NOVELTY - Process (P1) for preparing sterile meropenem trihydrate, comprises: (a) dissolving meropenem or its hydrate in water in the presence of an alcoholic base and in the presence or absence of solvent; (b) optionally filtering through micron filter; (c) adjusting the pH to 4.5-6.5; and (d) optionally washing with solvent to yield sterile meropenem trihydrate.    USE - The process is useful for preparing sterile meropenem trihydrate (claimed), which is used as an antibiotic to treat pneumonia, urinary tract infections, intra-abdominal, gynecological, skin and soft tissue infections, meningitis, septicemia and febrile neutropenia. No biological data given.    ADVANTAGE - The process: utilizes carbonated water for the isolation of diprotected meropenem in step (b1) which reduces effluent treatment load significantly and avoids the presence of phosphate salt to give better quality of the product; utilizes methanolic ammonia that facilitates dissolution at lower temperatures, and minimizes degradation of meropenem; and avoids the use of anti-solvent or seeding for the precipitation of the sterile meropenem, thus providing the sterile meropenem trihydrate with high yield and purity, in an economical and environmentally friendly manner.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a process (P2) for preparing sterile meropenem trihydrate, comprising: (a1) reacting 1-azabicyclo(3.2.0)hepta-2-ene-2-carboxylic acid, 3-((diphenoxyphosphinyl)oxy)-6-(1-hydroxyethyl)-4-methyl-7-oxo-(4-nitrobenzyl)methyl ester,(4R-(4a,5b,6b(Rasterisk))) with (2S,4S)-2-(dimethylaminocarbonyl)-4-mercapto-1-(p-nitrobenzyloxycarbonyl)-1-pyrrolidine in a solvent and a base to yield diprotected meropenem (which is (R)-3-((3S,5S)-5-dimethylcarbamoyl-1-(4-nitro-benzyloxycarbonyl)-pyrrolidin-3-ylsulfanyl)-6-((R)-1-hydroxy-ethyl)-4-methyl-7-oxo-1-aza-bicyclo(3.2.0)hept-2-ene-2-carboxylic acid 4-nitro-benzyl ester); (b1) isolating the diprotected meropenem by quenching in carbonated water; (c1) deprotecting the diprotected meropenem in a solvent and a buffer in water, followed by hydrogenation to obtain non-sterile meropenem trihydrate; and (d1) optionally converting non-sterile meropenem trihydrate into sterile meropenem trihydrate by using a solvent and alcoholic ammonia solution in presence of carbon dioxide.