillin and cloxacillin solution respectively. The change in physicochemical properties and various reactive species formed due to which degradation of antibiotics solution take place are measured. Finally, the toxicity of plasma degraded antibiotic solutions are studied on freshwater chlorella algae species. The results reveal that plasma degraded antibiotics solutions are non-toxic toward freshwater algae. The non-thermal plasma jet could be a potential eco-friendly alternative for the degradation of various antibiotic drugs present in wastewater.