Evaluation of effects of selected wax inhibitors on wax appearance and disappearance temperatures

[[abstract]]©2003 Taylor & Francis - In this investigation, a light transmittance method was used to evaluate the wax appearance temperatures (WAT) and wax disappearance temperatures (WDT) of model paraffin compounds (n-C24H50 (C-24) and n-C36H74 (C-36)) in n-decane (C-10) solutions both with and without wax inhibitors. The change in WAT at different paraffin. concentrations in the presence of an inhibitor behaves as though there is a constant amount of paraffin removed by the inhibitor. However; the amount of apparent paraffin reduction by an inhibitor (e.g. 160 g of C-24 by one gram of an inhibitors indicates that the inhibition mechanism cannot easily be explained by a simple "sequestering" effect. Wax inhibitors that decrease the WAT tend to also increase the WDT. Most of the wax inhibitors tested at a dosage of 100 ppm did suppress the WAT of lower molecular weight paraffin (C-24) solutions, but had little or no effect for higher molecular weight paraffin (C-36) solutions. Side-chain length of polymethacrylate wax inhibitors is an important performance parameter. Of the three polymethacrylate wax inhibitors tested, the one with the longest alkyl side-chain (C-18) had the most effect on suppressing the WAT and increasing the WDT of the binary mixtures n-C-10-n-C-24 solutions).[[department]]生醫工程與環境科學