Sudirjo Emilius, Buisman Cees J N, Strik David P B T B
Government of Landak Regency, West Kalimantan, Indonesia.
Environmental Technology, Wageningen University & Research, Wageningen, Netherlands.
Front Microbiol. 2019 May 14;10:934. doi: 10.3389/fmicb.2019.00934. eCollection 2019.
Marine sediment has a great potential to generate electricity with a bioelectrochemical system (BES) like the microbial fuel cell (MFC). In this study, we investigated the potential of marine sediment and activated carbon (AC) to generate and store electricity. Both internal and external energy supply was validated for storage behavior. Four types of anode electrode compositions were investigated. Two types were mixtures of different volumes of AC and Dutch Eastern Scheldt marine sediment (67% AC and 33% AC) and the others two were 100% AC or 100% marine sediment based. Each composition was duplicated. Operating these BES's under MFC mode with solely marine sediment as the anode electron donor resulted in the creation of a bio-battery. The recharge time of such bio-battery does depend on the fuel content and its usage. The results show that by usage of marine sediment and AC electricity was generated and stored. The 100% AC and the 67% AC mixed with marine sediment electrode were over long term potentiostatic controlled at -100 mV vs. Ag/AgCl which resulted in a cathodic current and an applied voltage. After switching back to the MFC operation mode at 1000 Ω external load, the electrode turned into an anode and electricity was generated. This supports the hypothesis that external supply electrical energy was recovered via bi-directional electron transfer. With open cell voltage experiments these AC marine bioanodes showed internal supplied electric charge storage up to 100 mC at short self-charging times (10 and 60 s) and up to 2.4°C (3,666 C/m anode) at long charging time (1 h). Using a hypothetical cell voltage of 0.2 V, this value represents an internal electrical storage density of 0.3 mWh/kg AC marine anode. Furthermore it was remarkable that the BES with 100% marine sediment based electrode also acted like a capacitor similar to the charge storage behaviors of the AC based bioanodes with a maximum volumetric storage of 1,373 C/m anode. These insights give opportunities to apply such BES systems as e.g., bio-battery to store and use electricity for off-grid purpose in remote areas.
海洋沉积物具有通过生物电化学系统（BES）（如微生物燃料电池（MFC））发电的巨大潜力。在本研究中，我们研究了海洋沉积物和活性炭（AC）发电及储能的潜力。验证了内部和外部能量供应的储能行为。研究了四种类型的阳极电极组成。两种是不同体积的AC与荷兰东斯海尔德河口海洋沉积物的混合物（67%AC和33%AC），另外两种是基于100%AC或100%海洋沉积物的。每种组成都进行了重复实验。以纯海洋沉积物作为阳极电子供体，在MFC模式下运行这些BES，形成了一个生物电池。这种生物电池的充电时间确实取决于燃料含量及其使用情况。结果表明，通过使用海洋沉积物和AC可以发电并储能。100%AC以及67%AC与海洋沉积物混合的电极在相对于Ag/AgCl为-100 mV的长期恒电位控制下，产生了阴极电流和外加电压。在1000Ω外部负载下切换回MFC运行模式后，电极转变为阳极并产生电力。这支持了通过双向电子转移回收外部供应电能的假设。通过开路电压实验，这些AC海洋生物阳极在短自充电时间（10秒和60秒）内显示内部供应电荷存储高达100 mC，在长充电时间（1小时）内高达2.4°C（3,666 C/m阳极）。使用假设的电池电压0.2 V，该值代表0.3 mWh/kg AC海洋阳极的内部储能密度。此外，值得注意的是，基于100%海洋沉积物的电极的BES也表现得像一个电容器，类似于基于AC的生物阳极的电荷存储行为，最大体积存储为1,373 C/m阳极。这些见解为将此类BES系统应用于例如生物电池以在偏远地区存储和使用电力用于离网目的提供了机会。
