This paper reports a set of experimental data of clathrate-hydrate formation from HFC-32 (difluoromethane) gas in contact with an aqueous solution of sodium dodecyl sulfate (SIDS). This supersedes the corresponding data that we previously reported in this journal [Watanabe et al., 2005. Surfactant effects on hydrate formation in an unstirred gas/liquid system: an experimental study using HFC-32 and sodium dodecyl sulfate. Chemical Engineering Science 60, 4846-4857] with the new data reported herein, because of a suspicion of hydrate plugging occurring in the gas-feed line of our experimental system used to obtain the previous data. The new data show much higher levels in both the hydrate formation rate and the final water-to-hydrate conversion ratio as compared to the previous data. Neither the hydrate formation rate nor the water-to-hydrate conversion ratio exhibited a significant change with the SDS concentration in the aqueous phase over the range from 1000 to 4000 ppm. (c) 2007 Elsevier Ltd. All rights reserved.