Phenol Uptake Research Articles

Feasibility of Activated Carbon Production from Biological Sludge by Chemical Activation with ZnCl2 and H2SO4

The transformation of surplus biological sludge to activated carbon by chemical activation with H2SO4 and ZnCl2 was investigated. The best result was obtained by pyrolysis and activation at 500°C for one hour with H2SO4. The surface area of the product was 257 m2 per gram. The quality of the carbons was tested for the aqueous phase phenol uptake and compared with a commercial activated carbon.

Macro‐kinetic investigation on phenol uptake from air by biofiltration: Influence of superficial gas flow rate and inlet pollutant concentration

Macro‐kinetic investigation on phenol uptake from air by biofiltration: Influence of superficial gas flow rate and inlet pollutant concentration

Phenol removal by Eichhornia crassipes in the presence of trace metals

The removal of phenols in the presence of copper and zinc by the aquatic weed, Eichhornia crassipes was investigated in order to assess its ability to clean up industrial wastewaters. Results indicate that Eichhornia has tremendous capacity to absorb phenolic compounds as well as Cu and Zn simultaneously from test solutions containing these substances. The presence of Cu or Zn resulted in decreased phenol uptake during the first 0.5 d, while the presence of Cu and Zn in combination resulted in higher phenol uptake. After 1 d exposure, however, little or no differences could be discerned. Similarly, absorption of Cu and Zn in the presence of phenols did not seem to be adversely affected by different combinations of Cu/Zn concentrations. In fact, some synergistic effect could be detected between Cu and Zn absorption by Eichhornia crassipes. Bioassays involving filtered Eichhornia root extract indicated that phenol was also removed by the aqueous root extracts indicating that cellular constituents of roots were involved in the process. The corresponding K m and V max for the enzyme-like substance were 0.58 and 8.97 mM phenol/h/g fresh root tissue, respectively.

Sorption of phenol by selected biopolymers: isotherms, energetics, and polarity

The behavior of phenol in the terrestrial environment is strongly regulated by its reaction with soil components. We report here on the uptake of phenol by soil minerals (goethite, kaolinite, and montmorillonite) and by organics that may occur naturally in or be added to soil (two lignins, chitin, cellulose, collagen, and activated carbon). Our objectives were to determine the energetics and capacity for their uptake of phenol using batch equilibration, calorimetry, and CPMAS 13 C NMR and to evaluate the relation of organic carbon referenced sorption coefficient (K oc ) with the polarity of biopolymers. The biopolymers sorbed 2-45-fold more phenol than did the minerals

Sorption of organics from aqueous solution onto polymeric resins

The uptake of phenol, toluene, chlorobenzene, and benzoic acid by several polymeric resins and activated carbon was investigated experimentally. Presentation of the sorption data in terms of the number of sorbed monolayers and fractional pore volume filled indicated that, for the polymeric resins, solute uptake cannot be viewed as only a surface adsorption phenomenon. It is suggested that the aqueous phase uptake of phenol, toluene, chlorobenzene, and benzoic acid by the polymeric resins is attributable, in part, to solute absorption. The present study also suggests that solute uptake is affected by the swelling of some of the polymeric resins in water.

Uptake of phenol by the phenol-metabolizing bacteria of a stable, strictly anaerobic consortium

Phenol was absorbed unspecifically by active and by inactivated cells of a strictly anaerobic, phenol-degrading consortium to reach about twice the concentration of the medium. The absorption was temperature-dependent. A Q10 of 1.7 was determined, indicating that accumulation was due to diffusion or facilitated diffusion and not to an active transport process. At increasing phenol concentration in the medium, concentrated cell suspensions adsorpted phenol proportionally until saturation was reached at about 25 nmol phenol/mg cell dry weight. At a phenol concentration in the medium of 2 mm, the washed cell pellet contained 3.5 mm phenol. Under conditions that allowed phenol metabolism (presence of CO2), [14C]4-hydroxybenzoyl-coenzyme A and [14C]4-hydroxybenzoate were found as early intermediates of [U-14C]phenol degradation for the first time. [14C]Benzoate was excreted stoichiometrically if phenol degradation to acetate was prevented by H2. Absolutely no 14C-label was found in the phenylphosphate peak after HPLC separation, which excluded phosphorylation of phenol during uptake or during degradation in the cells.

Dynamics of phenol degradation by Pseudomonas putida

Pure cultures of Pseudomonas putida (ATCC 17484) were grown in continuous culture on phenol at dilution rates of 0.074-0.085 h(-1) and subjected to step increases in phenol feed concentration. Three distinct patterns of dynamic response were obtained depending on the size of the step change used: low level, moderate level, or high level. During low level responses no accumulations of phenol or non-phenol, non-glucose-dissolved organic carbon, DOC(NGP), were observed. Moderate level responses were characterized by the transient accumulation of DOC(NGP) with a significant delay prior to phenol leakage. High level responses demonstrated a rapid onset of phenol leakage and no apparent accumulations of DOC(NGP). The addition of phenol to a continuous culture of the same organism on glucose did not result in transient DOC(NGP) accumulations, although transient phenol levels exceeded 90 mg l(-1). These results were consistent with intermediate metabolite production during phenol step tests coupled with substrate-inhibited phenol uptake and suggested that traditional kinetic models based on the Haldane equation may be inadequate for describing the dynamics of phenol degrading systems.

Toxicokinetics of xenobiotics in zebrafish—Comparison between tap and river water

1. 1. Uptake and elimination of lindane, 3,4-dichloroaniline, phenol and 4-nitrophenol by the zebrafish Brachydanio rerio were investigated in tap water and in water of the river Rhine. 2. 2. The differences in bioconcentration of chemicals between the two water types did not exceed a factor of 2.5. 3. 3. Elimination kinetics were comparable in tap and river water. 4. 4. It can be concluded that water of the river Rhine does not influence the kinetics of the investigated xenobiotics.

A low cost adsorbent from spent bleaching earth. I—the selection of an activation procedure

AbstractThe conversion of a spent filter cake from the edible oil industry to a heterogeneous clay‐carbon adsorbent is reported. Chemical and physical activation procedures have been applied and the resulting materials screened by carbon content and aqueous phenol uptake. Full adsorption isotherms are plotted for sorbents with high phenol capacities and their adsorptive behaviour is modelled to the Freundlich and Langmuir isotherms.

Anaerobic degradation of phenol using an acclimated mixed culture

Anaerobic methanogenesis of phenol using mixed cultures derived from cow dung and municipal sewage sludge and adapted to phenol was done in batch reactors. The phenol degradation rate depended on the period in which the culture was acclimated to phenol. Interference in phenol uptake by glucose was observed. Consumption of both phenol and acetic acid was observed when an acetate-adapted culure was used. A phenol-acclimated culture was able to degrade dihydroxy phenols thus indicating the feasibility of cross-acclimation.

Reactivity Toward Phenol of Lignin from the Hydrolysis of Sweetgum Wood with Concentrated Sulfuric Acid

Abstract Sweetgum wood was hydrolyzed at 20°C and 50°C for different time periods with 68% sulfuric acid. The lignin residues obtained were subjected to a phenolation reaction. For lignin prepared at the lower temperature the maximum phenol uptake was 9.5%, and at the higher temperature only 5–6%. When wood prehydrolyzed with dilute acid was used the phenol uptake rose to 12.5%. However, all the sulfuric acid hydrolysis lignins showed much lower reactivity toward phenol than the 20% phenol uptake exhibited by lignin isolated using concentrated hydrochloric acid.

Induction of high-affinity phenol uptake in glycerol-grown Trichosporon cutaneum

Two uptake systems for phenol are identified in Trichosporon cutaneum. One is an inducible, high-affinity system, sensitive to protonophores. It is induced coordinately with phenol hydroxylase but can operate independently of phenol metabolism. The other is a constitutive, low-affinity system with different specificity and different pH optimum. It is not sensitive to protonophores.

Oxidation of an inhibitory substrate by washed cells (oxidation of phenol by Pseudomonas putida)

The specific uptake rate of phenol by washed cells of Pseudomonas putida grown on phenol in steady-state continuous culture at various dilution rates was studied. The Monod-Haldane-type equation was applied to fit the data and the best kinetic parameters were determined by nonlinear least-squares techniques. The values of the kinetic parameters were found to increase monotonically with the phenol concentration in the original chemostat. The relations between the values of kinetic parameters and phenol concentration in the chemostat were described by empirical equations. Then the equation governing the instant uptake of phenol by microorganisms in chemostat in the high conversion range of phenol was proposed. This equation together with the mass balance equations can be used to determine the stability range of continuous stirred tank biochemical reactors (CSTBR) utilizing phenol.

Transpiration Effect on the Uptake and Distribution of Bromacil, Nitrobenzene, and Phenol in Soybean Plants

AbstractThe influence of transpiration rate on the uptake and translocation of two industrial waste compounds, phenol and nitrobenzene, and one pesticide, 5‐bromo‐3‐sec‐butyl‐6‐methyluracil (bromacil), was examined. Carbon‐14 moieties of each compound were provided separately in hydroponic solution to mature soybean plants [Glycine max (L.) Merr. dwarf cultivar Fiskeby v] maintained under three humidity conditions. The uptake of each compound was determined by monitoring the removal of 14C from the hydroponic solution. The extent to which 14C was adsorbed to roots and translocated to plant shoots and leaves was examined by assaying root and shoot parts for 14C. Bromacil was taken up slower than the other chemicals, had the most 14C translocated to the shoot, and the amount translocated to the shoot responded directly to the rate of transpiration. In contrast, both phenol and nitrobenzene were rapidly lost from solution and bound to the roots. Less than 1.5% of the 14C from phenol or nitrobenzene was translocated to the plant shoots. Increased transpiration rates had little influence on root binding of 14C; however, increasing transpiration rate from low to medium was associated with an increased uptake of nitrobenzene. The three chemicals studied have similar Log Kow values, but their interactions with soybean were not the same. Thus, despite the usefulness of the octanol/water partitioning coefficient in predicting the fate of organic chemicals in animals and in correlating with root binding and plant uptake for many pesticides, log Kow may not be equally useful in describing uptake and binding of nonpesticide chemicals in plants.

Bacterial Growth in Mixed Cultures on Dissolved Organic Carbon from Humic and Clear Waters

Interactions between bacterial assemblages and dissolved organic carbon (DOC) from different sources were investigated. Mixed batch cultures were set up with water from a humic and a clear-water lake by a 1:20 dilution of the bacterial assemblage (1.0 mum of prefiltered lake water) with natural medium (sterile filtered lake water) in all four possible combinations of the two waters and their bacterial assemblages. Bacterial numbers and biomass, DOC, thymidine incorporation, ATP, and uptake of glucose and phenol were followed in these cultures. Growth curves and exponential growth rates were similar in all cultures, regardless of inoculum or medium. However, bacterial biomass produced was double in cultures based on water from the humic lake. The fraction of DOC consumed by heterotrophic bacteria during growth was in the same range, 15 to 22% of the total DOC pool, in all cultures. Bacterial growth efficiency, calculated from bacterial biomass produced and DOC consumed, was in the order of 20%. Glucose uptake reached a peak during exponential growth in all cultures. Phenol uptake was insignificant in the cultures based on the clear-water medium, but occurred in humic medium cultures after exponential growth. The similarity in the carbon budgets of all cultures indicated that the source of the bacterial assemblage did not have a significant effect on the overall carbon flux. However, fluxes of specific organic compounds differed, as reflected by glucose and phenol uptake, depending on the nature of the DOC and the bacterial assemblage.

Lethal and Sublethal Effects of Chlorine, Phenol, and Chlorine-Phenol Mixtures on the Mud Crab, Panopeus herbstii

The mud crab, Panopeus herbstii, was acutely exposed (96-hr) to chlorine-produced oxidants (CPO), phenol, and a CPO-phenolic mixture (1:1) to determine lethal and sublethal effects. The 96-hr (LC50) values were determined for each individual compound and mixture. Additionally, whole-animal respiration rates were measured following acute exposure to sublethal concentrations of each compound or mixture. Phenol uptake/depuration rates were measured in the phenol and CPO-phenol mixture concentrations. Results indicated 96-hr LC50 values of 1.06 mg/L for CPO (fiducial limits (FL) = 0.53-2.01 mg/L), 52.8 mg/L for phenol (FL = 45.6-64.5 mg/L), and 184.7 mg/L total toxicant units (TTU) for the CPO-phenol mixture (FL = 143.7-250.2 mg/L TTU). Statistical analysis indicated that the acute toxicity of the CPO-phenol mixture was less than additive. Sublethal studies indicated that only acute exposure to sublethal concentrations of CPO caused altered respiration rates. After 96-hr depuration, metabolic rates in all CPO-exposure crabs generally returned to control rates. Uptake/depuration rate studies indicated significantly lower phenol uptake rates in crabs exposed to the CPO-phenol mixture. These findings suggest that the less-than-additive toxicity of the CPO-phenol mixture may result from lowered uptake/depuration rate kinetics and indicate that the discharge of chlorinated-phenolic waste may not result in additive and/or synergistic interactions, but rather in less-than-additive effects on decapod aquatic species.

Lethal and sublethal effects of chlorine, phenol, and chlorine-phenol mixtures on the mud crab, Panopeus herbstii.

The mud crab, Panopeus herbstii, was acutely exposed (96-hr) to chlorine-produced oxidants (CPO), phenol, and a CPO-phenolic mixture (1:1) to determine lethal and sublethal effects. The 96-hr (LC50) values were determined for each individual compound and mixture. Additionally, whole-animal respiration rates were measured following acute exposure to sublethal concentrations of each compound or mixture. Phenol uptake/depuration rates were measured in the phenol and CPO-phenol mixture concentrations. Results indicated 96-hr LC50 values of 1.06 mg/L for CPO (fiducial limits (FL) = 0.53-2.01 mg/L), 52.8 mg/L for phenol (FL = 45.6-64.5 mg/L), and 184.7 mg/L total toxicant units (TTU) for the CPO-phenol mixture (FL = 143.7-250.2 mg/L TTU). Statistical analysis indicated that the acute toxicity of the CPO-phenol mixture was less than additive. Sublethal studies indicated that only acute exposure to sublethal concentrations of CPO caused altered respiration rates. After 96-hr depuration, metabolic rates in all CPO-exposure crabs generally returned to control rates. Uptake/depuration rate studies indicated significantly lower phenol uptake rates in crabs exposed to the CPO-phenol mixture. These findings suggest that the less-than-additive toxicity of the CPO-phenol mixture may result from lowered uptake/depuration rate kinetics and indicate that the discharge of chlorinated-phenolic waste may not result in additive and/or synergistic interactions, but rather in less-than-additive effects on decapod aquatic species.

Application of current chemical concepts to metal-hematein and-brazilein stains

Current chemical concepts were applied to Weigert's, M. Heidenhain's and Verhoeff's iron hemateins, Mayer's acid hemalum stain and the corresponding brazilein compounds. Fe bonds tightly to oxygen in preference to nitrogen and is unlikely to react with lysyl and arginyl groups of proteins. Binding of unoxidized hematoxylin by various substrates has long been known to professional dyers and was ascribed to hydrogen bonding. Chemical data on the uptake of phenols support this theory. Molecular models indicate a nonplanar configuration of hematoxylin and brazilin. The traditional quinonoid formula of hematein and brazilein was revised. During chelate formation each of the two oxy- groups of the dye shares an electron pair with the metal and contributes a negative charge to the chelate. Consequently, the blue or black 2:1 (dye:metal) complexes are anionic. Olation of such chelates affects the staining properties of iron hematein solutions. The color changes upon oxidation of hematoxylin, reaction of hematein with metals, and during exposure of chelates to acids can be explained by molecular orbital theory. Without differentiation or acid in dye chelate solutions, staining patterns are a function of the metal. Reactions of acidified solutions are determined by the affinities of the dye ligands. Brazilein is much more acid-sensitive than hematein. This difference can be ascribed to the lack of a second free phenolic -OH group in brazilein, i.e. one hydrogen bond is insufficient to anchor the dye to tissues. Since hematein and brazilein are identical in all other respects, their differences in affinity cannot be explained by van der Waals, electrostatic, hydrophobic or other forces.

Uptake of phenol by Trichosporon cutaneum

The soil yeast Trichosporon cutaneum, which is distinguished by having a strictly oxidative metabolism, can be induced to utilize phenol as a sole carbon source. The present paper shows that such phenol-induced cells contain a specific, energy-dependent uptake system for phenol. Phenol uptake is not directly linked to its o-hydroxylation inside the cell, the first step of phenol metabolism. The Km for uptake is 235 +/- 30 microM, that for hydroxylation only 4.5 +/- 0.5 microM. Further, the phenol analog 2,6-dimethylphenol, which can not be hydroxylated, competes with phenol for the uptake system. The pH dependence of uptake indicates that phenolate is an essential form during the uptake process. The energy requirement for phenol uptake is indicated by effects of various inhibitors of energy generation, including proton-conducting uncouplers. Direct monitoring of proton movements in a pH-stat during phenol uptake indicates a phenol-proton symport. One proton is cotransported with every phenol molecule. Phenol competes with the uptake of sucrose and glycerol by cells grown on these substrates. Under such conditions the uptake of phenol seems to proceed through a different system, with lower affinity for phenol than in phenol-grown cells.

Synthesis, characterization, and applications of condensate porous polymeric sorbents based on m‐phenylenediamine

AbstractA few condensate porous polymeric sorbents were synthesized based on m‐phenylenediamine–melamine–formaldehyde polycondensation using suitable porosogenic agents. They were characterized for ion‐exchange capacity, bulk density, solvent uptake, pH–titration curve, and rate of exchange. Their surface characteristics were studied using mercury porosimetry, scanning electron microscopy, and the uptake of fast green FCF dye. A selected sorbent was studied for the uptake of phenol in static and dynamic conditions, and the uptake performance was compared with commercially available porous anion exchanger Amberlite‐IRA 93. Results obtained clearly indicated that modified products have higher pore volume, higher surface area, and good ion‐exchange kinetics as compared to the conventional gel type product.