STIMULATION OF PETROLEUM HYDROCARBON DEGRADATION IN SOIL
GAYATHRI.M
DATE OF SUBMISSION:19-12-2017.
ABSTRACT:
Hydrocarbon are mainly the pollutants from oil refineries and oil spills. These pollutants can be degraded by a consortium or cocktail of microorganisms e.g. pseudomonas, Corynebacterium, Arthobacter, Mycobacterium and nocardia. Biodegradation has at least three outcomes (1) a minor change in an organic molecule, leaving the main structure still intact;(2) Fragmentation of a complex organic molecule in such a way that the fragments could be reassembled to yield the original structure; and (3) complete mineralisation, which is transformation of organic molecules to inorganic forms. In the laboratory experiments,
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There are several 100 individual components in every crude oil and the composition of each varies with its origin. Most xenobiotic pollutants can be regarded as substituted (or) modified hydrocarbons. Susceptibility to biodegradation varies with type and size of the hydrocarbon molecule. Fuel and lubricating oil spills have become a major environmental hazard to-date. The extent of hydrocarbon biodegradation in contaminated soils is critically dependent upon three factors: a) the creation of optimal environmental conditions to stimulate biodegradative activity, b) the predominant Petroleum hydrocarbon types in the contaminated matrix and c) the bioavailability of the contaminants to microorganisms. The Petroleum hydrocarbon degradation is also affected by the molecular composition of the hydro carbons. Microorganisms with the ability to degrade crude oil are ubiquitously distributed in soil and mine environments. Dehydrogenase enzyme involves in this to remove the oxidative substrate, and has been found in correlation with the oxygen uptake and organic substrate removal rates in aerobic …show more content…
Samples were transported in coolers to the laboratory, and stored at −20°C until they were analysed. Soil samples were sieved moist using a 2-mm mesh screen and thoroughly mixed. 10 g of soil was added to 95 ml deionized water containing 2 drops of Tween 80 and then was incubated and shaked for 30 min at room temperature. The mixture prepared is called soil solution. A 100 ml Erlenmeyer (flask 1) was prepared containing 2.5 ml soil solution and 95 ml of mineral salt medium (MSM) (KH2PO4, 1.52 g; Na2HPO4, 2.44 g; CaCl2.2H2O, 0.50 g; MgSO4.7H2O, 0.20 g; (NH4)2SO4, 0.50 g; trace element, 10ml) and 2.5ml of synthetic mixture of petroleum hydrocarbons (gas oil, kerosene, furnace oil; 1:1:0.1) as sole source of carbon. The flask was incubated at 22 ± 2 o C. After 15 days, 2.5 ml of flask1 was transferred to a second flask (flask 2) with the same condition as flask 1. These incubating -transferring were repeated for 4 times. The experiments were carried out with soil from an uncontaminated area around were the sample is collected. The soil samples were sieved by a 2-mm screen and were sterilized three times by autoclaving at 200 o C for 30 min followed by incubation for 24 h at 37 o C. Six 250 ml Erlenmeyer flasks were prepared for each of the soils
In the first part of the experiment, Part A, the standard solutions were prepared. As a whole, the experiment was conducted by four people, however, for Part A, the group was split in two to prepare the two different solutions. Calibrations curves were created for the standard solutions of both Red 40 and Blue 1. Each solution was treated with a serial 2-fold dilution to gain different concentrations of each solution.
Introduction The purpose of this Lab was to identify the density of the unidentified object and determine what substance the unidentified object given by the teacher was. The density calculated in the experiment will stay the same because the density of the unidentified object will stay constant. The Independent Variable of this experiment was the calculated density and the unidentified object given. The Dependant Variable for this experiment was the density.
This demonstrated our ability to both create a solution, and correctly interpret the task at hand. In the second lab, Introduction to General Chemistry, An Experimental Tour, we were asked to accurately record data,
Using the pipette, 25 mL of the distilled water from the Erlenmeyer flask was filled and dispensed in the beaker. The mass of the beaker containing the water was measured and recorded. In addition, the volume of the water transferred was calculated using the mass and density from the Density of Water table. Finally, the difference between the observed and calculated volumes of water was
Purpose/ Methods The purpose of this experiment was to determine the mass percent Cu2+ in a mineral sample (Malachite), and a rock sample (copper ore). Through the process of spectroscopy, the students were able to determine the percent of copper that each sample yielded. The students were also able to apply the information to the theoretical value of copper in malachite to determine the percent error of the mineral mass percent. Furthermore, the methods used in the experiment provide insight into how mining companies determine whether a copper ore mining site will be profitable or not.
Procedure and Observations To begin the lab, first all the correct equipment and materials had to be collected
To prepare the solutions a 70% ethanol solution was used to make 40%. This was calculated using the C1V1=C2V2 formula. A photo spectrometer was used to measure, in arbitrary units, the change in membrane permeability of the B. Vulgaris cells. To begin, the B. Vulgaris samples were put into vials containing the distilled water, 40% and 70% Ethanol solutions. As soon as the B. Vulgaris samples were added to the vials a time zero sample was taken from the vials.
So as they were developing this experiment they needed to gather
8) Explain how each experiment type (question 7) differs from the
Materials and Methods The chemicals used to perform this experiment were distilled water, sodium chloride (NaCl), ice,
The main strength of conducting this experiment is that is shows the behavior exactly as it occurs in the real world.
This experiment has to be carried out carefully
Parents know that baby oil is a necessity if you have a baby. It helps keep their skin soft year-round. However, baby oil is not only good for infants. It can also be used for many other things. You can prevent frost bite by applying it to the exposed area of the skin.
Nowadays, environmental degradation has become an important issue. This is because environmental degradation is one of the largest threats that is being looked at in the world today. This is because of the depletion of important resources such as air, water, and soil; the destruction of ecosystems; habitat destruction; the extinction of wildlife; and pollution. To limit the impact of these situations, it is important to know the possible side-effects of environmental degradation. Therefore, there are several causes and negative effects of environmental degradation provided in this essay with some recommendations to prevent it.