Does toluene degrade?
The specific degradation rate of toluene was 2.38 µmol/g-DCW/hr when toluene alone was present. The presence of benzene, ethylbenzene, or xylene with tolu- ene in binary mixtures had a positive effect on toluene degradation rates: 3.79, 3.71, and 3.98 µmol/g-DCW/hr, respectively.
Which bacteria can degrade toluene?
They isolated eight to 10 strains of bacteria and found that a particular bacteria Acinetobacter junii showed good degrading potential — about 80% of toluene (50 ppm) in a liquid medium was degraded within 72 hours.
What is aerobic degradation?
Aerobic biodegradation is the breakdown of organic contaminants by microorganisms when oxygen is present. Many organic contaminants are rapidly degraded under aerobic conditions by aerobic bacteria called aerobes. Aerobic bacteria (aerobe) have an oxygen based metabolism.
What are the products of aerobic degradation?
The end products of an aerobic process are primarily carbon dioxide and water which are the stable, oxidised forms of carbon and hydrogen. If the biodegradable starting material contains nitrogen, phosphorus and sulfur, then the end products may also include their oxidised forms- nitrate, phosphate and sulfate.
What do you mean by anaerobic degradation?
Anaerobic degradation is a series of processes in which microorganisms break down biodegradable material in the absence of oxygen. It is widely used to treat wastewater sludge and biodegradable waste because it provides volume and mass reduction of the input material.
What is the pH of toluene?
The range of the pH values of toluene and [Bmim][BF4] and [Bmim][PF6] were from (3.16 to 4.63) and (5.57 to 7.55), respectively.
How does an aerobic digester work?
Aerobic digestion stabilizes excess biological solids by the oxidation of cellular organic matter through endogenous metabolism. Conventional aerobic digestion employs aeration of primary and secondary clarifier underflow in one or more completely mixed aeration basins.
Is toluene biodegradable?
Batch biodegradation of toluene was carried out at various initial concentrations ranging from 50 to 500 mg l−1 at room temperature (28 °C) with initial a pH value of 6.85 maximum observed specific growth rate was 0.062 h−1 and maximum removal efficiency of toluene was 84% at 100 mg l−1.
What does benzene degrade into?
Benzene‐degrading organisms contain mono‐ or dioxygenases which activate the aromatic nucleus by introducing molecular oxygen to yield phenol or cis‐benzene dihydrodiol, compounds that are further oxidized to catechol (Gibson and Parales, 2000; Tao et al., 2004).
Which of the following is an anaerobic microbe that can degrade benzene anaerobically?
Dechloromonas strain RCB has been shown to be capable of anaerobic degradation of benzene coupled to nitrate reduction. As a continuation of these studies, the metabolic versatility and hydrocarbon biodegradative capability of this organism were investigated.
What is the Iupac name for toluene?
methylbenzene
Toluene (), also known as toluol (), is an aromatic hydrocarbon. It is a colorless, water-insoluble liquid with the smell associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) attached to a phenyl group. As such, its systematic IUPAC name is methylbenzene.
Is benzene biodegradable?
Under denitrifying conditions there was apparent biodegradation of benzene, toluene, ethyl-benzene, m-xylene and p-xylene but o-xylene was not degraded. Degradation under denitrifying conditions occurred at a much slower rate than under oxygenated conditions.
Is benzene carcinogenic?
The Department of Health and Human Services (DHHS) has determined that benzene causes cancer in humans. Long-term exposure to high levels of benzene in the air can cause leukemia, cancer of the blood-forming organs.
How do you break down benzene?
Scientists have demonstrated a way to use a metallic complex, trinuclear titanium hydride, to accomplish the task of activating benzene by breaking the aromatic carbon-carbon bonds at relatively mild temperatures and in a highly selective way.
Which bacteria can degrade naphthalene?
Recently, a number of oxic/anoxic bacteria have been used to biodegrade naphthalene with several pathways and metabolic diversities described [11]. Bacteria such as Pseudomonas putida, Rhodococcusopacus, Mycobacterium sp., Nocardia otitidiscaviarum, and Bacillus pumilus have been reported to biodegrade naphthalene.
Which bacteria is used in biogas?
Denitrifying bacteria- These bacteria convert the nitrates in the soil to free nitrogen. Thus the correct answer is (A) Methanogen is used in gobar gas plants. Additional Information: Biogas is used for heating purposes like cooking, running gas engines.
What is the difference between benzene and toluene?
Benzene is an aromatic hydrocarbon with the molecular formula C6H6 while toluene is a benzene derivative with the molecular formula C7H8. The key difference between benzene and toluene is their structure; toluene has a methyl group attached to the benzene ring while benzene has no methyl groups attached.
How can benzene and toluene be biodegraded?
Recently, we have reported biodegradation of benzene, toluene, ethylbenzene, and xylene (BTEX) by mixed cultures obtained from an oil–brine soil [ [ 9 ].
How are benzene and toluene degraded in p.putida F1?
Both systems, immobilized and suspended cells of P. putida F1, were able to completely degrade benzene and toluene from initial concentrations of 15, 30, 60, and 90 mg l −1. An inhibitory effect of the intermediary catechol from benzene degradation was observed in suspended cultures but it was not presented in the immobilized system.
What is the rate of biodegradation of benzene?
Biodegradation of benzene was evaluated at different temperatures ranging from 5 to 60 °C (Fig. 2). Although the enrichment was developed and maintained at 30 °C, degradation of benzene occurred at a maximum rate of 6.44 and 5.96 μmol/bottle/day at 37 and 45 °C, respectively.
Where are benzene, toluene, and o-xylene found?
1. Introduction Benzene, toluene, and o-xylene (BTX) are polluting agents derived from petroleum-like refining fuels, coatings, colorants, and solvents; they are commonly found in polluted soil and groundwater.
