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With the growing awareness of environmental protection and safe production, as well as rising costs, more and more people are asking a question: I want to use safer and more environmentally friendly methods to replace the traditional solvent (hydrocarbon) cleaners. At this point, many people will immediately reply that water-based cleaners can be used instead. But do you think choosing any water-based cleaner will solve this problem? Do you think just replacing the liquid will solve the problem? The answer is: NO. Next, we will discuss the conditions and preparations required to truly replace solvent cleaners. I. Determine whether an aqueous cleaning agent is suitable for cleaning dirt. As is well known, solvent-based cleaning agents have a strong cleaning power. Some materials are not suitable for cleaning with water-based cleaners; the cleaning principle of solvent-based cleaners is simply based on the dissolving power of the solvents. The degreasing mechanism based on the solubility of fats or oily contaminants is the principle of like dissolves like. Hydrocarbons such as gasoline and kerosene can easily dissolve heavy oil; other hydrocarbons are miscible with similar halogenated hydrocarbons (such as carbon tetrachloride and trichloroethane). This is also the reason why water is miscible with compounds that have OH groups similar to those in water, such as R-COOH (lower fatty acids) and R-OH (lower alcohols). The solubility between different liquids is closely related to surface tension and interfacial tension. For example, the surface tension of solvents such as benzene and cycloalkanes is not very different from that of tar and lubricating oils; the interfacial tension between them is low, allowing for easy mutual solubility. Regarding the solvency of solvents for fats or oily stains, at a constant temperature, the lower the temperature at which the solution cools during this process, the greater the solubility of the solute in that solvent. If what needs to be cleaned are oils, cutting fluids, or impurities, it is entirely possible to use aqueous cleaners as a substitute. II. Choosing the right aqueous cleaner Aqueous cleaners can be roughly divided into neutral cleaners and alkaline cleaners. The principle of neutral cleaning agents is to use surfactants to remove oil stains. Alkaline cleaners primarily remove oil stains through saponification. Here, I recommend neutral cleaning agents more, as they cause little harm to both humans and the workpieces. The design of such agents also places greater demands on the skills of formulators. Among the thousands of surfactants, the art of continuous combination and arrangement is beyond the reach of strong alkaline cleaners. III. When using water-based cleaners, it is necessary to follow the appropriate procedures. Many people asked me after switching to water-based cleaners why they couldn’t clean effectively Only after I found out did I realize that they were still using the original solvent cleaning process. This is actually not correct. The correct procedure for using an aqueous cleaning agent should be cleaning, rinsing, and subsequent steps. The workpiece is cleaned with a solution prepared from a cleaning agent, followed by rinsing with clean water to remove any residual mixture. Depending on the required rust prevention duration, it can be dried either by heat or air drying, and a rust inhibitor can then be applied (it is advisable to use HR-21A104 long-lasting rust inhibitor or HR-32A105 water-based rust inhibitor; using pure rust oil may not yield good results, as oil and water do not mix well). The above are the ideas for improving traditional solvent cleaning; you may find them useful for reference. One final thing to add: there are no perfect products in the world; only me and you, who keep striving for improvement.