Wyniki wyszukiwania - BazTech

1

Determination of phenol levels in some surface water ecosystems of Tirana Area, Albania

Shehi Ardit, Shpati Kleva, Dama Aida, Myrtaj Bledar, Nuro Aurel

Journal of Ecological Engineering

|

2025

|

Vol. 26, nr 2

48--55

EN

The aim of this study was investigating the concentration of phenols in some surface water samples of Tirana area by using UV-VIS technique. Phenols are commonly found in nature because of their natural background and because of human activity including urban wastewater and industrial wastes. Phenol and its derivates are known to have significant ecological toxicity, therefore, determination of its concentrations in water is a valuable parameter for the water quality. UV-VIS method is easy to use, and a low-cost technique but it is also efficient and accurate to determine phenol in trace level. Levels of phenol were measured in four different waterbodies in Tirana area to have an overview about water quality of these important artificial lakes and to find specific reasons and/or phenol sources for them. Water samples were collected in different stations of Tirana artificial lake (10 stations), Paskuqan Lake (8 stations), Farka Lake (8 stations) and Dry Lake reservoir (6 stations). The water sampling was realized monthly from May to October 2024 (except August). Phenol analysis involved method building, method evaluation and quantify of phenol in water samples. Phenols were detected in all the water samples analyzed. The lowest values of phenol were found in the Artificial Lake of Tirana and Dry Lake while the highest values in the Paskuqan Lake and Farka Lake. Almost for all the samples, the concentration of phenols was low in May and high in September. The presence of phenol in these water ecosystems is connected mainly with urban waste. Further-more, experiments indicated that samples had phenol concentration exceeding 3.4 ppm, a level deemed hazardous to aquatic life by the US Environmental Protection Agency (EPA).

2

Preparation of nano SnO2-Sb2O3 composite electrode by cathodic deposition for the elimination of phenol by sonoelectrochemical oxidation

Nsaif Hind Jabbar, Majeed Najwa Saber, Salman Rasha H.

Polish Journal of Chemical Technology

|

2024

|

Vol. 26, nr 3

21--28

EN

The preparation of composite metal oxide to attain high efficiency in removing phenol from wastewater has a great concern. In the present study, the focus would be on adopting antimony-tin oxide coating onto graphite substrates instead of titanium; besides the effect of SbCl3 concentration on the SnO2-Sb2O3 composite would be examined. The performance of this composite electrode as the working electrode in the removal of phenol by sonoelectrochemical oxidation will be studied. The antimony-tin dioxide composite electrode was prepared by cathodic deposition with SnCl2 . 2H2O solution in a mixture of HNO3 and NaNO3, with different concentrations of SbCl3. The SnO2-Sb2O3 deposit layer’s structure and morphology were examined and the 4 g/l SbCl3 gave the more crystallized with nanoscale electrodeposition. The highest removal of phenol was 100% at a temperature of 30° C, with a current density (CD) of 25 mA/cm2 .

3

Microbiological treatment of post-industrial water : Example of efficient bioremediation of the heavily polluted Kalina pond, Poland

Starzec Katarzyna, Stańkowska Emilia, Supel Paulina, Mazur Robert, Surma Piotr, Kaszycki Paweł

Journal of Water and Land Development

|

2024

|

no. 60

236--245

EN

The Kalina pond has been well known as a severely degraded area in the Silesia region, Poland. The environmental deterioration results from high contamination of water and bottom sediments with recalcitrant and toxic organic compounds, mainly phenol. The study was aimed at developing a bioremediation-based approach suitable for this type of polluted areas, involving microbiological treatment of water as a key and integral part of other necessary actions: mechanical interventions and the use of physical methods. During the initial biological treatment stage, autochthonous microorganisms were isolated from contaminated samples of water, soil and sediment, then subjected to strong selective pressure by incubation with the pollutants, and finally, cultivated to form a specialised microbial consortium consisting of five extremophilic bacterial strains. Consortium propagation and its biodegradation activity were optimised under variant conditions enabling bacteria to proliferate and to obtain high biomass density at large volumes allowing for the in situ application. After installing aeration systems in the pond, the consortium was surface-sprinkled to launch bioremediation and then both bacterial frequency and the contaminant level was systematically monitored. The complex remediation strategy proved efficient and was implemented on an industrial scale enabling successful remedial of the affected site. Treatment with the specifically targeted and adapted microbial consortium allowed for removal of most organic pollutants within a four-month season of 2022: the chemical oxygen demand (COD) value decreased by 72%, polyaromatic hydrocarbon (PAH) level by 97%, while the content of total phenols and other monoaromatic hydrocarbons (BTEX) dropped below the detection thresholds.

4

Searching of Phenol-Degrading Bacteria in Raw Wastewater from Underground Coal Gasification Process as Suitable Candidates in Bioaugmentation Approach

Jałowiecki Łukasz, Borgulat Jacek, Strugała-Wilczek Aleksandra, Glaser Mikołaj, Płaza Grażyna

Journal of Ecological Engineering

|

2024

|

Vol. 25, nr 2

62--71

EN

The aim of the conducted study was to isolate, identify and characterize suitable bacterial strains from UCG wastewater as potential candidates for the bioaugmentation approach. For this purpose, the straightforward cultivation procedure and unique biochemical selection were employed to gain insights into the specific properties of bacteria. From the 100 strains isolated from UCG wastewater, three (Paenibacillus pasadensis SAFN-007, Peanibacillus humicus Au34, and Staphylococcus warneri DK131) demonstrated the capacity to degrade phenol and specific biochemical properties. Phenol degradation reached more than 90% for the above-mentioned strains, while the average phenol removal rate for other selected strains was 82.9%, ranging from 66.1% to 90%. The bacterial strains belong to multi-enzyme producers and constitute a possible source of potential technologically important enzymes. Phenotypic microarray plates were used to characterise the metabolic properties of the strains. It was found that 74%, 67.4% and 94.2% of the carbon metabolites tested were utilised by Paenibacillus pasadensis SAFN-007, Peanibacillus humicus Au34 and Staphylococcus warneri DK131, respectively. Among C sources, the strains have the capability to metabolize some substrates appearing in phenol pathways, such as: N-acetyl-D-glucosamine, succinic acid, α-hydroxy-glutaric acid-γ-lactone, bromosuccinic acid, mono-methyl succinate, methyl-pyruvate, p-hydroxy-phenyl acetic acid, m-hydroxyphenylacetic acid, L-galactonic acid-γ-lactone, D-galactonic acid-γ- lactone, phenylethylamine. Bacteria show different levels of tolerance to pH and osmolality, and they can thrive in different habitats. Another characteristic of these strains is their high resistance to many antibiotics (multi-resistant bacteria). These properties allow the use of the isolated bacterial strains as good candidates for bioremediation of phenol-contaminated environments. The wastewater from the underground coal gasification process is an example of a good extreme environment for the isolation of unique bacteria with specific metabolic properties.

5

The Removal of Phenol Through Adsorption onto Synthetic Calcium Phosphates – A Study Encompassing Analyses of Kinetics and Thermodynamics

El Bakri Abdellatif, El Boujaady Hicham, Ferraa Nouhaila, Bennani-Ziatni Mounia

Ecological Engineering & Environmental Technology

|

2024

|

Vol. 25, iss. 4

301--315

EN

The characteristics and suitability of hydroxyapatite (HAP), tricalcium apatite phosphate (PTCa), and octocalcium apatite phosphate (OCPa), which possess similar attributes to those of an ideal adsorbent, were investigated to determine their efficacy in phenol removal. The aim of this paper is to assess the adsorption behavior of phenol on phosphates powders synthesized by the co-precipitation method at ambient temperature. Furthermore, the impact of initial phenol quantities and thermal conditions on the adsorption process was explored. X-ray diffraction analysis revealed the formation of HAP, PTCa, and OCPa structures under room temperature conditions. The sample morphologies were subjected to scrutiny utilizing MEB together with X-ray analysis. Additionally, chemical analysis revealed that Ca/P = 1.6, 1.5, and 1.33 for HAP, PTCa, and OCPa, respectively. The synthesized powders exhibited adsorption abilities of 2.86, 2.74, and 2.52 mg/g for HAP, PTCa, and OCPa, respectively, and reached equilibrium in approximately 80 minutes. The study revealed that the experimental data are appropriately represented by the Langmuir and Freundlich adsorption equations for HAP and PTCa, and Langmuir model in the case of OCPa, as well as by the pseudo-first-order and pseudo-second-order adsorption kinetics. Thermodynamic evaluations, including calculations of ΔG°, ΔH°, and ΔS°, were performed. The results indicated that the adsorption mechanisms exhibited physical characteristics, were thermally absorbing in the case of HAP and exothermic for the other two phosphates, PTCa and OCPa, and occurred spontaneously.

6

Green Synthesis of Nano-Activated Carbon from Reed Stalk – Characterization and Evaluation Performance in Phenolic Water Treatment

Azeez Rana Abbas, Khazal Shahnaz B., Al-Zuhairi Firas K., Hasan Muayad M., Shakor Zaidoon M.

Ecological Engineering & Environmental Technology

|

2024

|

Vol. 25, iss. 10

306--323

EN

During the past few decades, interest in phenolic substances in aquatic environments has increased due to their wide uses in numerous industries despite their high toxicity. This study aimed to investigate removing phenol from contaminated wastewater using synthesized nanoscale-activated carbon (AC) as a sorbent. The AC was synthesized from reed stalks as a local bio-based material using a chemical activation approach. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) in addition to the Fourier transform-infrared spectroscopy (FTIR) were applied to characterize the synthesizedAC. The study tested four different factors using the experimental statistical design, data analysis with Design Expert Software, and a central composite design (CCD) using response surface methodology (RSM) to maximize phenol elimination. These factors involved initial phenol concentration (ranging from 30 to 120 ppm), pH levels (ranging from 2 to 11), concentration of adsorbent range from 50 to 600 ppm, and reaction time range from 30 to 120 minutes. These variables were used as input data for the prediction model to determine the removal efficiency (%) of phenol. The analysis of the ANOVA was conducted to examine the model performance. The analysis results suggested that the most effective model in explaining the process of phenol elimination was the second-order quadratic model, and the predicted data strongly matched the experimental values. The findings revealed that the optimal adsorption conditions obtained from the experimental work were initial phenol concentration of 30 mg·L-1 , adsorbent dose of 600 mg·L -1, pH equal to 2, reaction time of 120 minutes, and the capacity of the adsorption was 30.0825 mg·g -1. As a consequence, the nanoactivated carbon extracted from reed stalks effectively adsorbs phenol from wastewater.

7

Microwave-aided nitration of phenol with inorganic nitrates: inquiry-based learning experiments

Morávková Zuzana, Havlíček Jiří, Doležal Rafael, Bílek Martin, Kolář Karel

Chemistry-Didactics-Ecology-Metrology

|

2024

|

R. 29, NR 1-2

65--83

EN

Current trends in organic synthesis as well as in chemistry education highlight the principles of Green chemistry and call for new synthetic procedures that conform to the actual ecological and economic requirements according to the Green deal and other global challenges. This includes, for instance, replacement of aggressive and toxic reagents, optimisation of synthetic protocols to achieve the highest possible yields within the shortest reaction times, lowering the reaction temperature, solvent recycling and waste minimisation. Considering the present technological advances, replacement of classical heating by microwave irradiation turns out to be an important tool of Green chemistry that permits significant reduction of the reaction time and increase of the yield under certain conditions. In chemistry education alike, several teaching experiments have also been reported in the latest literature to show advantages of the microwave-aided synthesis of various organic compounds or to elucidate basic chemical reactivity principles (e.g. direct carboxamide synthesis, aromatic sulphonation with rearrangement). In the present study, we design a Green chemistry education project focused on microwave-aided nitration of phenol by a set of inorganic metal nitrates (i.e. sodium nitrate, calcium nitrate, copper(II) nitrate, iron(III) nitrate) in concentrated acetic acid. These inquiry-based learning experiments proceed very easily, and the reaction conditions can be controlled to achieve the first, the second or even the third degree of nitration. Along with a necessary minimum of chemistry knowledge and skills, the proposed educational experiments on microwave-aided synthesis encourage students to explore the influence of the inorganic nitrate structure on the phenol nitration products. The basic relationship between the properties of reactants and the course of this interesting organic reaction can be easily monitored by universal pH papers and thin-layer chromatography, and subsequently explained through inductive reasoning. As such, these student-centred experiments are suitable for implementation in inquiry-based chemistry education at universities or high schools oriented in natural sciences.

8

The potential of Stenotrophomonas maltophilia KB2 for phenol degradation under exposure to heavy metal

Gąszczak Agnieszka, Szczyrba Elżbieta, Szczotka Anna

Chemical and Process Engineering : New Frontiers

|

2024

|

Vol. 45, nr 2

art. no. e64

EN

The large diversity of chemical substances present in air, water, or soil makes it necessary tostudy their mutual impact on the effectiveness of microbiological decomposition ofcontaminants. This publication presents the results of the studies aimed at evaluating the effect of two biogenic heavy metals - zinc and copper - on the phenol biodegradation by the Stenotrophomonas maltophilia KB2 strain. The tests were carried out for concentrations ofmetals significantly exceeding the legally permitted wastewater values: for zinc up to13.3 g·m -3, and copper up to 3.33 g·m -3. In the tested metal concentration range, phenol biodegradation by the S. maltophilia KB2 strain was not significantly influenced by theintroduced dose of zinc. While the presence of copper inhibited both biomass growth andsubstrate degradation. Kinetic data of metal and phenol mixtures were analyzed and very goodcorrelations were obtained for the proposed equations. An equation consistents with the Hanand Levenspiel model was proposed for the system S. maltophilia KB2-phenol-copper, whilean equation consistents with the Kai model for the system St. maltophilia KB2-phenol-zinc. The simultaneous presence of Zn and Cu ions in the culture resulted in a stronger inhibition ofphenol biodegradation.

9

Contaminants Removal from Real Refinery Wastewater Associated with Energy Generation in Microbial Fuel Cell

Jabbar Noor Mohsen, Alardhi Saja Mohsen, Al-Jadir Thaer, Dhahad Hayder Abed

Journal of Ecological Engineering

|

2023

|

Vol. 24, nr 1

107--114

EN

Microbial fuel cells (MFCs) pertain to a kind of modern technology for the direct conversion of chemical energy in organic matter from wastewaters into electricity during the oxidation of organic substrates. A system of continuous MFC was constructed for the treatment of real petroleum refinery wastewater (PRW). The treatment of real PRW, operational performance of the MFC system, biodegradation of furfural, and energy output were investigated in this study. The MFC was inoculated by mixed anaerobic bacteria, with Bacillus sp. as the dominant type, and continuously operated for 30 days. The biodegradation of furfural and phenol, which are the most prevalent toxicants in refinery wastewater, was investigated. The MFC system reached maximum energy outputs of 552.25 mW/m3 and 235 mV. In the anodic chamber, the maximum removal of furfural and phenol was higher than 99%, with biodegradation of organic content reaching up to 95%. This study demonstrated the viability of a continuous-flow MFC system as a green technology for the treatment of furfural-rich real refinery effluents while generating electricity.

10

Polymer Inclusion Membrane's 10% Copoly-EEGDMA-Containing Membrane's Lifetime and Optimization for Phenol Transport

Kiswandono Agung Abadi, Rinawati Rinawati, Sukarta I. Nyoman

Ecological Engineering & Environmental Technology

|

2023

|

Vol. 24, iss. 5

254--264

EN

In this research, Polymer Inclusion Membrane (PIM) was created using copoly-eugenol ethylene glycol dimethacrylate (co-EEGDMA) 10% as a carrier, dibenzyl ether (DBE) as a plasticizer, and polyvinyl chloride (PVC) as the base polymer. Following that, the membrane was used in phenol transport experiments under a variety of circumstances, including pH of the phenol in the source phase, NaOH concentrations in the receiving phase, and transport times. The ability and stability of the membrane were also evaluated under several influencing parameters such as plasticizer concentration, salt concentration, and PIM membrane age (lifetime). Phenol concentration was analyzed using UV-Vis spectrophotometer, and PIM membrane was characterized before and after use using Fourier-transform infrared spectroscopy (FT-IR). According to the testing findings, phenol had an ideal pH of 5.5 in the source phase and a concentration of 34.07% in the receiving phase. Additionally, it was discovered that the ideal NaOH content in the receiving phase was 0.5 M with a phenol concentration of 58.24%. The experiments with varied transport times demonstrated that the optimum time was 48 hours with the phenol concentration of 90.82% in the receiving phase. The results of UV-Vis spectrophotometry analysis demonstrated that phenol transportation of 91.54% was achieved with the use of 0.3132 g plasticizer. Under ideal circumstances of pH 5.5 of phenol solution in the source phase, 0.5 M NaOH concentration, and phenol transport time of 48 hours, a membrane prepared from PVC as a base polymer, 10% co-EEGDMA as a carrier, and DBE as a plasticizer can be used to transport phenol. The membrane’s stability was only 24 days when no NaNO3 salt was added, but it grew to 108 days when 0.01 M NaNO3 salt was added.

11

A Review on the Adsorption of Phenol Derivatives from Wastewater

Benaddi Rabia, Osmane Ahmed, Zidan Khadija, El Harfi Khalifa, Ouazzani Naaila

Ecological Engineering & Environmental Technology

|

2023

|

Vol. 24, iss. 4

35--43

EN

Several environmental companies consider phenols compounds to be very dangerous pollutants because they are highly toxic and non-biodegradable, notably their high toxicity in water. For this reason, several processes have been studied by researchers to understand the mechanisms of elimination of phenolic compounds. Adsorption remains the best technique due to its characteristics, in fact, it is non-destructive and simple to use as well as have more other advantages, such as practicality and efficiency and low cost, Therefore, these methods need to be widely developed on an industrial scale to remove phenol derivatives and achieve wastewater quality in accordance with standards. On the other hand, the development of these adsorption methods is highly dependent on new research on materials from abundant natural resources, namely apatites or biomaterials.

12

Effect of a static magnetic field on Saccharomyces cerevisiae growth in wastewater containing phenol and p-chlorophenol

Rutkowska-Narożniak Anna, Pajor Elżbieta

Journal of Water and Land Development

|

2022

|

no. 55

178--184

EN

The effect of a static magnetic field (MF) of 7 mT with phenol (P) or p-chlorophenol (p-chP) concentrations of 100 mg∙dm-3 on the proliferation of Saccharomyces cerevisiae yeast was investigated. The abundance of the microorganism was determined under static culture conditions on a YPG medium with or without the addition of P or p-chP and exposed or unexposed to the MF over 48 h of the experiment. A static MF of 7 mT was shown to have a stimulating effect on S. cerevisiae cell proliferation after 24 h. It was proved that P and p-chP were used as an additional carbon source by yeasts. The greatest stimulation of the growth of the studied microorganisms was observed under the simultaneous effect of an MF and in presence of either P or p-chP. It was generally about 2 times higher at the time of the study than in the control. Statistical analysis of the results was carried out using, among other things, analysis of variance (ANOVA). A statistically significant difference in the growth of the tested microorganisms was observed. The study results indicate the possibility of applying an MF of 7 mT to enhance the process of phenol and p-chlorophenol removal from industrial wastewater.

13

Effect of Zeolite and Activated Carbon Thickness Variation as Adsorbent Media in Reducing Phenol and Manganese Levels in Wastewater of Non-Destructive Testing Unit

Fikri Elanda, Farid Reta Athaya Mutiara, Septiati Yosephina Ardiani, Djuhriah Nanny, Hanurawaty Neneng Yetty, Khair Amar Sharaf Eldin

Journal of Ecological Engineering

|

2022

|

Vol. 23, nr 8

40--48

EN

The production wastewater contains phenol from the Non-Destructive Testing (NDT) unit because it uses solvents; meanwhile, the manganese originates from the metal material washing process. On the basis of laboratory test results, the wastewater originating from the NDT unit of Y Industry, resulted in a phenol level of 2.33 mg/L, exceeding the quality standard of 0.5 mg/L and manganese level of 14.13 mg/L that exceeded the quality standard of 2 mg/L, based on the Regulation of the Minister of the Environment Number 5 of 2014 concerning Wastewater Quality Standards. This research used the pretest-posttest experimental research design without control. The sample in this study was wastewater from the NDT unit of the Y Industry. The average phenol level after passing through the adsorbent media at a thickness of 40 cm, 60 cm, and 80 cm resulted in 0.99 mg/L with 63% reduction, 0.60 mg/L with 77% reduction, and 0,28 mg/L with 89% reduction, respectively. The average manganese level after passing through the adsorbent media at a thickness of 40 cm, 60 cm, and 80 cm resulted in 0.10 mg/L with 61% reduction, 0.06 mg/L with 76% reduction, and 0,05 mg/L with 80% reduction, respectively. The most effective thickness variation in reducing the phenol and manganese levels of NDT wastewater is 80 cm thickness.

14

Application of Emulsion Liquid Membrane Using Green Surfactant for Removing Phenol from Aqueous Solution: Extraction, Stability and Breakage Studies

Mohammed Ahmed A., Al-Khateeb Rasha Waleed

Journal of Ecological Engineering

|

2022

|

Vol. 23, nr 1

305--314

EN

Emulsion Liquid Membrane (ELM) has garnered much attention, for its simple operation and high selectivity for the target solute. For an ELM process to be successful, emulsion stability and formulation of liquid membrane are the two main criteria. This study investigated an ELM formulation to identify a suitable green surfactant over the ordinary ones to reduce the utilization of chemicals. The stability of water-in-oil-in-water (w/o/w) was assessed in the following ways, by altering the concentrations of the egg yolk and NaOH, homogenizer speed, and emulsification time. To ascertain the favorable conditions for phenol extraction, several experiments were performed, adopting the batch process, which included many parameters, like the influence exerted by the pH of the external feed, concentration of surfactant, concentration of the internal phase, time of emulsification, homogenization speed and mixing time. Lower breakage and greater extraction efficiency (0.83% and 82.06%, respectively) were attained at 3.5 pH of the external feed, 4% (v/v) of the surfactant, 0.1 M of NaOH, 7 min of emulsification time, 5800 rpm of homogenizer speed and 3 minutes of mixing time. From the results of this study, egg yolk emerged as a good green surfactant. Thus, the ELM process holds promise as an effective technology for stripping phenol from aqueous solutions.

15

Simultaneous removal of phenol and Cu(II) from wastewater by tallow dihydroxyethyl betaine modified bentonite

Hu Xiangyang, Wang Bao, Yan Gengsheng, Ge Bizhou

Archives of Environmental Protection

|

2022

|

Vol. 48, no. 3

37--47

EN

An organobentonite modified with an amphoteric surfactant, tallow dihydroxyethyl betaine (TDHEB), was used as an adsorbent to simultaneously remove Cu(II) and phenol from wastewater. The characteristic of the organobentonite (named TDHEB-bentonite) was analyzed by X-ray diffraction, Fourier-transform infrared spectra and nitrogen adsorption-desorption isotherm. Batch tests were conducted to evaluate the adsorption capacities of TDHEB-bentonite for the two contaminants. Experiment results demonstrated that the adsorption of both contaminants is highly pH-dependent under acidic conditions. TDHEB-bentonite had about 2.0 and 5.0 times higher adsorption capacity toward Cu(II) and phenol, respectively, relative to the corresponding raw Na-bentonite. Adsorption isotherm data showed that the adsorption processes of both contaminants were well described by Freundlich model. Kinetic experiment demonstrated that both contaminants adsorption processes correlated well with pseudo-second-order model. Cu(II) had a negative impact on phenol adsorption, but not vice versa. Cu(II) was removed mainly through chelating with the organic groups (-CH2CH2OH and -COO-) of TDHEB. Otherwise, partition into the organic phase derived from the adsorbed surfactant was the primarily mechanism for phenol removal. Overall, TDHEB-bentonite was a promising adsorbent for removing Cu(II) and phenol simultaneously from wastewater.

16

Jaki wpływ mają nanocząstki tlenku niklu na wzrost szczepu Stenotrophomonas maltophilia KB2 w obecności fenolu?

Gąszczak Agnieszka, Szczyrba Elżbieta, Szczotka Anna, Kolarczyk Hanna, Sołtys Elżbieta, Janus Bożena

Prace Naukowe Instytutu Inżynierii Chemicznej Polskiej Akademii Nauk

|

2021

|

nr 25

57--74

PL

Wprowadzenie do hodowli szczepu St. maltophilia KB2 nanocząstek tlenku niklu nie zahamowało procesu biodegradacji fenolu, a reakcja populacji bakterii była uzależniona od stężenia nanocząstek i użytego surfaktantu. Opracowano metodykę przygotowania stabilnej dyspersji badanych nanocząstek oraz oceniono wpływ wybranych surfaktantów na wzrost komórek szczepu St. maltophilia KB2.

EN

The introduction of nickel oxide nanoparticles into the St. maltophilia KB2 cultures did not inhibit the phenol biodegradation process, and the reactions of the bacterial population were depended on the nanoparticles concentrations and the surfactant used. The methodology for the preparation of the tested nanoparticles stable dispersion was developed and the influence of selected surfactants on the growth of St. maltophilia KB2 cells was assessed.

17

Physicochemical Characterization of Pomegranate (Punica Granatum L.) Native to Jordan During Different Maturity Stages: Color Evaluation Using the Cielab and Cielch Systems

Pérez Soraya Mercedes

Journal of Ecological Engineering

|

2021

|

Vol. 22, nr 6

214--221

EN

Punica granatum L. study is interesting for the functional properties associated to its Phenolic compounds and high volumes of production of this fruit in Jordan. The pomegranate type "pale arils" from Abu Ziyad valley were evaluated during different stages between 20 to 140 days after full bloom, with techniques of chelation, colorimetry and spectrophotometry. The results show that the increasing of sphericity (0.79 to 0.91), size diameter (65.58 to 90.41 mm), juice yield (46.03 to 55.67%), arils mass (31.70 to 61.23%), TSS total soluble solids (11.01 to 16.80), pH (2.7 to 3.6) and anthocyanins (7.43 to 12.41 Cyannidine 3 glucoside/100 g) were associated with the decreasing of thickness of the rind (4.9 to 2.77 mm), TTA Titrable total acidity (3.5 to 1.1%), TPC Total phenolics (389.61 to 251.52 mg Gallic acid/100 g), flavonoids (0.73 to 0.40 mg Catechine/g), tannins (8940.11 to 3324.79 ppm), AA Antioxidant Activity (63.41 to 48.84%) and Ascorbic acid content (28.91 to 9.48 mg/100 g); presenting significant differences p≥0,5. The paleness of rind and arils is positively related to the anthocyanin content expressed by "a" and "C" color coordinates. The actual investigation demonstrates that high values TSS-pH, low content of tannins and TTA could be successfully indicators of maturity stages rather than the concentration of anthocyanins.

18

Growth Kinetics and Toxicity of Pseudomonas fredriksbergsis Grown on Phenol as Sole Carbon Source

Aljbour Salah H., Khleifat Khaled M., Al Tarawneh Amjad, Asasfeh Batool, Qaralleh Haitham, El-Hasan Tayel, Magharbeh Mousa K., Al-Limoun Muhamad O.

Journal of Ecological Engineering

|

2021

|

Vol. 22, nr 10

251--263

EN

Phenol is one of the main pollutants that have a serious impact on the environment and can even be very critical to human health. The biodegradation of phenol can be considered an increasingly important pollution control process. In this study, the degradation of phenol by Pseudomonas fredriksbergsis was investigated for the first time under different growth conditions. Six different initial concentrations of phenol were used as the primary substrate. Culture conditions had an important effect on these cells' ability to biodegrade phenol. The best growth of this organism and its highest biodegradation level of phenol were noticed at pH 7, temperature 28 °C, and periods of 36 and 96 h, respectively. The highest biodegradation rate was perceived at 700 mg/L initial phenol concentration. Approximately 90% of the phenol (700 mg/L) was removed in less than 96 hours of incubation time. It was found that the Haldane model best fitted the relationship between the specific growth rate and the initial phenol concentration, whereas the phenol biodegradation profiles time could be adequately described by the modified Gompertz model. The parameters of the Haldane equation are: 0.062 h−1, 11 ppm, and 121 ppm for Haldane’s maximum specific growth rate, the half-saturation coefficient, and the Haldane’s growth kinetics inhibition coefficient, respectively. The Haldane equation fitted the experimental data by minimizing the sum of squared error (SSR) to 1.36×10-3.

19

Anaerobic Digestion of Wheat Straw Pretreated with Soaking in Water and Alkali Medium

Zdeb Magdalena

Journal of Ecological Engineering

|

2021

|

Vol. 22, nr 9

246--254

EN

The influence of the alkaline pretreatment of wheat straw with use 0.05M solution of NaOH by 22 hours at 25 °C temperature on the effectiveness of anaerobic digestion under mesophilic condition was the subject of this study. The water soaked straw was used as a control. The results showed that alkaline pretreatment improved the solubility of the straw biomass, increasing dissolved COD and concentration of VFA in the feedstock of 10% and 21%, respectively, compared to the water soaked samples. Consequently, the cumulative biogas yield was enhanced by 21.5%, reaching 412.1 mL gVS-1 for the pretreated biomass. The digestates were similar in terms of TS and VS, but it significantly differed in terms of phenols concentration, the content of which was considerably higher both in the feedstock as also as in digestate containing alkaline pretreated straw. Initial concentration of phenols in the feedstock of 27 mg L-1 did not block the anaerobic digestion, although its inhibiting effect is forecasted. It was concluded that soaking the straw at low loading of NaOH (4% of raw mass (w/w)) under ambient conditions can efficiently improve its usability for biogas production.

20

Covalent immobilization of laccase on Fe3O4-graphene oxide nanocomposite for biodegradation of phenolic compounds

Rouhani Shamila, Azizi Shohreh, Maaza Malik, Mamba Bhekie, Msagati Titus A. M.

Environment Protection Engineering

|

2021

|

Vol. 47, nr 1

85--99

EN

Laccase from Trametes Versicolor (E.C. 1.10.3.2) was immobilized on the Fe3O4–graphene hybrid nanocomposite through the covalent attachment method (Lac/Fe3O4/GO). The effect of immobilization conditions on the activity and recovered activities such as contact time, the concentration of glutaraldehyde and enzyme was evaluated. The recovered activity of the immobilized laccase on the Fe3O4–graphene oxide nanocomposite was ca. 86%. Immobilized laccase unlike free laccase retained the activity and exhibited higher resistance to temperature and pH changes and also improved storage and thermal stability. Approximately 70% of relative activity for immobilized laccase was remained after being incubated for 2 h at 55 °C, but free laccase only remained 48%. Immobilized laccase retained 88% of initial activity after storage for 20 days, however, the free laccase only 32%. Finally, Lac/Fe3O4/GO capability was evaluated by the oxidation of phenol, p-chlorophenol, and 2,4-dichlorophenol. Lac/Fe3O4/GO was characterized by SEM, EDX, FT-IR, and AGFM.