Hasil untuk "Chemical technology"

Z. Abdin, Ali Zafaranloo, A. Rafiee et al.

Abstract Hydrogen is known as a technically viable and benign energy vector for applications ranging from the small-scale power supply in off-grid modes to large-scale chemical energy exports. However, with hydrogen being naturally unavailable in its pure form, traditionally reliant industries such as oil refining and fertilisers have sourced it through emission-intensive gasification and reforming of fossil fuels. Although the deployment of hydrogen as an alternative energy vector has long been discussed, it has not been realised because of the lack of low-cost hydrogen generation and conversion technologies. The recent tipping point in the cost of some renewable energy technologies such as wind and photovoltaics (PV) has mobilised continuing sustained interest in renewable hydrogen through water splitting. This paper presents a critical review of the current state of the arts of hydrogen supply chain as a forwarding energy vector, comprising its resources, generation and storage technologies, demand market, and economics.

Fenglian Fu, Qi Wang

Mustafizur Rahman, A. Oni, E. Gemechu et al.

Abstract Incorporating renewables in the power grid has challenges in terms of the stability, reliability, and acceptable operation of the power system network. One possible solution is to integrate an energy storage system with the power network to manage unpredictable loads. The implementation of an energy storage system depends on the site, the source of electrical energy, and its associated costs and the environmental impacts. Moreover, an up-to-date database with cost numbers, energy use, and resulting emissions is required for decision-making purposes. This paper reviews the techno-economic and environmental assessments of mechanical, electro-chemical, chemical, and thermal to give an update on recent developments and generate a relevant database for costs and emissions. We reviewed 91 publications, 58 on techno-economic assessment and 33 on life cycle assessment. We found that, because of economies of scale, the levelized cost of energy decreases with an increase in storage duration. In addition, performance parameters such as round-trip efficiency, cycle life, and cycle length highly influence the final costs and environmental footprints of various storage technologies. However, further research is required to build a bottom-up model that can handle all the technical parameters to quantify the levelized cost of energy and environmental footprints of the storage systems simultaneously.

Youssef Habibi, L. Lucia, O. Rojas

S. Naik, V. Goud, P. Rout et al.

Guangyin Zhen, Xueqin Lu, H. Kato et al.

D. Bhatia, N. Sharma, Joginder Singh et al.

A. Fakhru’l-Razi, A. Pendashteh, L. Abdullah et al.

J. Holladay, Jianli Hu, D. King et al.

S. Renou, J. Givaudan, S. Poulain et al.

A. Peterson, F. Vogel, R. Lachance et al.

M. Himmel, S. Ding, David K. Johnson et al.

B. Bernstein, A. Meissner, E. Lander

Chemical modifications to DNA and histone proteins form a complex regulatory network that modulates chromatin structure and genome function. The epigenome refers to the complete description of these potentially heritable changes across the genome. The composition of the epigenome within a given cell is a function of genetic determinants, lineage, and environment. With the sequencing of the human genome completed, investigators now seek a comprehensive view of the epigenetic changes that determine how genetic information is made manifest across an incredibly varied background of developmental stages, tissue types, and disease states. Here we review current research efforts, with an emphasis on large-scale studies, emerging technologies, and challenges ahead.

A. Tursi

Biomass is currently the most widespread form of renewable energy and its exploitation is further increasing due to the concerns over the devastative impacts of fossil fuel consumption, i.e., climate change, global warming and their negative impacts on human health. In line with that, the present articles reviews the different sources of biomass available, along with their chemical composition and properties. Subsequently, different conversion technologies (i.e., thermo-chemical, biochemical, and physico-chemical conversions) and their corresponding products are reviewed and discussed. In the continuation, the global status of biomass vs. the other renewable energies is scrutinized. Moreover, biomass-derived energy production was analyzed from economic and environmental perspectives. Finally, the challenges faced to further expand the share of biomass-derived energy carriers in the global energy market are presented.

D. Klemm, B. Heublein, H. Fink et al.

E. Martin, De J. Valle, E. Del et al.

G. Tchobanoglous, H. Theisen, S. Vigil

C. H. Bartholomew

P. Gogate, A. Pandit

Mohammad A. Alkhadra, Xiao Su, M. Suss et al.

Agricultural development, extensive industrialization, and rapid growth of the global population have inadvertently been accompanied by environmental pollution. Water pollution is exacerbated by the decreasing ability of traditional treatment methods to comply with tightening environmental standards. This review provides a comprehensive description of the principles and applications of electrochemical methods for water purification, ion separations, and energy conversion. Electrochemical methods have attractive features such as compact size, chemical selectivity, broad applicability, and reduced generation of secondary waste. Perhaps the greatest advantage of electrochemical methods, however, is that they remove contaminants directly from the water, while other technologies extract the water from the contaminants, which enables efficient removal of trace pollutants. The review begins with an overview of conventional electrochemical methods, which drive chemical or physical transformations via Faradaic reactions at electrodes, and proceeds to a detailed examination of the two primary mechanisms by which contaminants are separated in nondestructive electrochemical processes, namely electrokinetics and electrosorption. In these sections, special attention is given to emerging methods, such as shock electrodialysis and Faradaic electrosorption. Given the importance of generating clean, renewable energy, which may sometimes be combined with water purification, the review also discusses inverse methods of electrochemical energy conversion based on reverse electrosorption, electrowetting, and electrokinetic phenomena. The review concludes with a discussion of technology comparisons, remaining challenges, and potential innovations for the field such as process intensification and technoeconomic optimization.