Catalytic oxidation of toluene by manganese oxides: Effect of K+ doping on oxygen vacancy.

Alkali metal potassium was beneficial to the electronic regulation and structural stability of transition metal oxides. Herein, K ions were introduced into manganese oxides by different methods to improve the degradation efficiency of toluene. The results of activity experiments indicated that KMnO4-HT (HT: Hydrothermal method) exhibited outstanding low-temperature catalytic activity, and 90% conversion of toluene can be achieved at 243°C, which was 41°C and 43°C lower than that of KNO3-HT and Mn-HT, respectively. The largest specific surface area was observed on KMnO4-HT, facilitating the adsorption of toluene. The formation of cryptomelane structure over KMnO4-HT could contribute to higher content of Mn3+ and lattice oxygen (Olatt), excellent low-temperature reducibility, and high oxygen mobility, which could increase the catalytic performance. Furthermore, two distinct degradation pathways were inferred. Pathway Ⅰ (KMnO4-HT): toluene → benzyl → benzoic acid → carbonate → CO2 and H2O; Pathway ⅠⅠ (Mn-HT): toluene → benzyl alcohol → benzoic acid → phenol → maleic anhydride → CO2 and H2O. Fewer intermediates were detected on KMnO4-HT, indicating its stronger oxidation capacity of toluene, which was originated from the doping of K+ and the interaction between KOMn. More intermediates were observed on Mn-HT, which can be attributed to the weaker oxidation ability of pure Mn. The results indicated that the doping of K+ can improve the catalytic oxidation capacity of toluene, resulting in promoted degradation of intermediates during the oxidation of toluene.

Constructing a Titanium Silicon Molecular Sieve-Based Z-Scheme Heterojunction with Enhanced Photocatalytic Activity.

Titanium silicon molecular sieve (TS-1) is an oxidation catalyst that possesses a long lifetime of charge transfer excited state, high Ti utilization efficiency, large specific surface area, and good adsorption property; therefore, TS-1 acts as a Ti-based photocatalyst candidate. In this work, TS-1 coupled Bi2MoO6 (TS-1/BMO) photocatalysts were fabricated via a facile hydrothermal route. Interestingly, the optimized TS-1/BMO-1.0 catalyst exhibited a decent photodegradation property toward tetracycline hydrochloride (85.49% in 120 min) under the irradiation of full spectrum light, which were 4.38 and 1.76 times compared to TS-1 and BMO, respectively. The enhanced photodegradation property of the TS-1/BMO-1.0 catalyst could be attributed to the reinforced light-harvesting capacity of the photocatalyst, high charge mobility, and suitable band structure for tetracycline hydrochloride degradation. In addition, the mechanism of photocatalytic degradation of tetracycline hydrochloride by the TS-1/BMO-1.0 catalyst was reasonably proposed based on the band structure, trapping, and ESR tests. This research provided feasible ideas for the design and construction of high-efficiency photocatalysts for contaminant degradation.

Constructing surface oxygen defects at CuO-Co3O4 interface to boost toluene oxidation over CuO/Co3O4 catalysts.

As a typical heterogeneous catalytic process, the catalytic combustion of toluene over Co3O4-based catalysts is strongly depends on the surface properties of catalysts, especially the concentration of surface oxygen defects. Here, a novel way was proposed to construct chemically bonded CuO-Co3O4 interface by chemical deposition of CuO onto Co3O4 nanoflowers. The interfacial refinement effect between CuO and Co3O4 support disrupted the ordered atomic arrangement and created countless unsaturated coordination sites at CuO-Co3O4 interface, inducing a significant generation of surface oxygen defects. Surface-rich oxygen vacancies enhanced the capacity of 20%CuO/Co3O4-R to adsorb and activate oxygen species. Benefiting from this, 90 % toluene conversion was reached at 228 °C over 20%CuO/Co3O4-R, which was much lower than that over 20%CuO/Co3O4-S prepared by impregnation method and CuO/Co3O4-mix obtained by mechanically mixing way. In-situ DRIFTS analysis revealed that toluene could be directly decomposed into benzaldehyde at the highly defective CuO-Co3O4 interface, leading to toluene oxidation following the path of toluene → benzaldehyde → benzoate → maleic anhydride → water and carbon dioxide over 20%CuO/Co3O4-R, which was significantly different from decomposition mechanism over 20%CuO/Co3O4-S. Additionally, 20%CuO/Co3O4-R displayed terrific recyclability and outstanding stability, showing good application potential.

Establishing efficient toluene elimination over cobalt-manganese bimetallic oxides via constructing strong Co-Mn interaction.

Doping proves to be an efficacious method of establishing intermetallic interactions for enhancing toluene oxidation performance of bimetallic oxides. However, conventional bimetallic oxide catalysts are yet to overcome their inadequacy in establishing intermetallic interactions. In this work, the dispersion of Mn-Co bimetallic sites was improved by hydrolytic co-precipitation, strengthening the intermetallic interactions which improved the structural and physicochemical properties of the catalysts, thus significantly enhancing its catalytic behavior. MnCo-H catalysts fabricated by the hydrolytic co-precipitation method showed promising catalytic performance (T50 = 223 °C, T90 = 229 °C), robust stability (at least 100 h) and impressive water resistance (under 10 vol.% of water) for toluene elimination. Hydrolytic co-precipitation has been found to improve dispersion of MnCo elements and to enhance interaction between Co and Mn ions (Mn4+ + Co2+ = Mn3+ + Co3+), resulting in a lower reduction temperature (215 °C) and a weaker Mn-O bond strength, creating more lattice defects and oxygen vacancies, which are responsible for superior catalytic properties of MnCo-H samples. Furthermore, in situ DRIFTs showed that gaseous toluene molecules adsorbed on the surface of MnCo-H were continuously oxidized to benzyl alcohol → benzaldehyde → benzoate, followed by a ring-opening reaction with surface-activated oxygen to convert to maleic anhydride as the final intermediate, which further generates water and carbon dioxide. It was also revealed that the ring-opening reaction for the conversion of benzoic acid to maleic anhydride is the rate-controlling step. This study reveals that optimizing active sites and improving reactive oxygen species by altering the dispersion of bimetals to enhance bimetallic interactions is an effective strategy for the improvement of catalytic behavior, while the hydrolytic co-precipitation method fits well with this corollary.

Temporal and spatial dynamic changes of planktonic bacteria community structure in Li River, China: a seasonal survey.

A combined temporal and spatial research approach helps us to evaluate the ecological status of a river scientifically and comprehensively. To understand the response mechanisms of bacteria in the Li River to different environments, we conducted a 1-year study (2020-2021) and collected water samples from 18 sections of the river in October, January, April, and August. 16S sequencing was used to study the composition and structure of bacterial communities in Li River at different temporal and spatial scales. The results showed that NO3--N, TP, T, pH, and DO were significantly different on spatial and temporal scales. Alpha diversity of planktonic bacteria in Li River fluctuated significantly with the season, reaching its highest in summer. Proteobacteria remained the most dominant phylum in all seasons, but the differential microorganisms varied between seasons. Although the abundance of metabolic functions of planktonic bacteria did not show significant differences between seasons, we found that DO, TP, T, and COD were the key environmental factors affecting bacterial metabolism. In addition, the co-occurrence network analysis showed that the autumn network had a higher number of nodes and edges and exhibited a high degree of complexity, while the summer network had the highest degree of modularity and exhibited greater stability. These results deepen our knowledge of the response mechanisms of river microorganisms to temporal and spatial changes and provide a scientific reference for the study of river ecosystems.

The potential of a natural iron ore residue application in the efficient removal of tetracycline hydrochloride from an aqueous solution: insight into the degradation mechanism.

In the existing research, most of the heterogeneous catalysts applied in the activation of persulfate to degrade organic pollutants were synthesized from chemical reagents in the laboratory. In this paper, we have obtained a spent iron ore (IO) residue directly collecting from the iron ore plants, and efficiently activating peroxydisulfate (PS) to produce reactive free radicals. The experimental results demonstrated that the IO could effectively activate PS to degrade tetracycline hydrochloride (TCH), with TCH removal rate reaching up to 85.6% within 2 h at room temperature. The TCH removal rate was increased with increasing iron ore dosage, while the more acidic pH condition would be favorable to TCH removal process. The material characterization results demonstrated that the dominant components of IO were Fe3O4 and FeOOH. The transformation from Fe(II) to Fe(III) at the surface IO was observed after TCH degradation. What's more, the quenching experiment and EPR detection results confirmed that the sulfate radical (SO4•-) and hydroxyl radicals (•OH) would be acting as the main free radicals for TCH degradation. This study could not only explore a novel way to recycle the discarded iron ore, but also further expand its application in an effective activation of PS in an aqueous solution.

Design a flower-like magnetic graphite carbon microsphere for enhanced adsorption of 2,4-dichlorophenol.

2,4-Dichlorophenol (2,4-DCP) is a hazardous chlorinated organic chemical, so its removal is an important task to protect the whole ecosystem and human health. During the material preparation, the magnetic graphitic carbon adsorbent (HFMCM) with a sparse sheet-like stacking structure was formed by interlayer assembly of nickel hydroxide nanosheets and hydrothermal glucose carbon. The conditions for optimal performance of the adsorbent are 45 °C and pH 5. The maximum adsorption capacity of HFMCM-180 for 2,4-DCP is 147.06 mg·g-1. Adsorption behavior in accordance with Langmuir isothermal model and pseudo-second-order kinetic models. The adsorbent remains selective for 2,4-DCP in metal ion solutions. More than 75% of the adsorption capacity is maintained after five cycles of adsorption. Electrostatic interaction, hydrogen bonding, and π-π bonding play a major role in the adsorption of 2,4-DCP by HFMCM. The adsorbent was glucose as the carbon source, nickel sulfate as the magnetic source, and hexamethylenetetramine as the precipitant. Its carbonization after pretreatment with different hydrothermal temperatures resulted in the synthesis of flower-like graphitic carbon spheres with magnetic properties. The interconnected pore channels on the adsorbent surface conferred large specific surface area to the material. 2,4-DCP was efficiently adsorbed by π-π stacking, hydrogen bonding, and electrostatic attraction within the pore channels with low spatial potential resistance.

Synergetic effect between Fe and Ti species on Fe-Ti-Ox for hydrogen cyanide purification.

The Fe-Ti-Ox catalysts with the different Fe contents were used for the catalytic hydrolysis of hydrogen cyanide (HCN) in the presence of H2O, which investigated the roles of Fe chemical valence and oxygen species in HCN removal and the production (NH3 and CO). The results implied that more amounts of Fe3+ species over Fe-Ti-Ox could increase the catalytic hydrolysis activity of HCN while Fe2+ species contributed to the formation of NH3 at high temperatures. Furthermore, the abundance of surface oxygen species was in favour of the catalytic performance of HCN.

Occurrence, Profiles and Ecological Risk of Bisphenol Analogues in a Municipal Sewage Treatment Plant.

Due to the strict control on bisphenol A (BPA) in many countries, bisphenol analogues (BPs) are being widely used as alternative materials to manufacture epoxy resins and polycarbonate plastics, resulting in their occurrence in sewage treatment plants (STPs). In this study, the occurrence and distribution of 7 BPs in a large-scale STP in Beijing China was investigated. Wastewater samples were collected from the influents and effluents of each processing unit, and extracted by solid-phase extraction. Target compounds were quantified by ultra-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The total concentrations of seven BPs (ΣBPs) were 400.42 ± 48.12 ng/L in the raw sewage, 438.60 ± 46.50 ng/L in the primary effluent, 17.21 ± 13.12 ng/L in the secondary effluent, and 11.33 ± 4.84 ng/L in the tertiary effluent, respectively. Bisphenol S (BPS) and BPA were the predominant congener in raw sewage with an overall contribution of 29.32% and 70.22% to the ΣBPs, indicating that there was a large amount of BPS and BPA consumption in the study area. During a one-week sampling period, ΣBPs changed slightly at the same sampling site. It was found that high removal efficiencies were achieved for BPs in anoxic and oxic secondary clarifier treatment units, suggesting that biodegradation and sorption played major roles in BPs elimination in the STP. After tertiary treatment, all BPs except BPA were completely removed, suggesting the necessity to investigate the fate and toxicity of BPA in the aquatic environment.

Silicotungstic acid modified CeO2 catalyst with high stability for the catalytic combustion of chlorobenzene.

The catalysts' redox capacity and surface acidity was important during the catalytic combustion of chlorobenzene (CB). CeO2 showed great attractiveness due to its high oxygen storage capacity. Furthermore, the increase of acidity on the catalyst surface could improve the resistance to the chlorine poisoning. In this work, the silicotungstic (HSiW) modified CeO2 catalysts prepared by four cerium salts and exhibited the different morphologies and catalytic activity. The HSiW modified CeO2 catalyst prepared by Ce(CH3COO)3 (Cat-A) exhibited the best catalytic activity due to its abundant surface weak acid sites, more Ce3+ species and surface adsorption oxygen. The HSiW mainly located on the CeO2 (111) planes of the Cat-A, which was conducive to redox property of CeO2, thus promoting the deep oxidation of CB. Meanwhile the redox ability together with the weak acidity influenced the catalytic efficiency at low temperature. And the redox ability played a major role at high temperature. In addition, the Cat-A still possessed high stability and water resistance and maintained high activity after continuous catalytic oxidation of CB at 235 and 295 °C for 100h, exhibiting the possibility of industrial application.

Antimicrobial efficacy and mechanisms of silver nanoparticles against Phanerochaete chrysosporium in the presence of common electrolytes and humic acid.

In this study, influences of cations (Na+, K+, Ca2+, and Mg2+), anions (NO3-, Cl-, and SO42-), and humic acid (HA) on the antimicrobial efficacy of silver nanoparticles (AgNPs)/Ag+ against Phanerochaete chrysosporium were investigated by observing cell viability and total Ag uptake. K+ enhanced the antimicrobial toxicity of AgNPs on P. chrysosporium, while divalent cations decreased the toxicity considerably, with preference of Ca2+ over Mg2+. Impact caused by a combination of monovalent and divalent electrolytes was mainly controlled by divalent cations. Compared to AgNPs, however, Ag+ with the same total Ag content exhibited stronger antimicrobial efficacy towards P. chrysosporium, regardless of the type of electrolytes. Furthermore, HA addition induced greater microbial activity under AgNP stress, possibly originating from stronger affinity of AgNPs over Ag+ to organic matters. The obtained results suggested that antimicrobial efficacy of AgNPs was closely related to water chemistry: addition of divalent electrolytes and HA reduced the opportunities directly for AgNP contact and interaction with cells through formation of aggregates, complexes, and surface coatings, leading to significant toxicity reduction; however, in monovalent electrolytes, the dominating mode of action of AgNPs could be toxic effects of the released Ag+ on microorganisms due to nanoparticle dissolution.

The catalytic oxidation performance of toluene over the Ce-Mn-Ox catalysts: Effect of synthetic routes.

Ce-Mn-Ox catalysts were synthesized by impregnation (CM-IM), co-precipitation (CM-CP), citrate sol-gel (CM-SG) and hydrothermal (CM-HT) methods. The synthesis methods exhibited a great impact on the physicochemical properties of catalysts, resulting in different catalytic activity. The catalytic oxidation activity of toluene followed the sequence: CM-HT (T50: 234 °C; T90: 246 °C) > CM-SG (T50: 242 °C; T90: 249 °C) > CM-CP (T50: 243 °C; T90: 259 °C) > CM-IM (T50: 251 °C; T90: 261 °C), which was consistent with the sequence of surface relative percentage of Cov, Ce3+, Mn3+, Oα and r values. Among them, CM-HT showed the best catalytic oxidation performance of toluene due to more structural defects, oxygen vacancies, surface adsorption oxygen, normalized conversion rate and other active species. In addition, CM-HT catalysts showed reliable water resistance and good durability, implying the potential industrial application.

Alleviation of heavy metal and silver nanoparticle toxicity and enhancement of their removal by hydrogen sulfide in Phanerochaete chrysosporium.

Hydrogen sulfide (H2S), an important cellular signaling molecule, plays vital roles in mediating responses to biotic/abiotic stresses. Influences of H2S on metal removal, cell viability, and antioxidant response of Phanerochaete chrysosporium upon exposure to heavy metals and silver nanoparticles (AgNPs) in the present study were investigated. An enhancement in Pb(ΙΙ) removal with an increase in concentration of the H2S donor sodium hydrosulfide (NaHS) was observed, and the maximum removal efficiencies increased by 31% and 17% under 100 and 200 mg/L Pb(ΙΙ) exposure, respectively, in the presence of 500 µM NaHS. Application of 500 µM NaHS increased the cell viability by 15%-39% under Pb(II) stress (10-200 mg/L) with relative to the untreated control. Increase in total Ag uptake and cell survival was also elicited by NaHS in a concentration-dependent manner under AgNP stress. Meanwhile, activities of superoxide dismutase and catalase were significantly enhanced with the introduction of NaHS under stresses of Pb(II), Cd(II), Cu(II), Zn(II), Ni(II), and AgNPs. The inhibition in lipid peroxidation and oxidative stress was observed in P. chrysosporium cells exposed to these toxicants following NaHS pretreatment, which could be attributed to the upregulation in antioxidant enzymes. The results obtained suggest that H2S can alleviate heavy metals and AgNP-induced toxicity to P. chrysosporium and improve the removal efficiency of these toxicants from wastewater.

Antioxidative response of Phanerochaete chrysosporium against silver nanoparticle-induced toxicity and its potential mechanism.

Antioxidative response of Phanerochaete chrysosporium induced by silver nanoparticles (AgNPs) and their toxicity mechanisms were comprehensively investigated in a complex system with 2,4-dichlorophenol (2,4-DCP) and Ag+. Malondialdehyde content was elevated by 2,4-DCP, AgNPs, and/or Ag+ in concentration- and time-dependent manners within 24 h, indicating an increase in lipid peroxidation. However, beyond 48 h of exposure, lipid peroxidation was alleviated by upregulation of intracellular protein production and enhancement in the activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD). Comparatively, POD played more major roles in cell protection against oxidative damage. Furthermore, the dynamic change in reactive oxygen species (ROS) level was parallel to that of oxidized glutathione (GSSG), and ROS levels correlated well with GSSG contents (R2 = 0.953) after exposure to AgNPs for 24 h. This finding suggested that elimination of oxidative stress resulted in depletion of reduced glutathione. Coupled with the analyses of anoxidative responses of P. chrysosporium under the single and combined treatments of AgNPs and Ag+, HAADF-STEM, SEM, and EDX demonstrated that AgNP-induced cytotoxicity could originate from the original AgNPs, rather than dissolved Ag+ or the biosynthesized AgNPs.

Differential behaviors of silver nanoparticles and silver ions towards cysteine: Bioremediation and toxicity to Phanerochaete chrysosporium.

Potential transformations of silver nanoparticles (AgNPs) upon interaction with naturally ubiquitous organic ligands in aquatic environments influence their transport, persistence, bioavailability, and subsequent toxicity to organisms. In this study, differential behaviors of AgNPs and silver ions (Ag+) towards cysteine (Cys), an amino acid representative of thiol ligands that easily coordinate to Ag+ and graft to nanoparticle surfaces, were investigated in the aspects of bioremediation and their toxicity to Phanerochaete chrysosporium. Total Ag removal, 2,4-dichlorophenol (2,4-DCP) degradation, extracellular protein secretion, and cellular viability were enhanced to some extent after supplement of various concentrations of cysteine under stress of AgNPs and Ag+. However, an obvious decrease in total Ag uptake was observed after 5-50 µM cysteine addition in the groups treated with 10 µM AgNPs and 1 µM Ag+, especially at a Cys:Ag molar ratio of 5. More stabilization in uptake pattern at this ratio was detected under Ag+ exposure than that under AgNP exposure. Furthermore, in the absence of cysteine, all Ag+ treatments stimulated the generation of reactive oxygen species (ROS) more significantly than high-dose AgNPs did. However, cysteine supply under AgNP/Ag+ stress aggravated ROS levels, albeit alleviated at 100 µM Ag+, indicating that the toxicity profiles of AgNPs and Ag+ to P. chrysosporium could be exacerbated or marginally mitigated by cysteine. The results obtained were possibly associated with the lability and bioavailability of AgNP/Ag+-cysteine complexes.

Silver ion-enhanced particle-specific cytotoxicity of silver nanoparticles and effect on the production of extracellular secretions of Phanerochaete chrysosporium.

This study investigated the influence of silver ions (Ag+) on the cytotoxicity of silver nanoparticles (AgNPs) in Phanerochaete chrysosporium and noted the degree of extracellular secretions in response to the toxicant's stress. Oxalate production was elicited with moderate concentrations of 2,4-dichlorophenol (2,4-DCP) and AgNPs reaching a plateau at 10 mg/L and 10 µM, respectively. Increased oxalate accumulation was accompanied by higher activities of manganese peroxidase (MnP) and lignin peroxidase (LiP). However, the secretion of oxalate, MnP and LiP was significantly inhibited owing to Ag+ incorporation into AgNP solution. Production of extracellular polymeric substances (EPS) significantly elevated with an increase in 2,4-DCP concentrations; however, after 24 h of exposure to 100 mg/L 2,4-DCP, an obvious decrease in EPS occurred, indicating that part of EPS could be consumed as carbon and energy sources to ameliorate biological tolerance to toxic stress. Furthermore, AgNP-induced "particle-specific" cytotoxicity was substantially enhanced with additional Ag+ as evidenced by its significant negative impact on cellular growth, plasma membrane integrity, and morphological preservation compared with AgNPs at equal Ag concentration.

Toxicity mechanisms and synergies of silver nanoparticles in 2,4-dichlorophenol degradation by Phanerochaete chrysosporium.

Mechanisms of silver nanoparticles-mediated toxicity to Phanerochaete chrysosporium and the influence of silver nanoparticles (AgNPs) on the biodegradation of 2,4-dichlorophenol (2,4-DCP) have been systematically investigated. AgNPs at low doses (0-60µM) have greatly enhanced the degradation ability of P. chrysosporium to 2,4-DCP with the maximum degradation rates of more than 94%, exhibiting excellent synergies between AgNPs and P. chrysosporium in the degradation of 2,4-DCP. Meanwhile, removal of total Ag was also at high levels and highly pH dependent. However, significant inhibition was highlighted on 2,4-DCP biodegradation and Ag removal upon treatment with AgNPs at high doses and AgNO3 at low-level exposure. Results also suggested that AgNPs-induced cytotoxicity could arise from the "Trojan-horse" mechanism executing particle effects, ion effects, or both, ruling out extracellularly released Ag+. Moreover, under relatively low concentrations of AgNPs exposure, 2,4-DCP was broken into linear chain organics, and eventually turned into CO2 and H2O through reductive dechlorination and reaction with hydroxyl radicals. FTIR analysis showed that amino, carboxyl, carbonyl, and sulfur-containing functional groups played crucial roles in Ag transportation and the reduction of Ag+ to Ag0.

Activity and hydrothermal stability of CeO2-ZrO2-WO3 for the selective catalytic reduction of NOx with NH3.

A series of CeO2-ZrO2-WO3 (CZW) catalysts prepared by a hydrothermal synthesis method showed excellent catalytic activity for selective catalytic reduction (SCR) of NO with NH3 over a wide temperature of 150-550°C. The effect of hydrothermal treatment of CZW catalysts on SCR activity was investigated in the presence of 10% H2O. The fresh catalyst showed above 90% NOx conversion at 201-459°C, which is applicable to diesel exhaust NOx purification (200-440°C). The SCR activity results indicated that hydrothermal aging decreased the SCR activity of CZW at low temperatures (below 300°C), while the activity was notably enhanced at high temperature (above 450°C). The aged CZW catalyst (hydrothermal aging at 700°C for 8 hr) showed almost 80% NOx conversion at 229-550°C, while the V2O5-WO3/TiO2 catalyst presented above 80% NOx conversion at 308-370°C. The effect of structural changes, acidity, and redox properties of CZW on the SCR activity was investigated. The results indicated that the excellent hydrothermal stability of CZW was mainly due to the CeO2-ZrO2 solid solution, amorphous WO3 phase and optimal acidity. In addition, the formation of WO3 clusters increased in size as the hydrothermal aging temperature increased, resulting in the collapse of structure, which could further affect the acidity and redox properties.

Polyvinyl alcohol-immobilized Phanerochaete chrysosporium and its application in the bioremediation of composite-polluted wastewater.

A novel biosorbent, polyvinyl alcohol (PVA)-immobilized Phanerochaete chrysosporium, was applied to the bioremediation of composite-polluted wastewater, containing both cadmium and 2,4-dichlorophenol (2,4-DCP). The optimum removal efficiency achieved was 78% for Cd(II) and 95.4% for 2,4-DCP at initial concentrations of 20 mg/L Cd(II) and 40 mg/L 2,4-DCP. PPBs had significantly enhanced the resistance of P. chrysosporium to 2,4-DCP, leading to the degradation rates of 2,4-DCP beyond 90% with varying initial 2,4-DCP concentrations. This research demonstrated that 2,4-DCP and secreted proteins might be used as carbon and nitrogen sources by PVA-immobilized P. chrysosporium beads (PPBs) for Cd(II) removal. Fourier transform infrared spectroscopy analysis showed that hydroxyl and carboxyl groups on the surface of PPBs were dominant in Cd(II) binding. The mechanism underlying the degradation of 2,4-DCP into fumaric acid and 1-hexanol was investigated. The adsorption-desorption studies indicated that PPBs kept up to 98.9% of desorption efficiency over three cycles.