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The present study describes the influence of the concentration of lignin when used as a filler in polyurethane foam for crude oil sorption. The foams (lignin 0-20wt%) were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis, contact angle and density. The FTIR analysis confirmed urethane linkage formation, showing that the chemical structure of the polymer was preserved, despite the addition of different lignin concentrations. Thermogravimetric analysis showed that the presence of lignin has altered the onset temperature (T onset ) of the foams, decreasing as the concentration of lignin is increased. The contact angle analysis showed a decrease in the hydrophobicity of the foams with increasing lignin concentration. All modified foams showed an improvement in the oil sorption capacity in a PUF/oil/water system, and the PUF-10 showed an improvement of about 35.5% compared to the PUF-blank. The Langmuir isotherm showed a better fit to the data and predicted a maximum oil adsorption of 28.9gg -1 by the PUF-10. The ΔG° value of -4.4kJmol -1 indicated that crude oil adsorption process by PUF-10 was spontaneous. The results of reuse of the PUF-10 showed that oil removal efficiency remained greater than 95% after five consecutive cycles., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Polyurethane dish-washing (PU-DW) sponges are functionalized sequentially with polyethylenimine (PEI) and graphene oxide (GO) to form PEI/reduced graphene oxide (RGO) PU-DW sponges. The PEI/RGO PU-DW sponge consists of PEI/RGO sheets having numerous pores, with diameters ranging from 236 to 254nm. To further enhance hydrophobicity and absorption capacity of oil, PEI/RGO PU-DW sponge is further coated with 20% phenyltrimethoxysilane (PTMOS). The PTMOS/PEI/RGO PU-DW sponge absorbs various oils within 20s, with maximum absorption capacity values of 880% and 840% for bicycle chain oil and motorcycle engine oil, respectively. The absorbed oils were released completely by squeezing or immersed in hexane. The PTMOS/PEI/RGO PU-DW sponge efficiently separates oil/water mixtures through a flowing system. Having the advantages of faster absorption rate, reusability, and low cost, the PTMOS/PEI/RGO PU-DW sponge holds great potential as a superabsorbent for efficient removal and recovery of oil spills as well as for the separation of oil/water mixtures., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Solvents screening experiments using a Soxhelt extractor were conducted to determine the best solvents for oil removal from spent bleaching clay. The solvents extracted oil in the following decreasing amount: methylethylketone > benzene-ethanol mixture (1:1 by volume) > acetone > trichloroethylene = dichloromethane > chloroform > petroleum ether > benzene > n-hexane > methanol. Four of the safest solvents, methylethylketone, acetone, petroleum ether and n-Hexane were selected for further studies. Large scale treatment of spent clay with the selected solvents were conducted in a batch stirred reactor. The effect of solvent type, solvent to clay ratio (SCR), time of extraction and extent of mixing on the percentage of oil extracted (POE) were investigated. The corresponding optimum conditions for the four solvents were: extraction time time = S minutes, solvent to clay ratio = 4 to 5, extraction temperature = 25 deg. C (room temperature) and mixing rate = 150 to 200 RPM. The bleaching efficiency (compaerd to to fresh clay) of the clay deoiled by methylethylketone, acetone, petroleum ether and n-hexane were 77%, 65%, S 1 % and 27%, respectively. [ABSTRACT FROM AUTHOR]

More than 425 million used oil filters (UOFs) are discarded annuallyin the United States. These filters contain an estimated 67500 m3 (17.8 million gallons) of used oil that could leach from landfills and pollute soil and water. The Environmental Protection Agency (EPA) has mandated that non terne-plated used oil filters which have been gravity hot drained for at least 12 h are considered non-hazardous and acceptable for landfilling. Filters must be either puncturedin the dome end, punctured in the anti-siphon valve, or crushed before draining to meet the requirements for this EPA exemption. This paper evaluates the factors which affect the removal of used oil from UOFs by gravity hot-draining and crushing. The factors studied include oil temperature and viscosity, dome-end puncturing, draining orientation, filter design, time, and crushing force. Of these factors, oil temperature, puncturing of the dome end, filter orientation, and filter design were found to have a significant impact on oil removal by gravity draining. Orientation is very important because an oil filter drained to EPA's recommendations still contains a significant quantityof oil which has a high probability of draining because of normal changes in the orientation of a filter during transport or placement ina landfill. During crushing, oil temperature, filter design, and crushing force were found to significantly impact oil removal. [ABSTRACT FROM AUTHOR]

The influence of different nutrients on biosurfactant production by Rhodococcus erythropolis was investigated. Increasing the concentration of phosphate buffer from 30 up through 150 mmol/L stimulated an increase in biosurfactant production, which reached a maximum concentration of 285 mg/L in shaken flasks. Statistical analysis showed that glycerol, NaNO3, MgSO4 and yeast extract had significant effects on production. The results were confirmed in a batchwise bioreactor, and semi-growth-associated production was detected. Reduction in the surface tension, which indicates the presence of biosurfactant, reached a value of 38 mN/m at the end of 35 hours. Use of the produced biosurfactant for washing crude oil-contaminated soil showed that 2 and 4 times the critical micellar concentration (CMC) were able to remove 97 and 99% of the oil, respectively, after 1 month of impregnation.