Improvement Of Biodegradability Research Articles

Insight into the evolution of antibiotic resistance genes and microbial community during spiramycin fermentation residue composting process after thermally activated peroxydisulfate pretreatment

Previous research has been demonstrated that the residual unextracted antibiotics in spiramycin fermentation residue (SFR) could be efficiently removed by thermally activated peroxodisulfate (TAP) pretreatment, indicating the improvement of biodegradability. This study aimed to investigate the effect of TAP pretreatment on the succession of bacterial community and fate of antibiotic resistance genes (ARGs) during SFR composting. Results indicated that TAP pretreatment increased the composting temperature and promoted the decomposition of organic matters. Furthermore, TAP pretreatment could increase bacterial alpha diversity and significantly reduce the relative abundance of ARGs (1.13–1.75 times) and mobile genetic elements (MGEs) (1.13–1.32 times) after composting. The compost of pretreated SFR by TAP could reduce the enrichment of ARGs and MGEs in the bacterial community, especially the rRNA methylase genes of ermB (4–142-folds). Redundancy analysis showed that Actinobacteria, Bacteroidetes, Proteobacteria and horizontal gene transfer mediated by MGEs (intI1) was positively related to the changes in ARGs (accounted for 97.4%). Network analysis showed that Firmicutes was the main bacterial hosts of ARGs and MGEs. These findings demonstrated that TAP pretreatment combined composting was a promising strategy for SFR safe treatment and disposal that could reduce the proliferation and transfer of ARGs.

Effect of rhamnolipids on the fungal elimination of toluene vapor in a biotrickling filter under stressed operational conditions

The application of rhamnolipids in a fungal-cultured biotrickling filter (BTF) has a significant impact on toluene removal. Two BTFs were used; BTF-A, a control bed, and BTF-B fed with rhamnolipids. The effect of empty bed residence times (EBRTs) on toluene bioavailability was investigated. Removal of toluene was carried out at EBRTs of 30 and 60 s and inlet loading rates (LRs) of 23–184 g m−3 h−1. At 30 s EBRT, when inlet LR was increased from 23 to 184 g m−3 h−1, the removal efficiency (RE) decreased from 93% to 50% for the control bed, and from 94% to 87% for BTF-B. Increasing the EBRT simultaneously with inlet LRs, confirms that BTF-A was diffusion-limited by registering a RE of 62% for toluene inlet LR of 184 g m−3 h−1, whereas BTF-B, achieved RE > 96%, confirming a significant improvement in toluene biodegradability. Overall, the best performance was observed at 60 s EBRT and inlet LR of 184 g m−3 h−1, providing a maximum elimination capacity (EC) of 176.8 g m−3 h−1 under steady-state conditions. While a maximum EC of 114 g m−3 h−1 was observed under the same conditions in the absence of rhamnolipids (BTF-A). Measurements of critical micelle concentration showed that 150 mg L−1 of rhamnolipids demonstrated the lowest aqueous surface tension and maximum formation of micelles, while 175 mg L−1 was the optimum dose for fungal growth. Production rate of carbon dioxide, and dissolved oxygen contents highlighted the positive influence of rhamnolipids on adhesive forces, improved toluene mineralization, and promotion of microbial motility over mobility.

Removal of recalcitrant organics in reverse osmosis concentrate from coal chemical industry by UV/H2O2 and UV/PDS: Efficiency and kinetic modeling

The lack of stability in catalytic ozonation treatment of reverse osmosis (RO) concentrate from coal chemical industry calls for new advanced oxidation processes. Herein, UV/H2O2 and UV/PDS were employed to remove the bulk recalcitrant organics in the RO concentrate with a focus on the process efficiency and kinetic modeling. Results show that UV/H2O2 overmatched UV/PDS in reducing the COD and DOC of the wastewater and the advantage became more evident in aspects of biodegradability improvement and energy cost. Specifically, the COD and DOC were removed by 62.0% and 55.5% with UV/H2O2 (6 mM) while the BOD5/COD was elevated to 0.54 at a specific energy consumption of 0.83 kWh g−1 (lab-scale). The UV/H2O2 process also exhibited a good adaptability to the fluctuation of wastewater quality. Afterwards, the reaction rate constants of the bulk organics upon UV photolysis and HO• oxidation were calculated based on pseudo-first-order kinetics and radical steady-state approximation of DOC removal in the bench-scale UV/H2O2 reactor. A computational fluid dynamics model was then developed for the analysis of distributions of flow, radiation and chemicals in flow-through reactors which facilitated the practical process efficiency assessment. This work demonstrates the applicability of UV/H2O2 in removing recalcitrant organics in the RO concentrate and presents an approach from bench-scale experiments to flow-through system evaluation.

Optimization of 2-Chlorophenol Removal Using Ultrasound/Persulfate: Prediction by RSM Method, Biodegradability Improvement of Petrochemical Refinery Wastewater

Optimization of 2-Chlorophenol Removal Using Ultrasound/Persulfate: Prediction by RSM Method, Biodegradability Improvement of Petrochemical Refinery Wastewater

Treatment of polyvinyl alcohol containing wastewater in two stage spiral symmetrical stream anaerobic bioreactors coupled a sequencing batch reactor

This work aimed to study the treatment of polyvinyl alcohol containing wastewater (PVA-containing wastewater) discharged from textile industry. The batch experiment verified the feasibility of anaerobic treatment and determined that the optimal substrate COD was around 3000 mg/L. The single spiral symmetrical stream anaerobic bioreactor (SSSAB) was used for treating PVA-containing wastewater, which shows the stability of SSSAB and the improvement of biodegradability of wastewater. Finally, two stage SSSABs coupled SBR was proposed. By this scheme, under the influent COD of 3014 mg/L and PVA of 413 mg/L, the COD and PVA removal reached 89.4% and 90.7%, respectively, which were higher than the values obtained by other schemes. Contribution rates of reactors show that each reactor plays an essential role, and SEM images show the unique of microbial flora in each SSSAB. The SSSAB-SSSAB-SBR process can provide an alternative to the chemical methods for treating PVA-containing wastewater.

Fabrication of sandwich-like super-hydrophobic cathode for the electro-Fenton degradation of cefepime: H2O2 electro-generation, degradation performance, pathway and biodegradability improvement

Several composite cathodes were prepared using graphite, carbon nanotube (CNT) and PTFE, and their elemental composition, surface morphology, physical and electrochemical properties were studied by various characterization techniques. It was found that the hydrophobic property of the prepared cathodes could be greatly enhanced by changing their surface morphologies using polyurethane sponge in cathode-shaping, which successfully allowed the preparation of super-hydrophobic carbon cathode, resulting in the enhanced reduction of O2 to H2O2. Based on the above finding, a sandwich-like super-hydrophobic carbon cathode was fabricated and used in the electro-Fenton process for the degradation of cefepime. The recommended cathode exhibited an ideal performance for H2O2 electro-generation and a favorable stability. The cathode submerged in air-aeration solution (pH 3.0) has produced 376 mg L−1 H2O2 with an observed current efficiency (CE) of 40 % via the electrolysis of 60 min at the optimum potential. The developed electro-Fenton process presented the degradation efficiency of nearly 100 % within 10 min for 60 mg L−1 cefepime, in which the degradation of cefepime mainly depended on the generation of hydroxyl radicals (∙OH). The organic intermediates formed during cefepime degradation were identified and the degradation pathway was proposed. More over, the electro-Fenton degradation of cefepime evidently reduced the solution toxicity and improved the biodegradability, suggesting the electro-Fenton oxidation may be adopted as a pretreatment alternative prior to the biological treatment of cefepime-containing wastewater.

Using banana peel waste to synthesize BPAC/ZnO nanocomposite for photocatalytic degradation of Acid Blue 25: Influential parameters, mineralization, biodegradability studies

In this study, Acid Blue 25 (AB25) removal was investigated by photocatalytic degradation using banana peel activated carbon (BPAC) and zinc oxide (ZnO) nanocomposite. The nanocomposite was synthesized by the physical mixing method. The BPAC/ZnO nanocomposite was characterized by XRD, FT-IR, FESEM, EDX-mapping, and BET. The effective parameters, including nanocomposite mixing ratio (BPAC:ZnO), pH, initial dye concentration, nanocomposite concentration, aeration rate, and UV light intensity was studied on the degradation of AB25 by the OFAT method. The results indicated that the removal efficiency of AB25 was obtained 94% after 150 min at the optimum conditions of nanocomposite mixing ratio 3:7 (BPAC:ZnO), pH = 5, initial dye concentration = 150 mg L-1, nanocomposite concentration = 0.6 g L-1, aeration rate = 5 L min-1, and UV light intensity = 16 W. Also, the energy consumption at the optimum condition of parameters was obtained 631 kWh kg-1. Moreover, COD and TOC removal was obtained 78% and 61%, respectively. The average oxidation state (AOS) and carbon oxidation state (COS) of AB25 solution were increased after photocatalytic degradation, indicating biodegradability improvement. Also, under the optimum condition of parameters, the effect of scavengers on photocatalytic degradation of AB25 was examined. The results revealed that photo-generated holes and superoxide radicals played a significant role in the degradation process. The reusability of the nanocomposite was studied in several successive experiments, and the degradation efficiency declined from 94% to 82% after four cycles.

Carbon felt modified with N-doped rGO for an efficient electro-peroxone process in diuron degradation and biodegradability improvement of wastewater from a pesticide manufacture: Optimization of process parameters, electrical energy consumption and degradation pathway

In this study, diuron abatement in aqueous medium and the remediation of wastewater from a pesticide manufacture were studied by the E-peroxone process, using carbon felt modified with N-doped rGO (N-rGO/CF) as cathode and Ti/PbO2 anode. Compared with the unmodified CF, the N-rGO/CF displayed a higher response current, improved oxygen reduction activity, and larger BET specific surface area. Also, the modified CF provided a higher H2O2 production rate. The influence of several effective parameters on the diuron degradation rate in aqueous medium by the E-peroxone process was systematically explored by central composite design-response surface methodology; the approach suggested the optimal operating condition at pH of 9, applied current of 500 mA, Na2SO4 of 0.05 M, ozone flow of 1 L min−1, and operating time of 15 min to attain the maximum removal of diuron. At the optimal condition, N-rGO/CF cathode increased diuron degradation rate and decreased electrical energy consumption rather than CF cathode, in the E-peroxone system. Radical quenching experiment and degradation pathway of diuron revealed that hydroxyl radicals were the dominant reactive oxidants. A possible degradation mechanism was proposed based on hydroxylated and demethylated products identified during diuron degradation. No significant difference of the electro-generated H2O2 after 10 successive recycles confirms the admirable reusability of N-rGO/CF. The application of the process for pesticide wastewater increased BOD5/COD ratio significantly from 0.041 (for non-treated wastewater) to 0.4 during 90 min treatment, showing a substantial improvement of the biodegradability of the wastewater. Accordingly, the E-peroxone system can be utilized as a promising pretreatment step before a biological process to facilitate and shorten the length of the biological treatment. The findings of this study could offer valuable information for practical applications of the E-peroxone system in the treatment of pesticide-manufacturing wastewater.

Optimized Study and Column Experiments on Treatment Process of Metronidazole Pharmaceutical Wastewater by Microelectrolysis and Fenton Oxidation

One of the most important wastewater treatment processes is microelectrolysis, which is extensively used in the primary treatment of pharmaceutical wastewater. In this study, microelectrolysis, as a pretreatment method for the refractory metronidazole pharmaceutical wastewater (MPW) of choice, was improved using the Fenton process and used to remove the chemical oxygen demand (COD) and improve the biochemical capability of MPW. The results showed that the highest COD removal of 40.8% was obtained in the presence of optimized significant factors and the BI (BI = biochemical oxygen demand over five days/COD) of MPW increased from 0.10 to 0.31. In addition, the ultraviolet–visible (UV–Vis) spectroscopy demonstrated that metronidazole in MPW was effectively removed during the combined processes. All these results showed that microelectrolysis combined with Fenton oxidation for MPW was an effective treatment process to achieve higher COD removal and biodegradability improvement. Finally, the breakthrough curves at different flow rates were measured to prove the feasibility of the combined process under optimal conditions.

Treatment of Biorefractory Organic Compounds in Dyeing and Printing Process Textile Wastewater with Electron Beam Radiation

Abstract The biodegradability improvement of simulated textile dyeing (reactive), printing, and overall wastewater was carried out by electron beam (e-beam) radiation for an activated sludge proces...

Atrazine biodegradation in soil by Aspergillus niger

AbstractAtrazine is a commonly used herbicide in the Mexican agricultural industry even though it is hazardous for human and animal health. Before reaching its mineralization, this herbicide infiltrates through soil, producing toxic compounds and contaminating groundwater sources. Considering that Aspergillus niger (A. niger) is a filamentous fungus that degrades pectin, cellulose, and other organic polymers, this study analyzes its use to accelerate atrazine mineralization under optimal parameters of temperature, soil humidity, and a co‐substrate for bio‐stimulation. Different atrazine concentrations were used, from 0 ppm to 1000 ppm, in order to measure the growth of its filaments. Glucose and Opuntia ficus indica residues were analyzed as co‐substrates for A. niger biodegradation improvement. A DOE analysis was used to establish optimal treatment conditions. The findings in this study show that a 10 wt% of O. ficus indica as a co‐substrate with 80% humidity achieved atrazine biodegradation in the order of 70% to 75% in 6 days.

Improvement in biodegradability of paper mill wastewater by anatase TiO2 predominant in {001} facet in the batch and packed bed photoreactor (PBPR)

Improvement in biodegradability of paper mill wastewater by anatase TiO2 predominant in {001} facet in the batch and packed bed photoreactor (PBPR)

Moving-bed biofilm reactor combined with three-dimensional electrochemical pretreatment (MBBR-3DE) for 2,4-D herbicide treatment: application for real wastewater, improvement of biodegradability.

2,4-Dichlorophenoxyacetic acid (2,4-D) is a herbicide that is considered as a carcinogenic and highly toxic contaminant, and due to its biological and chemical stability, its degradation is very difficult. Therefore, this study aimed to investigate a hybrid system's efficiency of three-dimensional electrochemical (3DE) process and a moving bed biofilm reactor (MBBR) in removing 2,4-D herbicides from aqueous solutions. In this experimental study, the electrochemical degradation of 2,4-D herbicide in a 3DE process with a G/β-PbO2 anode was first investigated as a pretreatment process. Then, in the post-treatment stage, MBBR with continuous flow was used. The amount of aeration in the MBBR reactor was 4 L min−1, and the amount of dissolved oxygen (DO) was in the range of 3–5 mg L−1. The effect of various parameters such as hydraulic retention time (HRT) and filling ratio were investigated. The amount of sewage injection was set between 0.001–0.004 L min−1. Routine microbiological biochemical tests were used to detect bacteria. BOD5/COD, COD/TOC, AOS, and COS ratio parameters were used to determine the biodegradability of 2.4-D due to the effluent of the 3DE process. The results showed that with increasing current density, decreasing pH, decreasing herbicide concentration and increasing electrolysis time, the herbicide degradation efficiency increased by 3DE pretreatment process. Based on the results of MBBR post-treatment process efficiency, with increasing HRT and filling ratio, the herbicide removal efficiency increased. According to the results, the highest removal efficiencies of 2,4-D and COD herbicides were obtained during HRT of 24 h, and the filling ratio of 70% were 97.33% and 88.95%, respectively. The consortium of 2,4-D degrading bacteria identified in this study included E. coli, Enterobacter spp., Bacillus spp., Alcaligenes spp., Proteus spp., Acinetobacter spp., Pseudomonas spp., Arthrobacter, and Brevundimonas vesicularis. In the MBBR biological process, the reaction kinetics followed the Grau second-order model (R2 = 0.98). In general, the results showed that the combined process of 3DE with G/β-PbO2 anode and MBBR biological process has relatively high efficiency in 2,4-D herbicide degradation and can be used as a suitable complementary treatment method in wastewater containing non-degradable compounds such as phenoxy herbicides, e.g., 2,4-D should be used.

Comprehensive in silico and gene expression profiles of MnP family genes in Phanerochaete chrysosporium towards lignin biodegradation

Phanerochaete chrysosporium (Pc) is the primary fungal source for Lignin degrading enzymes (LDEs). A comprehensive in silico and gene expression analysis was carried out for one of the most important LDEs called manganese peroxidases (PcMnPs). We have identified five PcMnPs in BLAST genomic survey, which are putatively glycosylated extracellular proteins (39–40 kDa). These contain putative regulatory motifs for various factors, like, stress, metal ions, and nutrient components, peroxidase and ligninase motifs, and secretory signal peptides. PcMnPs also exhibit potent variation in transcript accumulation in time and stress-specific manner. Interestingly, PcMnPs were significantly expressed at later growth stages (144 h) and also found to be induced by different stresses and cofactors, such as, MnSO4, H2O2 and heat stress. Particularly, PcMnP1, PcMnP3, and PcMnP4 showed elevated expression in different time intervals and also under different concentration of nutritional components and stress treatments. In addition, molecular modeling and gene expression results indicate that PcMnP1 might serve as a potential candidate for lignin biodegradation. The present study revealed the structural variations and functioning of different modes of regulation of expression of the PcMnPs, which would be useful for the improvement of biodegradation of lignocelluloses and other recalcitrant wastes.

Experiment study on the separation of bituminous coal adsorption and the synergism of ultraviolet and electrochemistry in the pretreatment of coal chemical wastewater

Although clean coal utilization has attracted much attention, it is challenging to treat coal chemical wastewater. In this work, the coking wastewater was treated by bituminous coal adsorption and composite advanced oxidation technology. The effect of adsorption on organic separation and the synergy between UV and electrochemistry were investigated. The results indicated that the removal of total organic carbon (TOC), chroma, and UV254 by bituminous coal adsorption was effective. And polycyclic aromatic hydrocarbons were preferentially adsorbed, followed by phenols and aliphatic hydrocarbons. After bituminous coal adsorption and electrochemical/UV/H2O2 treatment, the TOC of coking wastewater decreased by 68.92%, which was better than adsorption/electrochemical and adsorption/UV. Through excitation-emission matrix (EEM) and gas chromatography-mass spectrometry (GC–MS) analysis, the improvement of biodegradability was attributed to the reduction of polycyclic aromatic hydrocarbons, long-chain alkane, and nitrogen heterocyclic compounds in the coking wastewater. UV photocatalysis and electrochemical had synergistic effects on the degradation of polycyclic aromatic hydrocarbons. Besides, the active chlorine could be regulated by adjusting the current density and the dosage of hydrogen peroxide.

The effect of PEO parameters on the properties of biodegradable Mg alloys: a review

This paper comprehensively reviews recent research carried out in the field of preparation of bioactive coatings on magnesium (Mg)–aluminum (Al)–zinc (Zn) alloys by using the plasma electrolytic oxidation (PEO) method and investigation of factors affecting it. Magnesium–aluminum–zinc alloys (AZ grades) have been developed for use as biodegradation materials because the addition of aluminum and zinc as alloying elements can ameliorate their mechanical properties and increase corrosion resistance over those of pure magnesium alone without decrement in biocompatibility. Among the common methods for improvement of biodegradation, corrosion resistance and biocompatibility of magnesium alloys, surface modification techniques have been more effective. PEO is a relatively novel surface modification technique that provides excellent wear- and corrosion-resistant coatings on lightweight metals, in particular on magnesium and its alloys. The processing parameters of PEO, such as pulse frequencies, applied voltages, oxidation time, electrolyte concentrations and substrate chemical composition, are some of the major factors that determine the quality of the coatings in terms of corrosion resistance and bioactivity in body fluid solutions. Considering the fact that comprehensive review articles on the effect of PEO parameters on the properties of magnesium alloys have not been published in recent years, the aim of the present text is to provide an understanding of all aspects of these process parameters.

Integrated Alkali-Electrochemical Process for Wastewater Treatment

Solid waste mismanagement causes environmental contamination. Sewage sludge is the byproduct of the wastewater treatment process and contains pathogenic organisms (e.g Salmonella spp., Escherichia coli, etc.). Anaerobic digestion is widely used for sewage sludge treatment. However, the major drawback of this process is the sluggish rate of sludge biodegradation. Therefore, the retention time in the typical digester is long (between 20-30 days) which consequently results in substantial energy consumption. On the other hand, approximately 50- 60 % of the operational cost in the wastewater treatment plant is dedicated to the treatment and disposal of waste. Hence, it is essential to develop a treatment method to decrease energy consumption.Alkaline treatment is an attractive process for sludge destruction and improvement in the sludge biodegradability. Furthermore, electrochemical oxidation of the organic materials is an environmentally friendly alternative pathway to disintegrate the sludge microbial cells and eliminate the pathogen bacteria from biosolid for safe disposal. Therefore, the combined alkaline electrochemical technique could expedite waste degradation by using the synergetic functions and increase efficiency of the treatment.To overcome the challenges related to the conventional treatment method, our research group has developed a novel, energy-efficient mixed alkali-electrochemical sludge treatment in a membraneless electrochemical system at room temperature and low applied potential. In this study, the bimetallic (platinum-iridium) nanocatalyst was synthesized with modified polyol method. The thermal behavior of the raw sludge and the residue biosolid after electrolysis was evaluated by using thermogravimetric analysis (TGA). To determine the effect of electrolysis on the chemical structure of biosolid, the Fourier-transform infrared spectroscopy-Attenuated Total Reflection (FTIR-ATR) and elemental analysis techniques were applied. Ammonia was produced as a byproduct of the waste treatment which can be converted to hydrogen through electrolysis. A considerable amount of solid reduction was achieved by implementing a short electrolysis treatment which diminished the waste transportation and disposal cost to a large extend. Furthermore, the energy consumption was significantly lower than the previous research studies. In this presentation, results from this study including (i) the electrochemical performance of catalyst for sewage sludge treatment (ii) pathogen disinfection and (iii) biosolid characterization will be provided.

Anaerobic digestion of sewage sludge pretreated by high pressure homogenization using expanded granular sludge blanket reactor: Feasibility, operation optimization and microbial community

Biogas production via anaerobic digestion from sewage sludge have been investigated in different reactors. However, the efficient conversion of sewage sludge into biogas via continuous operational reactor with short retention time, have been overlooked. Considering the liquid-like property of sewage sludge pretreated by high pressure homogenization (HPH), in this study, the biogas production from HPH-pretreated sewage sludge was investigated in an expanded granular sludge blanket (EGSB) reactor for 219 d. Under optimized hydraulic retention time (HRT) of 6 d, upflow velocity of 4 m/h and organic loading rate (OLR) of 1.66 kg total chemical oxygen demand (TCOD)/(m3·d), the raw sludge was digested with a biogas production, methane content in biogas, TCOD and volatile solid (VS) removal of 215 mL/(gTCOD)·d, 52 %, 43 % and 35 %, respectively. After sludge HPH pretreatment, the HRT was shortened to 5 d due to the sludge disintegration of 24 % and enhanced growth of acetolastic Methanosaeta and hydrogenotrophic Methanolinea, subsequently, the biogas production, methane content in biogas, TCOD and VS removal increased to 240 mL/(gTCOD)·d, 57 %, and 58 % and 43 %, respectively. Abundance of dominant bacterial phylum Chloroflexi and archaeal genera Methanosaeta significantly increased for the improvement of organic biodegradation and methane production, respectively, reflecting the successful EGSB operation. Due to the good performances of EGSB reactor for the anaerobic digestion of HPH-pretreated sewage sludge, the combined HPH-pretreatment and EGSB reactor is promising to be applied in sustainable wastewater treatment plants.

Mechanical, optical and antioxidant properties of 7-Hydroxy-4-methyl coumarin doped polyvinyl alcohol/oxidized maize starch blend films

In the present study, the different weight ratios of 7-hydroxy-4-methyl coumarin (7H4MC) mixed polyvinyl alcohol (PVA)/oxidized maize starch (OMS) blend films were achieved by the solvent casting method and coded as PSC. The prepared film samples were characterized by employing techniques such as FTIR, UTM, and SEM. The film samples were also subjected to their wettability, biodegradation and migration rate studies. Experimental outcomes showed that strong intermolecular hydrogen bonding between components of the blend films contribute to increase the mechanical properties, smoother surface morphology, increase in surface hydrophobicity, improvement in biodegradability, and exhibited migration rates below the overall migration limit (OML). Furthermore, moisture content, density, optical properties, water absorption, water solubility, water vapour transmission rate and antioxidant properties are discussed in detail. With all these properties, PVA/OMS/7H4MC blend films have the potential to use as packaging material.

Treatment of petroleum wastewater using synthesised haematite (α-Fe2O3) photocatalyst and optimisation with response surface methodology

ABSTRACT Haematite (α-Fe2O3) photocatalyst (HPC) has been synthesised by a modified solution combustion method. The prepared catalyst was characterised with a Scanning Electron Microscopy (SEM) and X-ray Diffractometer (XRD). Catalyst characterisation confirmed its composition and phase, but it also showed a slight lack in uniformity and crystallinity due to uncontrolled combustion caused by the modifications made to the preparation procedure. The photocatalyst was tested for the removal of pollutants present in the petroleum refinery wastewater (PRW) under UV-A lamp solar irradiation. A central composite design (CCD) with response surface methodology (RSM) was employed for optimisation of the model. The PRW treatment achieved a marked improvement in biodegradability, raising the biological oxygen demand (BOD)/chemical oxygen demand (COD) ratio from 0.074 to 0.604 in 90 min and percentage COD removal was 90.85% at a catalyst concentration of 5 g/L, pH 7.5 and hydrogen peroxide (H2O2)/COD ratio of 1 mg/mg. RSM optimisation predicted a maximum theoretical BOD/COD ratio of 0.661 and percentage COD removal of 94.73% at a catalyst concentration of 1.494 g/L, pH 7.5 and hydrogen peroxide (H2O2)/COD ratio of 1 mg/mg.