Electrolyzed water as a green cleaner: chemical and physical characterization at different electrolysing parameters

Abstract

The aims of this study were to develop electrolysed technique and evaluate the characteristics and performance of electrolysed water that will be applied as a cleaning medium in the food industry. Acidic electrolyzed water (AcEW) and neutral electrolyzed water (NEW) have been reported to have a strong bactericidal effect on various types of foodborne pathogens for many types of food products and food equipment surfaces. While alkaline electrolyzed water (AlEW) is a potential cleaning medium for alkaline wash. The shelf life of electrolyzed water generated from the lab-scale electrolyzing unit was investigated to obtain the best quality electrolyzed water for a long duration. The electrolyzed water was stored in closed dark-brown glass bottles at room temperature. Effect of electrolyzing parameters (electrode type, NaCl concentration, electrical voltage and electrolysis time) on chemical and physical properties (pH, oxidation-reduction potential (ORP), total chlorine, free chlorine, dissolved oxygen) of electrolyzed water (alkaline, acidic, and neutral electrolyzed water) were studied. The chemical and physical properties of electrolyzed water were measured after 24 hrs. Results showed that as time increased, the chemical and physical properties of electrolyzed decreased and eventually reduced the electrolyzed water quality. Freshly prepared electrolyzed water is suggested for cleaning application in food industry. The usage of electrolyzed water is expected to help the food industry in achieving a hygienic environment in their factory and at the same time minimizing the cleaning cost.

Optimization of Electrolysis Parameters for Green Sanitation Chemicals Production Using Response Surface Methodology

“…Current efficiency is, according to Faraday's law, the ratio of the actual mass of a substance liberated from an electrolyte by the current's passage to the theoretical mass liberated [12]. Equations ( 1) to (3) were used to calculate the theoretical total chlorine [12]. The mass of chlorine produced from the electrolysis experiments was calculated using Equation (4).…”

“…Hsu et al [36] concluded that the electrical conductivity of an electrode is mainly responsible for the production of chlorine. However, studies conducted by Khalid et al [12] revealed that a titanium-silver pairing with higher electrical conductivity (σ of silver = 6.3 × 10 7 S/m) produced a lower chlorine content compared with a titanium-stainless steel pairing (σ of stainless steel= 1.45 × 10 6 S/m) (0.17 and 0.5 mg Cl 2 /L, respectively). The quantity of chlorine generated is significantly low in the study conducted by Khalid et al [12] as the lab-scale electrolyzing unit has a low current efficiency.…”

“…However, studies conducted by Khalid et al [12] revealed that a titanium-silver pairing with higher electrical conductivity (σ of silver = 6.3 × 10 7 S/m) produced a lower chlorine content compared with a titanium-stainless steel pairing (σ of stainless steel= 1.45 × 10 6 S/m) (0.17 and 0.5 mg Cl 2 /L, respectively). The quantity of chlorine generated is significantly low in the study conducted by Khalid et al [12] as the lab-scale electrolyzing unit has a low current efficiency. According to Natarajan [41], higher exchange current density on electrodes will increase the hydrogen gas production.…”

“…Their budget allocation for sanitation and wastewater treatment are often at a minimum due to financial barriers. EW is reported to be inexpensive, uses on-site generation, and does not require a considerable amount of detergent storage space [1,4,12]. Moreover, in contact with organic matter or when diluted by tap water, osmosis water, and distilled water, acidic electrolyzed water (AcEW) will revert to its original form [1,4,13,14].…”

“…Several works in the literature have reported the effect of different electrolyzing parameters, which are the electrode types [36][37][38][39], electrode electrical conductivity [12,40], electrode's exchange current density [12,41], NaCl concentration [42,43], salt type [14], flow rate [42,43], temperature [42,43], electrical potentials [36,37], and electrolysis time [37] on the physical and chemical properties of AcEW. In contrast, studies on the usage of AlEW are still not well defined in the literature.…”