scholarly journals Enhanced removal of refractory pollutant from aniline aerofloat wastewater using combined vacuum ultraviolet and ozone (VUV/O3) process

2019 ◽  
Vol 80 (12) ◽  
pp. 2250-2259
Author(s):  
Xiaoyu Deng ◽  
Dachao Zhang ◽  
Meng Wu ◽  
Philip Antwi ◽  
Hao Su ◽  
...  
Keyword(s):  
Reaction Time ◽  
Degradation Rate ◽  
Vacuum Ultraviolet ◽  
Degradation Kinetics ◽  
Environmental Risks ◽  
Pollutant Degradation ◽  
Elimination Kinetics ◽  
First Order ◽  
Kinetics Of ◽  
Coexisting Ions

Abstract Aerofloats, such as aniline aerofloat ((C6H5NH)2PSSH), are extensively employed for collection activities in wastewater particularly in cases where minerals are in flotation. Although this aniline aerofloat has efficient collection properties, they are ordinarily biologically persistent chemicals in which case their residual, as well as their byproducts, pose great environmental risks to water and soils. In this study, the removal efficiency of aniline aerofloat (AAF) by a combined vacuum ultraviolet (VUV) and ozone (O3) process (VUV/O3) was evaluated. Furthermore, the impacts of pH, O3, the concentration of AAF and coexisting ions (SiO32−, CO32−, Cl− (Na+), SO42−, Ca2+) were systematically studied. The experiments revealed that, with an initial AAF of 15 mg/L, AAF removal >88% was feasible with a reaction time of 60 min, pH of 8 and O3 of 6 g/h. The order of influence of the selected coexisting ions on the degradation of AAF by VUV/O3 was Ca2+ > CO32− > SiO32− > Cl− (Na+) >SO42−. Compared with VUV and O3 in terms of pollutant degradation rate, VUV/O3 showed a remarkable performance, followed by O3 and VUV. Additionally, the degradation kinetics of AAF by the VUV/O3 process agreed well with first-order elimination kinetics.

Degradation Kinetics of Reactive Brilliant Red X-3B Dye by UV/Mn2+/H2O2/Micro-Aeration

2012 ◽  
Vol 441 ◽  
pp. 549-554
Author(s):  
Ying Jie Cai ◽  
Xiao Jun Yang ◽  
Dong Sheng Xia ◽  
Qing Fu Zeng
Keyword(s):  
Degradation Rate ◽  
Ph Value ◽  
Degradation Kinetics ◽  
H2o2 Concentration ◽  
Kinetics Equation ◽  
Linear Least Squares ◽  
First Order ◽  
First Order Kinetics ◽  
Pseudo First Order ◽  
Kinetics Of

Abstract. Degradation of reactive brilliant red X-3B (X-3B) by a UV/Mn2+/H2O2/micro- aeration method was investigated. The influencing factors of degradation of X-3B including UV irradiation, aeration, pH value, H2O2 concentration and X-3B concentration were examined. The results show that X-3B was effectively degraded by the UV/Mn2+/H2O2/micro-aeration method. The degradation rate of X-3B was obtained from weighted linear least squares analysis of the experimental data, and accorded with the pseudo-first order kinetics equation.

Degradation of biotansformation products of nonylphenol ethoxylates by ozonation and UV/TiO2 treatment

2002 ◽  
Vol 46 (11-12) ◽  
pp. 127-132 ◽  
Author(s):  
M. Ike ◽  
M. Asano ◽  
F.D. Belkada ◽  
S. Tsunoi ◽  
M. Tanaka ◽  
...  
Keyword(s):  
Degradation Rate ◽  
Degradation Kinetics ◽  
Chemical Oxidation ◽  
Order Kinetic ◽  
Oxidation Processes ◽  
First Order ◽  
First Order Kinetics ◽  
Biotransformation Products ◽  
Kinetics Of ◽  
Dioxide Suspension

The degradation kinetics of biotransformation products of nonylphenol polyethoxylates (NPEOs), nonylphenol (NP), nonylphenol monoethoxylate (NP1EO) and nonylphenoxy carboxylic acid (NP1EC), by ozonation and UV/TiO2 (ultraviolet photocatalytic degradation in the presence of titanium dioxide suspension as a catalyst) were investigated using lab-scale reactors. The degradation rate of NP by UV/TiO2 was the highest among the tested NPEOs metabolites, while NP1EC showed the lowest degradation rate. In contrast, ozonation was especially effective for the breakdown of NP1EC. NP could be also degraded efficiently by ozonation, however, it was much less effective for NP1EO decomposition. Degradation of NP by both chemical oxidation processes followed first-order kinetics. The degradation curves of NP1EO and NP1EC could be approximately described by first-order kinetics also, although the degradation of NP1EC by ozonation seemed to follow a second-order kinetic.

scholarly journals In situ degradability of dry matter and fibrous fraction of sorghum silage

2016 ◽  
Vol 38 (2) ◽  
pp. 171 ◽  
Author(s):  
Renê Ferreira Costa ◽  
Daniel Ananias de Assis Pires ◽  
Marielly Maria Almeida Moura ◽  
José Avelino Santos Rodrigues ◽  
Vicente Ribeiro Rocha Júnior ◽  
...  
Keyword(s):  
Experimental Design ◽  
Dry Matter ◽  
Degradation Rate ◽  
Degradation Kinetics ◽  
Grain Sorghum ◽  
Dual Purpose ◽  
Ruminal Degradability ◽  
Sorghum Silage ◽  
Kinetics Of

This study aimed to evaluate in situ degradability and degradation kinetics of DM, NDF and ADF of silage, with or without tannin in the grains. Two isogenic lines of grain sorghum (CMS-XS 114 with tannin and CMS-XS 165 without tannin) and two sorghum hybrids (BR-700 dual purpose with tannin and BR-601 forage without tannin) were ensiled; dried and ground silage samples were placed in nylon bags and introduced through the fistulas. After incubation for 6, 12, 24, 48, 72 and 96 hours, bags were taken for subsequent analysis of fibrous fractions. The experimental design was completely randomized with 4 replicates and 4 treatments and means compared by Tukey’s test at 5% probability. As for the DM degradation rate, silage of CMSXS165without tannin was superior. Silages of genotypes BR700 and CMSXS 114 with tannin showed the highest values of indigestible ADF (59.54 and 43.09%). Regarding the NDF, the potential degradation of silage of CMSXS165 line without tannin was superior. Tannin can reduce ruminal degradability of the dry matter and fibrous fractions. 

The Characteristics and Kinetic Equation of 4-CP Biodegradation by Fusarium sp. HJ01

2012 ◽  
Vol 554-556 ◽  
pp. 1925-1928 ◽  
Author(s):  
Ji Wu Li ◽  
Xiao Hong Zhu ◽  
Jun Ya Pan
Keyword(s):  
Carbon Source ◽  
Sole Carbon Source ◽  
Degradation Rate ◽  
Order Equation ◽  
First Order ◽  
Haldane Model ◽  
Effects Of Ph ◽  
Fusarium Sp ◽  
Ph Range ◽  
Kinetics Of

The stain of Fusarium sp. HJ01 used in 4-chlorophenol (4-CP) degradation was isolated in our laboratory. The effects of pH, temperature, 4-CP concentration, carbon source on 4-CP degradation rate were studied. It was concluded that Fusarium sp. HJ01 could grow with 4-CP as the sole carbon and energy source. 4-CP concentration of 100mg/L in the pH range of 4~10 and temperature range of 25°C~35°C could be degraded completely. The capacity of 4-CP degradation was effectively enhanced by the addiction of sucrose. The kinetics of 4-CP degradation could well accord with the Haldane model for 4-CP as the sole carbon source and with first order equation for added other sucrose.

scholarly journals PERSISTENCIA DEL ENDOSULFÁN EN MEDIO ACUOSO ESTÁTICO

2001 ◽  
Vol 11 ◽  
Author(s):  
ARGELIA M. L. LENARDÓN ◽  
PATRICIA M. DE LA SIERRA ◽  
FERNANDA MARINO
Keyword(s):  
River Water ◽  
Degradation Kinetics ◽  
Water Type ◽  
Ultrapure Water ◽  
First Order ◽  
First Order Kinetics ◽  
Predominant Factor ◽  
Two Temperatures ◽  
In The Beginning ◽  
Kinetics Of

Estudou-se a cinética de degradação da mistura dos isômeros alfa e beta Endosulfan em diferentes condições de trabalho. Os compostos foram adicionados em água ultrapura, água do rio, água de rio filtrada e água ultrapura com sais (salinidade similar à agua do rio utilizada). As condições de degradação escolhidas foram: escuridão e duas temperaturas (14+1 ºC e 26+1 ºC). As amostragens foram programadas de modo a se obter dados periódicos mais freqüentes no início da experiência e posteriormente mais espaçados até o seu final (230 dias). As amostras foram submetidas à microextração e analisadas por cromatografia em fase gasosa com detector de Ni63 e coluna Megabore DB-5. A degradação foi descrita de acordo com a cinética de primeira ordem, determinando-se os tempos de meia vida (t1/2) e as energias de ativação (Ea). Os dados obtidos evidenciaram que a temperatura é o fator preponderante, sendo possível deduzir que o alfaendosulfan, exceto para água ultrapura (AU), é mais influenciado pela temperatura do que o beta-endosulfan. O segundo efeito mais importante refere-se ao tipo de água utilizada como matriz, devido à influência da salinidade. PERSISTANCE OF ENDOSULFAN IN STATIC AQUEOUS MEDIUM Abstract Degradation kinetics of a mixture of alpha- and beta-Endosulfan isomers was studied under different conditions. The compounds were spiked in ultrapure water, river water, filtered water and ultrapure water with salts (similar salinity condition to that of the river water used). The degradation conditions chosen were: darkness, two temperatures (14+1 ºC e 26+1 ºC). Samplings were programmed in order to obtain more frequent periodical data in the beginning of the experience and after more spaced until its end (230 days). The samples were submitted to microextraction and then analyzed by gas chromatography through a Ni63 detector equipped with a Megabore DB-5 column. Degradation was described using first-order kinetics to determine half-life times (t1/2) and activation energies (Ea). The data obtained evidenced that temperature is the predominant factor, it can possibly be inferred that alfa-endosulfan is much more influenced than beta-endosulfan except for ultrapure water (UW). The second important effect is the water type used as matrix, due to the influence of salinity.

scholarly journals Nitrogen degradation of the limestone-urea mixtures in the rumen of goats

2018 ◽  
Vol 43 (3) ◽  
pp. 282
Author(s):  
M. A. Harahap ◽  
L. K. Nuswantara ◽  
E. Pangestu ◽  
F. Wahyono ◽  
J. Achmadi
Keyword(s):  
Dietary Supplement ◽  
Dry Matter ◽  
Degradation Rate ◽  
Slow Release ◽  
Soluble Fraction ◽  
Degradation Kinetics ◽  
Central Java ◽  
Ruminal Degradation ◽  
Kinetics Of ◽  
Central Java Province

This experiment was aimed to study the degradation kinetics of limestone-urea mixtures in the goats rumen using the nylon bag technique. Samples of limestone were obtained from two limestone mountains, Pamotan Subdistrict of Central Java Province and Wonosari Subdistrict of Yogyakarta Province. The mixtures were created by combining urea at levels 25, 50, 75and 100%; respectively with two limestones on the basis of their Ca contents: L0U100, LP25U75, LP50U50; LP75U25, LW25U75; LW50U50; and LW75U25. The soluble fraction, potentially degradable fraction, the degradation rate of potentially degradable fraction, and effective degradation of respective dry matter (DM) and nitrogen (N) ruminal degradation kinetics were measured in each mixture. The mixture of LP75U25 had lowest effective and degradation rate of potentially degradable fraction (P<0.05) respectively for DM and N compared with those of other mixtures. In conclusion, the limestone-urea mixture of LP75U25 could be suggested as a dietary supplement of ruminal N slow release.

The In Vitro Degradation Kinetics of Polyurethane Prodrug Materials

2011 ◽  
Vol 399-401 ◽  
pp. 1067-1070
Author(s):  
Chun Yan Li ◽  
Cong Cong Hu ◽  
Zhi Guo Wen ◽  
Sheng Xiong Dong
Keyword(s):  
Drug Release ◽  
High Performance ◽  
Degradation Kinetics ◽  
Hplc Method ◽  
In Vitro Degradation ◽  
Erosion Mechanism ◽  
First Order ◽  
First Order Kinetics ◽  
Kinetics Of

The method of high performance liquid chromatography (HPLC) is established to determine the content of antibacterial agent — ciprofloxacin (CF) in the degradation solution of ciprofloxacin-polyurethane (CFPU) and investigate the in vitro degradation kinetics by plotting and fitting the cumulative release curves to inspect the effects of different medium and different concentrations on drug release. The results showed that the HPLC method is accurate, reliable and simple. The drug-release of CFPU was bioresponsive and could be accorded with first order kinetics. It was observed that CF was released from CFPU by a combination of diffusion and erosion mechanism, mainly in the manner of diffusion in the absence of infection while erosion mechanism in the presence of infection.

Degradation of azo dye with dirhodium(II) caprolactamate as heterogeneous catalyst

2012 ◽  
Vol 65 (12) ◽  
pp. 2175-2182
Author(s):  
Abeer S. Elsherbiny ◽  
Sahar H. El-Khalafy ◽  
Michael P. Doyle
Keyword(s):  
Hydroxyl Radicals ◽  
Azo Dye ◽  
Degradation Kinetics ◽  
Oxidative Degradation ◽  
Total Carbon ◽  
Order Kinetic ◽  
First Order ◽  
Pseudo First Order ◽  
Kinetics Of ◽  
Degradation Of Azo Dye

The kinetics of the oxidative degradation of an azo dye Metanil Yellow (MY) was investigated in aqueous solution using dirhodium(II) caprolactamate, Rh2(cap)4, as a catalyst in the presence of H2O2 as oxidizing agent. The reaction process was followed by UV/Vis spectrophotometer. The decolorization and degradation kinetics were investigated and both followed a pseudo-first-order kinetic with respect to the [MY]. The effects of various parameters such as H2O2 and dye concentrations, the amount of catalyst and temperature have been studied. The studies show that Rh2(cap)4 is a very effective catalyst for the formation of hydroxyl radicals HO• which oxidized and degraded about 92% of MY into CO2 and H2O after 24 h as measured by total carbon analyzer.

scholarly journals Highly efficient UV/H2O2 technology for the removal of nifedipine antibiotics: Kinetics, co-existing anions and degradation pathways

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258483
Author(s):  
Wenping Dong ◽  
Chuanxi Yang ◽  
Lingli Zhang ◽  
Qiang Su ◽  
Xiaofeng Zou ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Hydrogen Peroxide ◽  
Degradation Rate ◽  
Degradation Kinetics ◽  
Degradation Pathways ◽  
Oxygen Species ◽  
Highly Efficient ◽  
Initial Ph ◽  
Primary Key ◽  
Kinetics Of

This study investigates the degradation of nifedipine (NIF) by using a novel and highly efficient ultraviolet light combined with hydrogen peroxide (UV/H2O2). The degradation rate and degradation kinetics of NIF first increased and then remained constant as the H2O2 dose increased, and the quasi-percolation threshold was an H2O2 dose of 0.378 mmol/L. An increase in the initial pH and divalent anions (SO42- and CO32-) resulted in a linear decrease of NIF (the R2 of the initial pH, SO42- and CO32- was 0.6884, 0.9939 and 0.8589, respectively). The effect of monovalent anions was complex; Cl- and NO3- had opposite effects: low Cl- or high NO3- promoted degradation, and high Cl- or low NO3- inhibited the degradation of NIF. The degradation rate and kinetics constant of NIF via UV/H2O2 were 99.94% and 1.45569 min-1, respectively, and the NIF concentration = 5 mg/L, pH = 7, the H2O2 dose = 0.52 mmol/L, T = 20 ℃ and the reaction time = 5 min. The ·OH was the primary key reactive oxygen species (ROS) and ·O2- was the secondary key ROS. There were 11 intermediate products (P345, P329, P329-2, P315, P301, P274, P271, P241, P200, P181 and P158) and 2 degradation pathways (dehydrogenation of NIF → P345 → P274 and dehydration of NIF → P329 → P315).

scholarly journals Thermal Degradation Kinetics of Capsaicin on Blanching-Brine-Calcium Pretreatment Red Chili Pepper Drying

2018 ◽  
Vol 13 (2) ◽  
pp. 365 ◽  
Author(s):  
Uma Fadzilia Arifin ◽  
Mohamad Djaeni
Keyword(s):  
Thermal Degradation ◽  
Degradation Rate ◽  
Degradation Kinetics ◽  
Bioactive Compound ◽  
Chili Pepper ◽  
Thermal Degradation Kinetics ◽  
Drying Process ◽  
Local Farmer ◽  
Layer Chromatography ◽  
Kinetics Of

Post-harvest red chili pepper (Capsicum frutescens) has highly capsaicin as bioactive compound and moisture content. However, capsaicin is the responsible bioactive compound in chili for hot sensation that easy to degrade by partial oxidation caused introduction of heat in drying process. The objective of this research was to investigate kinetics of capsaicin degradation in the drying process under blanching-brine-calcium pretreatment and various temperatures. For this purposes, chili provided local farmer was pretreated using blanching-brine-calcium pretreatment. Afterward, they were dried at 40, 50, 60, and 70 oC for 8 hours. Degradation of capsaicin content was observed every 2 hours using Thin Layer Chromatography (TLC). Results showed kinetics of capsaicin degradation was categorized as second order reaction. At the same temperature and time, capsaicin retention of blanching-brine-calcium pretreated chili has highest value. The temperature dependence of the capsaicin degradation rate was analyzed using Arrhenius correlation. The activation energy for degradation rate of capsaicin during drying was around 45.10367 kJ/mol.K. It indicated the degradation rate increased as well as increased the temperature at the same time. Copyright © 2018 BCREC Group. All rights reservedReceived: 26th October 2017; Revised: 14th February 2018; Accepted: 18th February 2018; Available online: 11st June 2018; Published regularly: 1st August 2018How to Cite: Arifin, U.F., Djaeni, M. (2018). Thermal Degradation Kinetics of Capsaicin on Blanching-Brine-Calcium Pretreatment Red Chili Pepper Drying. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (2): 365-372 (doi:10.9767/bcrec.13.2.1660.365-372) 

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