Newsletter June 2022

Research updates

Project 1.

The Electrochemical Advanced Oxidation Processes (EAOPs) team have made some progress in the treatment of metal plating wastewater with particular attention given to degradation of Ni-EDTA complexes and recovery of Ni. A pilot-scale EAOP reactor has been fabricated using innovative electrodes designed by CTET. The CTET-designed pilot-scale system can successfully remove 80% EDTA and recover 80% Ni from the Ni-EDTA wastewater at a treatment capacity of 0.9 tonnes/day.

Project 2.

The Membrane Capacitive De-ionization (MCDI) team have fabricated a 100-pair electrode module which successfully reduced the conductivity in synthetic groundwater by 60-70% with a water recovery of 86% in a 50-cycle test. The treated groundwater can meet the conductivity recommended in the Australian drinking water guidelines.

China Learning Centre

UNSW Sydney launched its first China Learning Centre (CLC) in T3 2020 at the Yixing Industrial Park for Environmental Science and Technology (ES&TP), where UNSW Centre for Transformational Environmental Technologies (CTET) is located, to support those students who cannot return to the campus in Sydney to continue their studies. From T3 2020 to T1 2022, the Yixing CLC has assisted more than 420 students to take online courses, develop thesis projects and carry out industrial training.

While borders are now open, the Yixing CLC is continuing to operate with activities such as an online workshop held on 1^st June to assist students to utilize the resources of the UNSW library. Additionally, the CLC is continuing to assist students in finding industrial training placements and to provide a place for undergraduate and postgraduate students to mix with their peers in both a convenient study environment and friendly social setting.

External communication

Prof. David Waite, the Executive Chairman of CTET and Dr Yuan Wang, the General Manager of CTET met multiple industrial and governmental partners in Beijing, Nanjing as well as Yixing to explore future cooperation opportunities during their recent 10-week visit to China.

• Beijing Originwater Technology Co., Ltd. (27th April, Beijing): discussed potential areas of future cooperation with the BOW Chairman Dr Jianping Wen and key members of his executive and research team.
• China Coal Technology & Engineering Group (28th April and 6th May, Beijing): exchanged opinions with the executive and research teams in relation to technology development, academician workstation setup and joint supervision of PhD students. David delivered a keynote talk at the "Science and Technology Hall".
• Jiangsu Environmental Protection Group Co., Ltd. and Jiangsu Environmental Engineering &Technology Co., Ltd (8th May and 13th May, Nanjing): discussed the industrialization of advanced oxidation technologies as well as the development of advance oxidation equipment. David delivered a talk in the Open Class (25th issue) of Jiangsu Environmental Protection Group.
• Jiangsu Industrial and Research Institute (JITRI) and Yangtze River Delta National Technology Innovation Centre (12th May, Nanjing): David provided a keynote lecture as the first speaker in "International Academician Lecture (12th issue)" in which he described his experience of the challenges related to translation of research from bench scale studies to full scale application. JITRI Director Qing Liu indicated that he was keen to seek close cooperation between CTET and JITRI in the near future.
• Yixing Environmental Protection Science &Technology Industrial Park (ES&TP, 17th and 24th May, Yixing): met Director Yunxia Zhang from Yixing Science and Technology Bureau and other leaders from ES&TP and discussed the development of the Yixing environmental protection industry, talent programmes as well as the future strategy of CTET. David, invited by Secretary Chunxiao Feng, provided a keynote speech at the Innovation and Development Symposium of Yixing Energy Conservation and Environmental Protection Enterprises.
• Visit to CTET by Yixing governmental group (20th, 23rd and 24th May, Yixing): Director Qijun Tang from the Yixing Science and Technology Bureau, Vice-Mayor Hongbiao Chu, and Director Changqing Li from the Ministry of Industry and Information Technology together with their team visited CTET. They appreciated the contribution that CTET has made to the development of the environment industry in Yixing and indicated that they will continue to fully support CTET to achieve new academic and economic milestones. Vice-Mayor Hongbiao Chu indicated that he is keen to strengthen the cooperation between UNSW as well as other Australian universities and ES&TP.
• The Board of Directors of CTET (24th May, Yixing): The CTET Board reviewed progress to date and discussed plans for renewal of the joint venture agreement between UNSW and ES&TP. There was unanimous support for continuation of CTET with agreement reached on the nature of the future arrangement between UNSW and ES&TP. Proposals for development of pilot scale testing facilities and an MCDI electrode pilot manufacturing line were strongly supported.

Publications

1. CTET recently published a research paper entitled “Comparative Experimental and Computational Studies of Hydroxyl and Sulfate-radical Mediated Degradation of Simple and Complex Organic Substrates” in Environmental Science and Technology. The paper builds on the outcome of a cooperating project between CTET and Beijing Originwater Technology Co., Ltd, which is aimed at treating nanofiltration concentrates from a municipal wastewater treatment plant. Through a systematic comparison between the hydroxyl and sulfate-radical mediated advanced oxidation processes, this work articulates the strengths and weaknesses of the two processes for application to wastewater treatment. Results of the study suggest that the sulfate-radical mediated process is not suitable for treatment of wastewaters containing high concentrations of organic contaminants and halide ions in view of the long -time scales required for oxidation of the organic contaminants, the excessive increase in concentration of SO₄²⁻ in the treated wastewater and the possible formation of chlorinated by-products.

2. Another research paper entitled “Hydroxyl Radical Production via Reaction of Electrochemically Generated Hydrogen Peroxide and Atomic Hydrogen: An Effective Process for Contaminant Oxidation?” has been published in Environmental Science and Technology by CTET. This paper describes investigations of a so-called “green” Fenton technology which requires input of water, air and electricity only. A palladium-coated carbon-PTFE gas diffusion electrode (Pd/C GDE) was used as a catalytic cathode with hydroxyl radical (^•OH) formed as a result of the reaction of electrogenerated hydrogen atoms (H^*) with in situ generated hydrogen peroxide (H₂O₂). The studies show that H^* and H₂O₂ (and thus ^•OH) can be electrogenerated effectively over a wide range of pH (3.2–9.0). These results suggest that by in situ generation of H^* and H₂O₂, the H^*/GDE process is able to produce significant amounts of ^•OH without external chemical addition though further research is needed to increase the durability of the electrodes used.