Used waste cooking oil (WCO) or frying oils are being considered as rich sources of economical feedstock for biodiesel production. To carry out the process of trans-esterification of WCO to methyl esters (biodiesel), zeolite/chitosan/KOH composite was used as solid heterogeneous catalysts. The composite was analyzed using Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscope coupled with Energy Dispersive X-ray (SEM-EDX) analysis, and X-ray diffraction (XRD) analysis. It was found that the treatment of the natural zeolite (clinoptilolite zeolite) with KOH significantly decreased its silica content by desilication and increased its K+ content by formation of hydroxylpotaslite. Electrolysis method (EM) is used as an applicable technology for recovery of energy and resources during waste treatment. Theoretically, EM can convert any biodegradable waste into H-2, O-2, biofuels, as well as other by-products such as glycerol. However, the system efficacy can vary significantly under different circumstances. The conversion of biodiesel from WCO was obtained for 1 wt.% catalyst concentration and alcohol/oil ratio of 1:7 at 40 V in the presence of water as 2 wt.% of the whole solution in 3 h, produced 93% yield. The optimum conversion process was achieved as a result of using co-solvent as acetone. Fourier Transform Infrared (FT-IR) and Viscosity characterization were used the assessing techniques for detection of WCO and biodiesel. (C) 2017 Elsevier Ltd. All rights reserved.