01991nas a2200229 4500008004100000022001400041245009600055210006900151260009000220300001000310490000600320520113200326100001601458700003101474700001901505700002901524700002301553700002101576700002201597700001801619856012401637 2016 eng d a2045-232200aBiosurfactant as a promoter of methane hydrate formation: thermodynamic and kinetic studies0 aBiosurfactant as a promoter of methane hydrate formation thermod aMACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLANDbNATURE PUBLISHING GROUPcFEB a208930 v63 a

Natural gas hydrates (NGHs) are solid non-stoichiometric compounds often regarded as a next generation energy source. Successful commercialization of NGH is curtailed by lack of efficient and safe technology for generation, dissociation, storage and transportation. The present work studied the influence of environment compatible biosurfactant on gas hydrate formation. Biosurfactant was produced by Pseudomonas aeruginosa strain A11 and was characterized as rhamnolipids. Purified rhamnolipids reduced the surface tension of water from 72 mN/m to 36 mN/m with Critical Micelle Concentration (CMC) of 70 mg/l. Use of 1000 ppm rhamnolipids solution in C type silica gel bed system increased methane hydrate formation rate by 42.97% and reduced the induction time of hydrate formation by 22.63% as compared to water saturated C type silica gel. Presence of rhamnolipids also shifted methane hydrate formation temperature to higher values relative to the system without biosurfactant. Results from thermodynamic and kinetic studies suggest that rhamnolipids can be applied as environment friendly methane hydrate promoter.

1 aArora, Amit1 aCameotra, Swaranjit, Singh1 aKumar, Rajnish1 aBalomajumder, Chandrajit1 aSingh, Anil, Kumar1 aSanthakumari, B.1 aKumar, Pushpendra1 aLaik, Sukumar uhttps://library.ncl.res.in/content/biosurfactant-promoter-methane-hydrate-formation-thermodynamic-and-kinetic-studies-102325nas a2200289 4500008004100000020004100041245008300082210006900165260012400234520125600358653001901614653002001633653003001653653002701683653001601710100001601726700003101742700001901773700002301792700002201815700002901837700001801866700001301884700001501897700001401912856010901926 2016 eng d a978-81-322-2773-1; 978-81-322-2771-700aRole of Rhamnolipid: A biosurfactant in methane gas hydrate formation kinetics0 aRole of Rhamnolipid A biosurfactant in methane gas hydrate forma a7th Floor, Vijaya Building, 17, Barakhamba Rd, New Delhi, 110 001, IndiabSardar Swaran Singh Natl Inst Bio-EnergycFEB3 a

Naturally occurring methane gas hydrate is a vast source of methane gas which is trapped in crystalline ice-like structure present in permafrost regions and under the sea in outer continental margins. It is purposed that total amount of carbon in the form of methane hydrates is almost twice the carbon content in all the fossil fuel reserves put together, and hence these are supposed to be the future potential energy resource. This paper investigates the laboratory investigations on effect of a biosurfactant rhamnolipid on methane hydrate formation kinetics. Rhamnolipid was produced by Pseudomonas aeruginosa strain A11. The presence of P. aeruginosa has been reported in Gulf of Mexico gas hydrate samples. Biosurfactant reduced the surface tension of water from 72 to 36 mN/m with CMC of 70 mg/L. The biosurfactant dose is studied at two different concentrations in the solution at 100 and 1000 ppm. Kinetic of hydrate formation and growth is compared at 0, 100, and 1000 ppm of rhamnolipid showing that rhamnolipid acts as a hydrate promoter at these concentrations. Thus, small dosages of rhamnolipids produced by P. aeruginosa strain A11 must clearly affect the gas hydrate formation kinetics in natural sites (as in Gulf of Mexico).

10aInduction time10amethane hydrate10aPotential energy resource10aPseudomonas aeruginosa10aRhamnolipid1 aArora, Amit1 aCameotra, Swaranjit, Singh1 aKumar, Rajnish1 aSingh, Anil, Kumar1 aKumar, Pushpendra1 aBalomajumder, Chandrajit1 aLaik, Sukumar1 aKumar, S1 aKhanal, SK1 aYadav, YK uhttps://library.ncl.res.in/content/role-rhamnolipid-biosurfactant-methane-gas-hydrate-formation-kinetics02364nas a2200289 4500008004100000022001400041245012000055210006900175260000800244300000600252490000700258520141400265653001801679653001101697653001601708653001901724653002101743100001601764700003101780700002901811700001901840700002301859700002101882700002201903700001801925856013101943 2021 eng d a0025-323500aRhamonolipids produced by Pseudomonas aeruginosa promotes methane hydrates formation in fixed bed silica gel medium0 aRhamonolipids produced by Pseudomonas aeruginosa promotes methan cMAR a50 v423 a

Natural gas hydrates are seen as an alternative future energy source. They have also been valued for their carbon dioxide capturing capability, gas separation, desalination, natural gas storage and transportation. Developing economical and viable gas hydrate based technology is one of the most promising research areas of present decade. Successful commercialization of gas hydrate based technology is often curtailed due to slow formation rate. The present study evaluates biosurfactant as a kinetic promoter of methane hydrates formation in a fixed bed C type silica gel medium. Biosurfactant was produced by growing Pseudomonas aeruginosa strain A11 in glycerol supplemented mineral salt medium. Biosurfactant characterization with FTIR, NMR and MALDI-TOF spectroscopy reveled it to be a glycolipids type biosurfactant namely rhamnolipids. Saturating C type silica gel with of 100 ppm rhamnolipids solution enhanced the rate of methane hydrates formation by reducing the induction time. Mole of methane consumed and percentage of water to hydrate conversion was observed to be more in 1000 ppm rhamnolipids saturated C type silica gel as compared to quiescent water system and water saturated silica gel system. Overall results suggest that rhamonolipids produced by strain A11 in combination with silica gel can be utilized as environmentally safe kinetic promoter for methane hydrate formation.

10aBiosurfactant10aEnergy10aGlycolipids10aInduction time10aKinetic promoter1 aArora, Amit1 aCameotra, Swaranjit, Singh1 aBalomajumder, Chandrajit1 aKumar, Rajnish1 aSingh, Anil, Kumar1 aSanthakumari, B.1 aKumar, Pushpendra1 aLaik, Sukumar uhttps://library.ncl.res.in/content/rhamonolipids-produced-pseudomonas-aeruginosa-promotes-methane-hydrates-formation-fixed-bed