02224nas a2200193   4500008004100000022001400041245013000055210006900185260007100254300001400325490000700339520143400346100002401780700002301804700002701827700002201854700002601876856012801902       2012                        eng d  a0888-588500aPreparation of pure methyl esters from corresponding alkali metal salts of carboxylic acids using carbon dioxide and methanol0 aPreparation of pure methyl esters from corresponding alkali meta  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcFEB  a1498-15050 v513 a<p>In the present article, for the first time, we report the synthesis of alkyl esters by direct esterification of alkali metal salts of carboxylic acids using carbon dioxide and alcohol. Methyl acetate, methyl benzoate, methyl salicylate, and methyl lactate have been synthesized by esterification of sodium acetate, sodium benzoate, sodium salicylate, and calcium lactate, respectively. The esterification reaction was carried out in a batch as well as in a semicontinuous mode of operation. A detailed study on the esterification of calcium lactate using methanol and carbon dioxide was carried out to record the effects of various operating parameters (like CO2 pressure, reaction temperature, moisture content in the calcium lactate, and initial concentrations of calcium lactate) on the esterification reaction. This synthesis route produces highly pure methyl lactate by direct esterification of calcium lactate with calcium carbonate as byproduct. The byproduct calcium carbonate was characterized for its crystallinity, surface area, and pore volume. The process route has the advantage that the synthesized byproduct can be recycled into the fermenter to make corresponding alkali metal lactate or the finely precipitated calcium carbonate can be used for various other applications. Thus, the recovery and recycle of alkali metal is possible providing a pollution free process for synthesis of pure methyl lactate.</p>1 aBarve, Prashant, P.1 aKamble, Sanjay, P.1 aJoshi, Jyeshtharaj, B.1 aGupte, Milind, Y.1 aKulkarni, Bhaskar, D.  uhttps://library.ncl.res.in/content/preparation-pure-methyl-esters-corresponding-alkali-metal-salts-carboxylic-acids-using-002370nas a2200193   4500008004100000022001400041245022700055210006900282260007100351300001400422490000700436520149300443100002301936700002401959700002701983700001802010700002602028856012202054       2012                        eng d  a0888-588500aPurification of lactic acid via esterification of lactic acid using a packed column, followed by hydrolysis of methyl lactate using three continuously stirred tank reactors (CSTRs) in series: a continuous pilot plant study0 aPurification of lactic acid via esterification of lactic acid us  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcFEB  a1506-15140 v513 a<p>The world market of lactic acid is growing every year, mainly as a solvent and precursor to poly(lactic acid) (PLA). The cost of renewable biomass-derived PLA will have to compete with other synthetic polymers, if it is to grab a significant and sustainable fraction of the market share. It is thus necessary to have efficient and cost-effective technology for the production of pure-grade lactic acid (LA). In this article, a novel cost-effective, eco-friendly continuous process for the production of high-quality lactic acid at pilot plant scale has been demonstrated. The novelty of this process is that, for the first time, we report and use the concept of inverse reactive distillation for the esterification of crude concentrated LA in a continuous countercurrent packed column mode. This allows us to operate the column at higher temperatures, improving the kinetic rate process and leading to shorter columns. This is followed by the hydrolysis of methyl lactate (MLA) in a series of three continuously stirred tank reactors (CSTRs), where LA itself acts as a catalyst. The LA obtained in the pilot plant process shows 99.81% purity (by weight) on water-free basis and has an optical purity of 99.9%. The pilot scale experimental results pertaining to the autocatalytic esterification of LA and hydrolysis of MLA have been compared and validated, with respect to simulated results. The innovations reported here can make the process economically viable for commercial use.</p>1 aKamble, Sanjay, P.1 aBarve, Prashant, P.1 aJoshi, Jyeshtharaj, B.1 aRahman, Imran1 aKulkarni, Bhaskar, D.  uhttps://library.ncl.res.in/content/purification-lactic-acid-esterification-lactic-acid-using-packed-column-followed-0