Journal of Cleaner Production ( IF 11.1 ) Pub Date : 2020-10-19 , DOI: 10.1016/j.jclepro.2020.124477 Rômulo Pereira de Almeida , Rayane Cristine Gomes Aciole , Antonia Infantes-Molina , Enrique Rodríguez-Castellón , Jose Geraldo Andrade Pacheco , Ivoneide de Carvalho Lopes Barros
The production of biodiesel from acidic non-edible oil and waste lipid feedstocks has the drawback of forming soaps in the conventional transesterification process. A solution is the esterification reaction that uses superacid homogenous catalysts; however, it generates dangerous effluents. To overcome this, heterogeneous acid catalysts such as heteropolyacid supported on activated carbon have been studied for the production of biofuel. Due to its high surface area, the activated carbon allows high dispersion of the active phase. The aim of this work was to study the esterification of oleic acid over 12-tungstophosphoric acid (HPW) supported on activated carbon derived from passion fruit biomass (ACP), prepared by chemical activation using ZnCl2. The composites (HPW/ACP) were prepared containing 10-30 wt% of HPW by following two procedures: aqueous impregnation method and incipient moisture. The results showed that the activated carbon prepared from the residue of the passion fruit seed presented a high surface area (465 m2. g-1) and that the HPW impregnation method on activated carbon was a decisive factor on the catalyst performance. XPS, SEM, NMR and N2 adsorption-desorption results showed that in the catalyst obtained by aqueous impregnation (HPW/ACP) surface area decreased (50 m2.g-1), HPW was highly dispersed in the internal pores of the ACP support and presented superior acidity. The incipient moisture impregnation (HPW/IACP) formed HPW particles on the external surface of the support with little interaction among them, resulting in surface area of 90 m2.g-1. The best result of oleic acid esterification with methanol led to 86.4% conversion with catalyst HPW30/ACP, at 100 °C, after 2h of reaction. The leaching of HPW active phase after the reaction was low ∼ 1.0 - 2.6%. This study showed the importance of the HPW impregnation method on activated carbon to obtain a more stable and more active catalyst for the production of biodiesel. A detailed analysis of the catalyst synthesis from a fruit industry residue demonstrated the possibility of operating in a closed-loop system towards cleaner production.
中文翻译:
百香果种子中残留的活性炭作为H 3 PW 12 O 40的载体,用于油酸的酯化
由酸性不可食用油和废脂质原料生产生物柴油的缺点在于,在常规的酯交换过程中会形成肥皂。解决方案是使用超酸均相催化剂的酯化反应。但是,它会产生危险的废水。为了克服这个问题,已经研究了负载在活性炭上的非均相酸催化剂,例如杂多酸,用于生产生物燃料。由于其高表面积,活性炭可以使活性相高度分散。这项工作的目的是研究油菜籽对百香果生物质(ACP)衍生的活性炭上负载的12-钨磷酸(HPW)的酯化作用,该活性炭是使用ZnCl 2化学活化制备的。通过以下两个步骤制备包含10-30重量%的HPW的复合物(HPW / ACP):水性浸渍法和初期水分。结果表明,从西番莲果种子的残基制得的活性碳呈现高的表面积(465米2。克-1)和在活性炭上的HPW浸渍法是对催化剂性能的决定性因素。XPS,SEM,NMR和N 2吸附-解吸结果表明,在水浸渍(HPW / ACP)制得的催化剂中,表面积减少(50 m 2 .g -1)。),HPW高度分散在ACP载体的内部孔中,并具有卓越的酸性。初始水分浸渍(HPW / IACP)在载体的外表面形成HPW颗粒,它们之间几乎没有相互作用,导致表面积为90 m 2 .g -1。反应2h后,在100°C时,用甲醇进行油酸酯化的最佳结果导致催化剂HPW30 / ACP的转化率为86.4%。反应后HPW活性相的浸出低至约1.0-2.6%。这项研究表明,在活性炭上进行HPW浸渍方法对于获得更稳定,活性更高的生物柴油生产催化剂非常重要。对水果行业残留物合成催化剂的详细分析表明,有可能在闭环系统中进行清洁生产。