This study examines the merits of esterification of waste cooking oil to reduce its acidic content for use as a rejuvenator for aged asphalt. It further examines how acidic compounds in bitumen increases the moisture susceptibility of bituminous composites made from siliceous stones and bitumen. While some acidic compounds are inherent in bitumen, the recent widespread use of bio-modifiers such as waste cooking (vegetable) oil has further increased the acidic compounds in bio-modified bitumen. Acidic compounds adsorb well to siliceous stones, but they are easily replaced by water molecules, giving rise to moisture damage. It was found that a reduction or removal of the acidic compounds of waste cooking oil via transesterification significantly enhances its resistance to moisture damage. The study results showed that treated waste cooking oil is not only a promising rejuvenator to be used with aged bitumen, but also quite resistant to moisture damage. It was also found that transesterification reduces the acid value of bitumen from 12 to 0.27 (mg KOH/g). This turned a moisture-susceptible bitumen to nearly a moisture-resistant bitumen as evidenced by nearly no change in moisture-induced shear thinning after 24hr water conditioning. The outcome of the study shows significant role of acidic compounds in moisture damage, and the importance of accounting for the acidity of rejuvenators to ensure their durability. The study results confirm the feasibility of tuning waste cooking oil to a sustainable asphalt rejuvenator to promote both resource conservation and asphalt recycling.

这项研究探讨了将废食用油酯化以降低其酸性含量以用作老化沥青再生剂的优点。它进一步研究了沥青中的酸性化合物如何增加由硅质石和沥青制成的沥青复合材料的水分敏感性。尽管某些酸性化合物是沥青中固有的，但近来广泛使用的生物改性剂，例如废烹饪油（植物油），进一步增加了生物改性沥青中的酸性化合物。酸性化合物可以很好地吸附到硅质石头上，但是很容易被水分子取代，从而导致水分受损。已经发现，通过酯交换反应减少或除去废食用油中的酸性化合物，显着增强了其对水分破坏的抵抗力。研究结果表明，经过处理的废食用油不仅是一种可与老化的沥青一起使用的有希望的复兴剂，而且还具有很好的抗潮害能力。还发现酯交换将沥青的酸值从12降低到0.27（mg KOH / g）。24小时的水调节后，水分诱导的剪切稀化几乎没有变化，这证明了对水分敏感的沥青几乎变成了防潮沥青。研究结果表明，酸性化合物在湿气损害中具有重要作用，并且考虑到再生剂的酸度以确保其耐用性非常重要。研究结果证实了将废弃的食用油调配成可持续的沥青再生剂以促进资源节约和沥青回收的可行性。