Microbial chain elongation enables the conversion of organic wastes and agroindustrial sidestreams into medium chain carboxylic acids (MCCAs), with application in the production of plasticizers, personal care products, functional feed additives, and fuels. This work describes the up-scaling of the production of MCCAs from thin stillage, and their separation into an oil at kilogram scale with a MCCA content of more than 72%. The chain elongation occurred at a maximum rate of 1.7±0.6 g MCCA L^-1 d^-1 without the use of ethanol as electron donor, even when it was supplied. Two in-line extraction trains are compared: (1) solvent extraction based on pertraction followed by electrochemical phase separation of the acids through a 2-compartment membrane electrolysis (ME) cell, and (2) direct electrochemical extraction from the fermentation broth using a 3-compartment ME cell. Using the first treatment train, n-caproic acid was extracted at an efficiency of 73%. The decrease in the fermentation pH from 5.5 to 5.0 enabled doubling the MCCA and oil production rate without a concomitant increase in NaOH dosage for pH stabilization. The selectivity brought about by pertraction and its capacity to up-concentrate MCCAs in an alkaline-pH extract enabled a more efficient use of the electricity for ME (as low as 6.2 kWh kg^-1 oil) when compared to a period when ME was applied directly to the filtered fermentation broth (160 kWh kg^-1 oil). The 3-compartment ME cell was able to phase separate oil extracting directly from the fermentation broth but it was not selective for longer-chain carboxylic acids due to co-extraction of short chain carboxylic acids and inorganic anions.

微生物链的延长能够将有机废物和农用工业的支流转化为中链羧酸（MCCA），并应用于增塑剂，个人护理产品，功能性饲料添加剂和燃料的生产中。这项工作描述了由稀釜馏物生产MCCA的规模扩大，以及将它们分离成公斤级的MCCA含量超过72％的油。链延长的最大速率为1.7±0.6 g MCCA L ^-1 d ^-1即使使用乙醇也不使用乙醇作为电子供体。比较了两种在线提取方法：（1）基于萃取的溶剂提取，然后通过2室膜电解（ME）电池对酸进行电化学相分离，以及（2）使用3隔室ME电池。使用第一个治疗序列n己酸的萃取效率为73％。发酵pH从5.5降低到5.0可使MCCA和产油率提高一倍，而不会同时增加用于稳定pH的NaOH剂量。与应用ME的时期相比，通过萃取所产生的选择性及其在碱性pH提取物中高浓度MCCA的能力使ME的电力使用效率更高（低至6.2 kWh kg ^-1油）。直接进入过滤后的发酵液（160 kWh kg ^-1油）。3室ME池能够直接从发酵液中分离出油，但由于短链羧酸和无机阴离子的共萃取，因此对长链羧酸没有选择性。