Carbon sequestration and utilization are currently gaining attention as they help to reduce the emission of greenhouse gases in the atmosphere. This study explores the possibility of using carbon dioxide as a feedstock for the production of ammonium carbamate, a precursor molecule for urea production. Waste cooking oil was used as the indispensable nonaqueous medium for the formation of pure ammonium carbamate. This makes the process completely ecofriendly and cost‐effective. A continuous process of ammonium carbamate production at 20°C results in 88.86% consumption of carbon dioxide. The highest yield of ammonium carbamate was achieved at an NH₃/CO₂ ratio of 2.5. A three‐stage setup was also found to increase the yield of ammonium carbamate. The reusability of oil after each cycle was checked and it was found that the formation of the product is comparatively less compared to the previous cycle. Lower yield was observed when the same experiment was carried out with fresh oil (sunflower oil). The exit gas from the process was found to be rich in ammonia that can be further used for the production of struvite, a phosphate fertilizer. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd.

中文翻译：

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废食用油是从二氧化碳生产尿素前体氨基甲酸铵的有效溶剂

碳封存和利用目前正受到关注，因为它们有助于减少大气中的温室气体排放。这项研究探索了使用二氧化碳作为原料生产氨基甲酸铵（生产尿素的前体分子）的可能性。废食用油用作形成纯氨基甲酸铵必不可少的非水介质。这使该过程完全环保且具有成本效益。在20°C下连续生产氨基甲酸铵的过程将导致88.86％的二氧化碳消耗。在NH ₃ / CO ₂下获得最高的氨基甲酸铵收率比为2.5。还发现了三阶段设置可以增加氨基甲酸铵的收率。检查每个循环后油的可重复使用性，发现与前一个循环相比，产品的形成相对较少。当使用新鲜油（葵花籽油）进行相同的实验时，观察到较低的收率。发现该过程的出口气体富含氨，可进一步用于生产鸟粪石（一种磷肥）。©2020年化学工业协会和John Wiley＆Sons，Ltd.