Consumer behavior towards new energy vehicles: Developing a theoretical framework.

New energy vehicles (NEVs), owing to their low carbon emission, have gained immense importance to achieve the net-zero emission target. The global NEVs market has grown significantly over the last decade. China, the United States (US), and Europe are the leading markets for NEVs. This study systematically and critically reviews NEV literature on consumer behavior pertaining to NEV adoption. An attempt is made to uncover the current research trends, research settings, theoretical perspectives, and key factors influencing consumer behavior towards NEVs. These factors are further categorized into five broad factors: (a) economic factors, (b) policy and regulatory factors, (c) psychological factors, (d) infrastructural and technological factors, and (e) demographic factors. Through a critical analysis of existing theories, this study delineates the complex phenomenon of consumer behavior towards NEV adoption, offering a holistic understanding of the key factors influencing consumer behavior. This review suggests that purchasing price, charging infrastructures, consumers' attitudes towards the environment, and government policies are decisive to NEV adoption. This study contributes to the NEV adoption literature by proposing an integrated theoretical framework. Further, it outlines the managerial and policy implications for transitioning towards NEVs to achieve net-zero emission targets.

Development and calibration of a new mathematical model for the description of an ion-exchange process for ammonia removal in the presence of competing ions.

Ammonia ion removal and recovery via an ion-exchange process using zeolites is a promising alternative to traditional biological treatments. The analysis of its efficiency is not straightforward as it depends on various factors, such as the cation exchange capacity of the zeolite, amount of zeolite available, initial ammonia concentration, contact time, ammonia speciation depending on pH or the presence of competing ions. Mathematical modelling and simulation tools are very useful to analyse the effect of different operational conditions on the efficiency and optimal operation of the process. This paper experimentally analyses the effect that the presence of competing ions has on the efficiency of ammonia removal. This experimental work has shown a reduction of around 21% of ammonia removal efficiency in the presence of competing ions. The main contribution of this paper is the development new mathematical model able to describe the ion-exchange process in the presence of competing ions. The mathematical model developed is able to analyse the performance of the IEX process under different empty bed contact times, influent loads, pH and concentrations of competing ions. The capability of the model to reproduce real data has been proven comparing the experimental and simulation results. Finally, an exploration by simulation has been undertaken to show the potential of the mathematical model developed.

Resilience and life cycle assessment of ion exchange process for ammonium removal from municipal wastewater.

This study was completed to understand the resilience of an ion exchange (IEX) process for its ability to remove variable ammonium (NH4+-N) loads) and to prove its environmental benefits through a life cycle assessment (LCA). The tertiary 10 m3/day demonstration scale IEX was fed with variable NH4+-N concentrations (<0.006-26 mg NH4+-N /L) naturally found in municipal wastewater. Zeolite-N was used as ion exchange media and regeneration was completed with 10% potassium chloride (KCl). The influent NH4+-N concentration impacted the ion exchange capacity, which ranged from 0.9-17.7 mg NH4+-N/g media. When the influent concentration was <2.5 mg NH4+-N/L, the Zeolite-N released NH4+-N (up to 12%). However, the exchange increased up to 62% when the influent NH4+-N load peaked, confirming the resilience of the process. A 94% regeneration efficiency was obtained with fresh regenerant, however, with the increase of the mass of NH4+-N on the media, the regeneration efficiency decreased. An optimisation of the volume of brine and regeneration contact time is suggested. To further measure the benefits of the IEX process, an LCA was conducted, for a 10,000 population equivalent reference scenario, and compared with traditional nitrification-denitrification WWTP. The LCA revealed that IEX with regenerant re-use and NH4+-N recovery through a membrane stripping process resulted in reductions of: 25% cumulative energy demand; 66% global warming potential and 62% marine eutrophication potential, when compared to traditional WWTP. This work demonstrated that the IEX process is an efficient and an environmentally benign technology that can be widely applied in WWTPs.