Influence of Surfactant on the Morphology of Copper Oxide Prepared from Acidic Etching Waste Solutions

In order to study the effects of four surfactants， dodecyl dimethylamine ethylene lactone (BS-12)， sodium dodecyl sulfate (SDS)，cetyl pyridinium bromide (CPDB) and Tween-80， as well as their addition sequence and calcination temperature， on the morphology and particle size of copper oxide (CuO) prepared from acid etching waste solution.The microstructure of CuO was characterized using X-ray diffractometer (XRD) and infrared spectrometer (FT-IR).The micro-topography of copper oxide was examined with scanning electron microscope(SEM).The particle size distribution and thermal stability of CuO were investigated through particle size analysis and thermogravimetric (TG)testing.Molecular dynamics calculations were conducted using the Forcite module in MS software under the COMPASS force field to study the energy changes during the adsorption process of surfactant molecules on the CuO surface.Results showed that after the addition of surfactants，CuO particles exhibited uniform distribution and consistent size.The four optimal surfactants were identified as BS-12， SDS， CPDB and Tween-80.The order in which the surfactants were added did not affect the composition or morphology of the CuO product.The CuO samples prepared with BS-12 added first had a smaller average particle size compared to those with BS-12 added later， with sizes of 2.85 nm and 7.50 nm， respectively.When calcined at 400 ℃， CuO particles prepared with BS-12， SDS， CPDB and Tween-80 all exhibited irregular sheet-like structures with increased average particle sizes of 25，27，40 and 55 nm，respectively.After simulated motion，all four surfactants spontaneously adsorbed onto the CuO surface， with temperature and energy stabilizing rapidly after brief fluctuations， indicating the relative stability of the adsorption model systems.The adsorption energies of BS-12， SDS， CPDB and Tween-80 on the CuO surface were -762.73， -556.10，-619.47 and -739.81 kcal/mol， respectively， with the adsorption strength ranked as BS-12＞Tween-80＞CPDB＞SDS.The addition of surfactants in the preparation of CuO from acidic etching waste liquids effectively improved the uniformity of CuO particles.