01468nas a2200145   4500008004100000022001400041245008000055210006900135260007100204300001400275490000700289520089600296100002301192856010701215       2007                        eng d  a0888-588500aMass transfer in bubble column reactors: effect of bubble size distribution0 aMass transfer in bubble column reactors effect of bubble size di  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcMAR  a2205-22110 v463 a<p>Mass transfer in a bubble column is analyzed in a different perspective. The experiments were performed in a bubble column reactor that was operated in a regime where the overall rate of absorption of gas into liquid was dependent on both the mass-transfer coefficient and the rate of reaction. Homogeneous catalytic oxidation of sodium sulfite was considered as a model reaction. The local instantaneous velocity data was measured using LDA in the presence of reaction and was used to yield the bubble size distribution at several locations in the column. The role of individual bubble size during mass transfer with chemical reaction was observed to vary. The findings suggest that a narrow bubble size distribution would help to achieve uniformity in the performance at bubble scale, so that an identical regime of mass transfer with reaction exists at the individual bubble level.</p>1 aKulkarni, Amol, A.  uhttp://library.ncl.res.in/content/mass-transfer-bubble-column-reactors-effect-bubble-size-distribution01289nas a2200145   4500008004100000245007900041210006900120260000800189300001200197490000700209520078200216100002200998700002301020856010001043       2016                        eng d00aMixing of medium viscosity liquids in a stirred tank with fractal impeller0 aMixing of medium viscosity liquids in a stirred tank with fracta  cNOV  a914-9210 v503 aMixing of viscous liquids in a stirred tank is a daunting task. The present paper explores the possibility of using a fractal impeller for mixing of viscous liquids in a stirred tank. The analysis includes power consumptions characteristics, mixing characteristics and the flow patterns in the stirred tank. Ultrasonic velocity profiler (UVP) was used to measure the local velocities in the stirred tank. Fractal impeller found to exhibit different power consumption characteristics than known for conventional impellers. For the range of viscosities 0.58-0.192 Pa s, mixing time found to be directly proportional to the power consumption per unit mass. The normalised mean radial velocity profiles were found to be independent of fluid viscosities studied in the present work.1 aMule, Gunwant, M.1 aKulkarni, Amol, A.  uhttp://library.ncl.res.in/content/mixing-medium-viscosity-liquids-stirred-tank-fractal-impeller01312nas a2200169   4500008004100000022001400041245015600055210006900211260000800280300001600288490000700304520062800311100002000939700002300959700003100982856012901013       2017                        eng d  a1528-748300aMicrowave assisted batch and continuous flow synthesis of palladium supported on magnetic nickel nanocrystals and their evaluation as reusable catalyst0 aMicrowave assisted batch and continuous flow synthesis of pallad  cAUG  a5163–51690 v173 aPalladium nanocrystals (NCs) supported on nickel NCs (Pd/Ni) were synthesized in a continuous flow manner by the microwave-assisted method in the presence and absence of oleylamine. Parameters optimized for batch experiments were considered while performing continuous flow synthesis. The Pd/Ni NCs synthesized in the presence of oleylamine displayed good catalytic activity for hydrogenation of aromatic nitro compounds, and those bearing alkene, and alkyne moieties. The ferromagnetic character of the supporting nickel NCs allowed the recovery of the catalyst and these recovered catalysts could be reused several times.1 aNikam, Arun, V.1 aKulkarni, Amol, A.1 aPrasad, Bhagavatula, L. V.  uhttp://library.ncl.res.in/content/microwave-assisted-batch-and-continuous-flow-synthesis-palladium-supported-magnetic-nickel01448nas a2200181   4500008004100000022001400041245008300055210006900138260000800207300001200215490000600227520083400233100001801067700002701085700002101112700002301133856011001156       2018                        eng d  a2058-988300aMulti-step continuous flow synthesis of the cystic fibrosis medicine ivacaftor0 aMultistep continuous flow synthesis of the cystic fibrosis medic  cAUG  a520-5260 v33 a<p>A continuous flow ozonolysis method combined with a multi-step flow sequence is developed for the synthesis of the drug ivacaftor for the first time. Safe ozonolysis, a continuous flow quadruple reaction to construct a quinolone scaffold, and inline extraction followed by continuous phase separation are the key features of the present work. The feasibility of using a continuous mixed flow reactor, commonly referred to as a continuous stirred tank reactor (CSTR), is also investigated for the relatively slow reaction step. The current integrated multi-step flow synthesis can produce 7.2 g of the drug ivacaftor per day on a laboratory scale, which is sufficient to treat 50 patients per day. The present route can also be used as a general route for the synthesis of other related drugs such as quinolone antibiotics.</p>1 aVasudevan, N.1 aSharma, Mrityunjay, K.1 aReddy, Srinivasa1 aKulkarni, Amol, A.  uhttp://library.ncl.res.in/content/multi-step-continuous-flow-synthesis-cystic-fibrosis-medicine-ivacaftor01604nas a2200241   4500008004100000022001400041245010400055210006900159260000900228300001600237490000700253520076200260653002001022653003201042653001601074653002401090653002701114100002201141700002601163700002401189700002301213856012601236       2021                        eng d  a0947-653900aMulti-step synthesis of miltefosine: integration of flow chemistry with continuous mechanochemistry0 aMultistep synthesis of miltefosine integration of flow chemistry  cDEC   a17695-176990 v273 aHerein we report for the first time, an advanced continuous flow synthesis of the blockbuster Leishmaniasis drug miltefosine from simple starting materials by a sequence involving four steps of chemical transformation including a continuous mechanochemical step. First three reaction steps were performed in simple tubular reactors in a telescopic mode, while in the last step the product precipitated from the 3(rd) step was used for a continuous mechanochemical synthesis of miltefosine. When compared to a typical batch protocol that takes 15 h, miltefosine was obtained in 58 % overall yield in flow synthesis mode at the laboratory scale in a total residence time 34 min at synthesis rate of 10 g/hr, which is sufficient to treat 4800 patients per day.10acontinuous flow10acontinuous mechanochemistry10amiltefosine10amultistep synthesis10areactive intermediates1 aPatil, Niteen, B.1 aAtapalkar, Ranjit, S.1 aChavan, Subhash, P.1 aKulkarni, Amol, A.  uhttp://library.ncl.res.in/content/multi-step-synthesis-miltefosine-integration-flow-chemistry-continuous-mechanochemistry