粗甘油生產丙烯酸之不同合成路徑分析：嚴格製程設計、技術經濟、及生命週期評估

Abstract

本研究旨在提出並評估兩種利用來自生質廢棄物粗甘油作為原料的丙烯酸（AA）生產流程。方案1使用丙烯醛作為中間體，而方案2則使用丙烯醇作為中間體。根據流程中可獲得的不同層級資訊，系統性地優化了這兩個流程（方案1以三個目標進行優化，方案2以單一目標進行優化）。在技術經濟評估方面，方案2的最低所需銷售價格（MRSP）為每公斤2.122美元，略優於方案1的每公斤2.537美元。這兩個數值都明顯高於以丙烯為原料的傳統製程的市場價格（每公斤1.24至1.32美元）。隨後，進行了從搖籃到大門的生命週期評估，並在五個影響類別（即全球暖化潛力、化石資源稀缺性、人體非致癌毒性、用水量和陸地酸化）中對這些流程進行比較。我們觀察到，如果能解決丙烯醛在廢水中殘留的問題，方案1可以比方案2和傳統製程更具可持續性。相反，方案2即使與傳統製程相比也遠不環保，主要原因是使用甲酸作為共反應物。

This study aims to propose and evaluate two acrylic acid (AA) production processes that utilize bio-based crude glycerol as a feedstock. Scheme 1 employs acrolein as an intermediate, while Scheme 2 utilizes allyl alcohol as an intermediate. Both processes were systematically optimized based on varying levels of information available in the process (i.e. three objectives for Scheme 1, single objective for Scheme 2). From a techno-economic evaluation, Scheme 2 (2.122 USD/kg) slightly outperforms Scheme 1 (2.537 USD/kg) in terms of the minimum required selling price (MRSP). Both values are significantly higher than the market price (1.24 to 1.32 USD/kg) based on the conventional process that uses propene as a feedstock. Subsequently, a cradle-to-gate life cycle assessment was conducted to compare these processes across five impact categories (i.e., global warming potential, fossil source scarcity, human non-carcinogenic toxicity, water consumption, and terrestrial acidification). We have observed that Scheme 1 can be more sustainable than Scheme 2 and the conventional process if the issue associated with the acrolein left in the wastewater can be addressed. In contrast, Scheme 2 is far from environmentally friendly even compared to the conventional process, primarily because of the use of formic acid as a co-reactant.