Method for constructing electro-catalytic bacterial biofilm at anode of microbial electrochemical reactor

Abstract

The invention relates to a method for constructing an electro-catalytic bacterial biofilm at an anode of a microbial electrochemical reactor. The method comprises the following steps: firstly assembling the microbial electrochemical reactor and connecting with circuits, wherein the first path is formed by connecting a fixed resistor between the anode and a cathode in series, and the second path is formed by connecting a direct current stabilized power supply, an ampere meter, a variable resistor and a working contact of a cycle time relay between the anode and the cathode in series; then injecting a bacterial growth culture medium liquid into an anode chamber, inoculating a bacteria source, conducting the first path to carry out prestart on the microbial anode, measuring the anode potential change to obtain a polarization curve and determining an ultimate current value of the anode; and after electro-catalytic bacterial biofilm is stimulated by using ultimate pulse current to grow, successively obtaining a new ultimate current value again, then stimulating again under the new ultimate pulse current, repeating the steps till no significant growth of the ultimate current exists and finishing construction of the anodic electro-catalytic bacterial biofilm. The electro-catalytic bacterial biofilm can stably run under relatively high working current.

Description

technical field [0001] The invention relates to a method for constructing an electrocatalyzed bacterial biofilm on the anode of a microbial electrochemical reactor, and belongs to the technical field of microbial electrochemical reactors. Background technique [0002] Microbial electrochemical reactors include microbial fuel cells, microbial electrolysis cells, and microbial electrochemical sensors. In microbial electrochemical reactors, the electrocatalytic activity and operational stability of the electrocatalytic bacterial biofilm attached to the electrode surface are the key components that determine the performance of the reactor. A stable and efficient electrocatalytic bacterial biofilm can improve the performance of microbial fuel cells and microorganisms. Energy efficiency of electrolytic cells, increased sensitivity of microbial electrochemical sensor signal responses. Electrocatalytic bacterial biofilm is a cell accumulation layer with a certain spatial structure ...

AI Technical Summary

Problems solved by technology

[0006] The electrocatalytic bacterial biofilm constructed by the potential adaptation method generally has the following shortcomings: (1) the limit working current that the electrode can reach is small, and the electrocatalytic efficiency is low; Poor endurance, when the working current passing through the electrode approaches or exceeds its limit current, the electrode will be rapidly over-polarized, and over-polarization will cause the anode potential to move positively to +1.2V in a short period of time (usually no more than 10 minutes) (compared to the standard hydrogen electrode), such a high anode potential will cause irreversible damage to the bacteria themselves, resulting in the destruction of the electrocatalytic bacterial biofilm and the loss of catalytic function

In short, the electrocatalytic bacterial biofilm constructed by the potential adaptation method generally has the disadvantages of low catalytic activity and poor adaptability to high working current. Unable to work continuously and stably at an operating current close to its limiting current level

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