02617nas a2200133 4500008004100000245009500041210006900136260000800205520208600213100002302299700002802322700002202350856011102372 2019 eng d00a Exploring the steady operation of a continuous pilot plant for the di-nitration reaction 0 aExploring the steady operation of a continuous pilot plant for t cAUG3 a

Continuous-flow synthesis of the selective herbicide pendimethalin was demonstrated in both a laboratory-scale and a pilot-scale reactor using only concentrated nitric acid as nitrating agent. The di-nitration reaction follows second-order kinetics where the reaction is first order with respect to both reactant and nitric acid. The pinched-tube reactor was chosen for pilot-scale reactor fabrication due to its excellent mixing and mass transfer characteristics compared to a straight-tube reactor. The estimated mass transfer coefficient showed similar nature in the laboratory-scale and the pilot-scale pinched-tube reactor, ensuring similar performance at the pilot scale. Di-nitration in continuous flow, inline quenching, extraction, and phase separation are some of the salient features of the developed pilot plant. The importance of the start-up time for achieving steady state in the flow system at the large scale is highlighted.
 

1 aSharma, Mrityunjay1 aAcharya, Roopashree, B.1 aKulkarni, Amol, A uhttps://library.ncl.res.in/content/exploring-steady-operation-continuous-pilot-plant-di-nitration-reaction01728nas a2200277 4500008004100000022001400041245009200055210006900147260000800216300001200224490000700236520085900243653002001102653001401122653001701136653000801153653001301161100002001174700002301194700001801217700002801235700001701263700002601280700002301306856012101329 2021 eng d a2062-249X00aDesign and scale-up of continuous di-nitration reaction using pinched tube flow reactor0 aDesign and scaleup of continuous dinitration reaction using pinc cSEP a611-6240 v113 aScale-up of the di-nitration reaction for synthesis of selective herbicide pendimethalin using only nitric acid in continuous flow is presented in this work. This work showcases an approach for smooth scale-up for an herbicide for a production capacity of 50 kg/day using a pinched tube reactor. The approach begins with the batch experiments followed by flow synthesis using a 1/8-inchSS316 helical coil tube where kinetics of the di-nitration was determined, and process optimization was done. Systematic approach was followed for quantification of heat transfer, mass transfer and residence time distribution and scale-up. Detailed scale-up methodology is presented with effect of relevant parameters for successful scale-up. Modular pilot plant with inline quenching, extraction and separation are some of the salient features presented in this work.10acontinuous flow10anitration10aPinched tube10aRTD10ascale-up1 aHussain, Arshad1 aSharma, Mrityunjay1 aPatil, Suneha1 aAcharya, Roopashree, B.1 aKute, Mahesh1 aWaghchaure, Aishwarya1 aKulkarni, Amol, A. uhttps://library.ncl.res.in/content/design-and-scale-continuous-di-nitration-reaction-using-pinched-tube-flow-reactor