scholarly journals Kinetics of Cu, Pb and Zn removal during soil flushing with washing agents derived from sewage sludge

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Barbara Klik ◽  
Zygmunt M. Gusiatin ◽  
Dorota Kulikowska

AbstractThis paper presents the first tests of Cu (7875 mg/kg), Pb (1414 mg/kg) and Zn (566 mg/kg) removal from contaminated soil with sewage-sludge–derived washing agents (SS_WAs) (dissolved organic matter, DOM; soluble humic-like substances, HLS; soluble humic substances, SHS) and Na2EDTA (as a standard benchmark) in column experiments. Flow rates of 0.5 ml/min and 1 ml/min were used. Using a 1. order kinetic model, the kinetic constant (k), the maximum concentrations of each metal removed (Cmax), and the initial rates of metal removal (r) were established. At both flow rates, stable flow velocity was maintained for approximately eight pore volumes, for flushing times of 8 h (1.0 ml/min) and 16 h (0.5 ml/min). Although the flow rate did not influence k, it influenced Cmax: at 1 ml/min, Cmax values were higher than at 0.5 ml/min. For Cu and Zn, but not Pb, k was about twofold higher with Na2EDTA than with SS_WAs. Although Na2EDTA gave the highest kCu, Cmax,Cu was highest with DOM (Na2EDTA, 66%; DOM 73%). For Pb removal, HLS was the most effective SS_WA (77%; Na2EDTA was 80% effective). kZn was about twofold higher with Na2EDTA than with SS_WAs. Cmax,Zn was highest with HLS. The quick mobilization of Cu, Pb and Zn with most of the WAs corresponded to efficient metal removal from the exchangeable (F1) fraction.

Author(s):  
Lieke Riadi ◽  
Theresia Desy Askitosari ◽  
Ragil Puspita Dutaning Widhi ◽  
Melvina Laurensia ◽  
Yuana Elly Agustin ◽  
...  

Abstract The microalga Arthrospira platensis (Spirulina) is used for tempeh wastewater treatment. The microalga growth and the kinetics of COD degradation under different light intensities (2,100 and 4,300 lux), tempeh wastewater concentrations (0, 0.5, 1, 1.5% v/v), and sodium nitrate concentrations (0, 0.75, 1, 2, 2.5 g/L) were studied. Improved cell growth in wastewater indicated that mixotrophic growth was preferred. The addition of sodium nitrate up to 2 g/L increased the COD removal. The highest COD removal was 92.2%. It was obtained from the cultivation with 1% v/v tempeh wastewater, 2 g/L sodium nitrate, 2,100 lux, and the specific growth rate of 0.33 ± 0.01 day−1. The COD removal followed a pseudo first – order kinetic model with the kinetic constant of 0.3748 day−1 and the nitrate uptake rate of 0.122 g/L-day. The results can be used to design a pilot – scale tempeh wastewater treatment facility using A. platensis for tertiary treatment. Based on the kinetic model, a 20 m3 reactor can treat tempeh wastewater to reduce the COD from 400 to 100 ppm in 4 days and produces approximately 32.8 kg of dried microalgae.


2012 ◽  
Vol 8 (3) ◽  
Author(s):  
Xiaoyan Dai ◽  
Chenhuan Yu ◽  
Qiaofeng Wu

Abstract Jiangpo is an increasingly popular East Asian spice which is made from Mangnolia officinalis bark and ginger juice. Since it induces bioactive compounds decomposition and has influence on final flavor and fragrance, cooking is regarded as the key operation in preparation of Jiangpo. To evaluate the bioactive compounds content changes of Jiangpo during thermal processing, kinetic parameters including reaction order, rate constant, T1/2 and activation energy of bioactive markers namely honokiol, magnolol and curcumin were determined. Cooking was set at temperatures 60, 90 and 120 °C for selected time intervals. Results displayed the thermal kinetic characteristics of the three compounds. Thermal degradation of Honokiol and magnolol both followed first order kinetic model and the loss of curcumin fitted second order. A mathematical model based on the obtained kinetic parameters has also been developed to predict the degradation of honokiol, magnolol and curcumin in non-isothermal state. All the information in this paper could contribute necessary information for optimizing the existing heat processing of Jiangpo.


Energies ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 5451
Author(s):  
Sylwia Stegenta-Dąbrowska ◽  
Karolina Sobieraj ◽  
Jacek A. Koziel ◽  
Jerzy Bieniek ◽  
Andrzej Białowiec

Knowledge of kinetic parameters of CO production during biowaste composting is significantly important for the prediction of its course and estimation of total gas quantity. This allows increasing the control of the process, to minimize its negative impact on the environment and to protect the occupational safety of employees exposed to CO in the biowaste composting plant. For the first time, a full study of the influence of temperature and biowaste sterilization on the kinetics of CO production is presented. The lab-scale experiments used a mixture of green waste, dairy cattle manure, and sawdust in two variants: sterilized and non-sterilized samples. The process was carried out in controlled temperature reactors with measuring the concentrations of CO, O2, and CO2 every 12 h.CO production and k value increased with temperature. However, higher CO production was observed in biotic conditions between 10~50 °C, suggesting the biotic CO formation and 1st-order kinetics. The abiotic (thermochemical) process was more efficiently generating CO above 50 °C, described with a 0-order kinetic model. Additionally, the rate constant (k) value of CO production under biotic conditions was increasing up to a temperature of 60 °C, above which a slight decrease in CO production rate was observed at 70 °C. The presented results are the basis for further studies focused on the feasibility of (1) the mitigation and (2) valorization of CO production during the biowaste biostabilization are warranted.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Diya'uddeen Basheer Hasan ◽  
Abdul Aziz Abdul Raman ◽  
Wan Mohd Ashri Wan Daud

The mineralisation kinetics of petroleum refinery effluent (PRE) by Fenton oxidation were evaluated. Within the ambit of the experimental data generated, first-order kinetic model (FKM), generalised lumped kinetic model (GLKM), and generalized kinetic model (GKM) were tested. The obtained apparent kinetic rate constants for the initial oxidation step (k2′), their final oxidation step (k1′), and the direct conversion to endproducts step (k3′) were 10.12, 3.78, and 0.24 min−1for GKM; 0.98, 0.98, and nil min−1for GLKM; and nil, nil, and >0.005 min−1for FKM. The findings showed that GKM is superior in estimating the mineralization kinetics.


Author(s):  
Thamer Abdul Kadir Khalil ◽  
Mazin Ibrahem Al-Zubaidy ◽  
Omer Fawzi Abdulaziz

Kinetics of browning color development, described as browning index (BI), of peach puree subjected to high hydrostatic pressure (HHP) treatments (400, 500, and 600 MPa/1 and 3 min) during 6 weeks of storage at 4 and 20°C were investigated. This research was conducted to modify the use of pressure scale instead of temperature scale in calculating the kinetic parameters of BI values in peach puree samples. The increase in BI values followed the zero-order kinetic model. The highest activation energy (Ea) was experienced with HHP treatment (400, 500, and 600 MPa/3 min) of peach puree samples stored at 4°C.


2013 ◽  
Vol 807-809 ◽  
pp. 478-485 ◽  
Author(s):  
Ting Li ◽  
Wen Yi Dong ◽  
Hong Jie Wang ◽  
Jin Nan Lin ◽  
Feng Ouyang ◽  
...  

In this study, the effect of operating parameters and the co-existing ions on the phosphate removal during the ferrous iron oxidation was investigated. Results showed that with the increase of DO and [Fe (II)]0, the final phosphate removal rate both increased. But with increasing of pH, the final phosphate removal rate firstly increased and then decreased when the pH was higher than 8.0. The co-existing ions affected the final removal rate significantly, and the kinetics of phosphate removal followed the pseudo-first-order kinetic model. The corresponding kobs trends for the cation followed the order of Cu2+>Mn2+>Zn2+>NH4+-N. The presence of Cu2+ promoted the phosphate removal significantly. Compared with the control, , the time required to achieve 40 % phosphate removal rate, at the condition of 0.5 mg/L Cu2+, reduced from 60 min to 10 s. However, the selective anions inhibited the phosphate removal, due to the formation of Fe-anions complexes. The effect of selective anions on the phosphate removal rate constant decreased in the order of SO42->Cl-> NO3-.


2015 ◽  
Vol 737 ◽  
pp. 537-540
Author(s):  
Yan Wei Guo ◽  
Hua Zhang ◽  
Zhi Liang Zhu

A novel Mg/Fe/Ce layered double hydroxide (LDHs) and its calcined product (CLDH) were synthesized and CLDH was used as adsorbents for the removal of chlorate ions. Results showed that the initial solution pH was an important factor influencing the chlorate adsorption. The adsorption behavior of chlorate followed the Langmuir adsorption isotherm with a maximum adsorption capacity of 18.2 mg/g. The adsorption kinetics of chlorate on CLDH can be described by the pseudo-second-order kinetic model. It was concluded that the CLDH material is a potential adsorbent for the purification of polluted water with chlorate.


2021 ◽  
Vol 72 (3) ◽  
pp. e423
Author(s):  
Y. Erim Köse

This study aimed to investigate the oxidation profile of wheat germ oil extracted from raw germ during the stabilization with microwave (MW) treatment, and the kinetics of the oxidation parameters (free fatty acids (FFA), peroxide value (PV), thiobarbituric acid (TBA), α-tocopherol, lipase (LA) and lipoxygenase (LOX) enzymes activities) under different storage conditions. For stabilizing raw germ, the MW was treated at 700 W for three minutes. The oxidation parameters for the kinetic modeling were analyzed at different storage times (0, 15, 30, 45, 60,75, 90, and 105. days) and storage temperatures (-18, 0, 4, and 25 °C). The parameters were mathematically modelled and the PV and LA fitted well to the zero-order kinetic model, while FFA with α-tocopherol and TBA followed the first and second-order kinetics, respectively. The kinetic constant (k) was described by an Arrhenius equation and the activation energy ranged from 5.72 to 18.5 kJ/mol for the stabilized germ.


Toxins ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 662
Author(s):  
Enjie Diao ◽  
Kun Ma ◽  
Hui Zhang ◽  
Peng Xie ◽  
Shiquan Qian ◽  
...  

The thermal stability and degradation kinetics of patulin (PAT, 10 μmol/L) in pH 3.5 of phosphoric-citric acid buffer solutions in the absence and presence of cysteine (CYS, 30 μmol/L) were investigated at temperatures ranging from 90 to 150 °C. The zero-, first-, and second-order models and the Weibull model were used to fit the degradation process of patulin. Both the first-order kinetic model and Weibull model better described the degradation of patulin in the presence of cysteine while it was complexed to simulate them in the absence of cysteine with various models at different temperatures based on the correlation coefficients (R2 > 0.90). At the same reaction time, cysteine and temperature significantly affected the degradation efficiency of patulin in highly acidic conditions (p < 0.01). The rate constants (kT) for patulin degradation with cysteine (0.0036–0.3200 μg/L·min) were far more than those of treatments without cysteine (0.0012–0.1614 μg/L·min), and the activation energy (Ea = 43.89 kJ/mol) was far less than that of treatment without cysteine (61.74 kJ/mol). Increasing temperature could obviously improve the degradation efficiency of patulin, regardless of the presence of cysteine. Thus, both cysteine and high temperature decreased the stability of patulin in highly acidic conditions and improved its degradation efficiency, which could be applied to guide the detoxification of patulin by cysteine in the juice processing industry.


2012 ◽  
Vol 77 (7) ◽  
pp. 879-886 ◽  
Author(s):  
Cara Cristina ◽  
Dumitrel Gabriela-Alina ◽  
Glevitzky Mirel ◽  
Perju Delia

The problem of availability of veterinary medicines to treat honeybees is discussed extensively worldwide. An uncontrolled administration of antibiotics may lead to contamination of beehive products and contributes to the problem of food safety. In this study, the kinetics of tetracycline (TC) degradation in honey was studied for samples provided by four sideline beekeepers located in the west region of Romania. The samples of honey were stored in the dark at room temperature for 30 days and subsamples were analyzed every 3 days by Elisa method. The results of the study revealed that the level of tetracycline decreases in time for all honey samples. The tetracycline degradation follows a first-order kinetic model with reaction rate constants between 1.2?10-3 - 2?10-3 days-1. The half-life time of tetracycline in monofloral honeys: acacia and lime was 251 and 232 days respectively. Tetracycline degradation in polyfloral honey was accelerated since ?1/2 of TC was 151 days.


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