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991.
《International Journal of Hydrogen Energy》2019,44(43):23856-23867
In this paper, the synergistic effects of advanced oxidization reactions in a combination of TiO2 photocatalysis are comparatively investigated for hydrogen production and wastewater treatment applications. An experimental study is conducted with a photoelectrochemical reactor under a UV-light source. TiO2 is selected as the photocatalyst due to the high corrosion resistant nature and ability to form hydroxyl radicals with the interaction with photons. The synergetic effects of advanced oxidization processes (AOPs) such as Fenton, Fenton-like, photocatalysis (TiO2/UV) and UV photolysis (H2O2/UV) are investigated individually and in a combination of each other. The Fenton type reagent in the reactor is formed by anodic sacrificial of stainless-steel electrode with the presence of H2O2. The influences of various parameters, including pH level, type of the electrode and electrolyte and the UV light, on the performance of the combined system are also investigated experimentally. The highest chemical oxygen demand (COD) removal efficiency is observed as 97.9% for the experimental condition which combines UV/TiO2, UV/H2O2 and photo-electro Fenton type processes. The maximum hydrogen production rate from the photoelectrolysis of wastewater is obtained as 7.0 mg/Wh for the experimental condition which has the highest rate of photo-electro Fenton type processes. The average enhancement with the presence of UV light on hydrogen production rates and COD removal efficiencies are further calculated to be 3% and 20%, respectively. 相似文献
992.
《International Journal of Hydrogen Energy》2019,44(32):17238-17247
The suitability of molasses, Napier grass (Pennisetum purpureum), empty fruit bunches (EFB), palm oil mill effluent (POME), and glycerol waste as a co-substrate with Chlorella sp. TISTR 8411 biomass for biohythane production was investigated. Mono-digestion of Chlorella biomass had hydrogen and methane yield of 23–35 and 164–177 mL gVS−1, respectively. Co-digestion of Chlorella biomass with 2–6% TS of organic wastes was optimized for biohythane production with hydrogen and methane yield of 17–75 and 214–577 mL gVS−1, respectively. The hydrogen and methane yield from co-digestion of Chlorella biomass with molasses, POME, and glycerol waste was increased by 8–100% and 80–264%, respectively. The biohythane production of co-digestion of Chlorella was 6–11 L L-mixed waste−1 with an optimal C/N ratio range of 19–41 and H2/CH4 ratio range of 0.06–0.3. Co-digestion of Chlorella biomass was significantly improved biohythane production in term of yield, production rate, and kinetics. 相似文献
993.
《International Journal of Hydrogen Energy》2021,46(57):28925-28935
The present study investigates the effect of applying voltage and current pulses during alkaline water electrolysis using 3-D Ni-based electrodes. The pulses had a square shape and alternated hydrogen production and resting time. When voltage pulses were applied, it was observed that the current at on-time was systematically higher than the current during DC electrolysis. However, during off-time, a change in polarization was observed, which decreased the overall voltage pulse performance. For pulses with a 50% duty cycle and a pulse width of 1 ms, the current response was mainly capacitive and almost no hydrogen production occurred. Current pulses on the other hand were proven to be much more promising in improving the energetic process efficiency. In that case, a pulse period of 2 ms resulted in an overpotential reduction of 17% for a 50% duty cycle. This reduction further increased to 28% when decreasing the duty cycle to 20%. Finally, in all cases where faradaic processes were dominant, applying a forced electrolyte flow was shown to be beneficial. 相似文献
994.
Khalid Almutairi Seyyed Shahabaddin Hosseini Dehshiri Seyyed Jalaladdin Hosseini Dehshiri Ali Mostafaeipour Alibek Issakhov Kuaanan Techato 《International Journal of Hydrogen Energy》2021,46(36):18795-18815
Increasing energy demand has led to a substantial growth in the use of wind energy across the world, which can be attributed to the low initial and running costs and rapid and easy deployment of this technology. The development of hydrogen from wind energy is an excellent way to store the excess wind power produced, as the produced hydrogen can be used not only as clean fuel but also as input for various industries. Considering the good wind potentials of Yazd province, the variety of industries that are active in this area, and the central location of this province in Iran, which gives it ample access to major transport routes and other industrial hubs, hydrogen production from wind power in this province could benefit not only this region but the entire country. Given these considerations, we conducted a technical, economic, and environmental assessment of the potential for wind power generation and hydrogen production in Yazd province. Overall, the assessments showed that the best locations for harvesting wind energy in this province are Bahabad and Halvan stations. For these two stations, it is recommended to use EWT DW 52-900 turbine to take advantage of its higher nominal capacity to achieve higher electricity and hydrogen output and emission reduction. For Abarkoh and Kerit stations, which have a low wind energy potential, it is recommended to use small turbines such as Eovent EVA120 H-Darrieus. Also, economic and technical assessments showed that it is not economically justified to harvest wind energy in Ardakan station. The results of ranking the stations with the Step-wise Weight Assessment Ratio Analysis (SWARA) and Evaluation based on Distance from Average Solution (EDAS) techniques showed that Bahabad station was introduced as the best place to produce hydrogen from wind energy. 相似文献
995.
Christoph Spiegel Manfred Kraut Georg Rabsch Christof Küsters Wolfgang Augustin Stephan Scholl 《化学工程与技术》2019,42(10):2067-2075
The application of highly effective microstructured devices in continuous production and industrial environments is frequently prone to fouling. A new method is presented to characterize fouling in these microstructures. Thermal fouling of aqueous solutions containing whey protein were used as a test system. Different fouling effects could be observed and distinguished. Integral fouling indicators, such as thermal fouling resistance and pressure drop, as conventional criteria for the occurrence of fouling were compared with direct local optical observation. Low thermal fouling resistances could be detected. 相似文献
996.
Lijing Yang Congmin Fan Jiapeng Zhang Fengming Zhang Ran Li Shuang Yi Yue Sun Hua Dong 《International Journal of Hydrogen Energy》2021,46(45):23236-23244
In the present work, a SiO2@PAA catalyst for NaBH4 methanolysis composed of silica nanoparticles modified with poly(acrylic acid) has been developed. The morphology and composition of the prepared SiO2@PAA catalyst were analyzed with transmission electron microscopy, Fourier transform-infrared spectroscopy, x-ray photoelectron spectroscopy and thermogravimetric analysis. This catalyst showed excellent catalytic performance for methanolysis of NaBH4. The NaBH4 methanolysis reaction catalyzed by SiO2@PAA showed an average hydrogen generation rate 5.5 times as high as the reaction catalyzed by unmodified SiO2 and 10.6 times as high as the uncatalyzed reaction, respectively. The activation energy for methanolysis of NaBH4 catalyzed by this SiO2@PAA catalyst was 24.03 kJ/mol. Moreover, although the catalytic activity of SiO2@PAA catalyst partially lost after being used, it could be restored after being regenerated by washing with diluted hydrochloric acid solution. 相似文献
997.
Yinxiang Wang Muhammad Zaki Memon Majid Ali Seelro Weng Fu Yuan Gao Yingchao Dong Guozhao Ji 《International Journal of Hydrogen Energy》2021,46(45):23358-23379
Sorption-enhanced-steam-reforming (SESR) is a thermochemical conversion technology that produces a high-purity hydrogen stream by utilizing in-situ removal of CO2 with a sorbent. In this paper, the advantages and disadvantages of CaO based sorbents, alkali-metal based sorbents (Na2ZrO3, Li2ZrO3 and Li4SiO4), hydrotalcite based sorbents, bifunctional materials and sorbents prepared from wastes are briefly discussed, and the techniques to improve the sorption properties of these CO2 sorbents are summarized. In the process of hydrogen production by sorption-enhanced-steam-reforming, the selection of suitable high-temperature CO2 sorbent is the key to produce high purity hydrogen. Furthermore, the hydrogen-production performance of the above-mentioned sorbents in the SESR process is investigated and summarized. Finally, a future perspective and some suggestions regarding these five types of sorbents are put forward. 相似文献
998.
Syed Altan Haider Muhammad Sajid Saeed Iqbal 《International Journal of Hydrogen Energy》2021,46(2):1671-1681
The focus of this study is the use of Machine Learning methods to forecast Solar Hydrogen production potential for the Islamabad region of Pakistan. For this purpose, we chose a Photovoltaic-Electrolytic (PV-E) system to forecast electricity and, hence, hydrogen production. The weather data used for forecasting and simulation were recorded with precise meteorological instruments stationed in Islamabad, over the course of 13 and a half months. Out of the three tested algorithms, Prophet performs the best with Mean Absolute Percentage Error of 3.7%, forecasting a daily average Hydrogen production of 93.3 × 103 kg/Km2. Although, the forecast in this study is made for the month of August and September, during which the local season moves towards winter, this study demonstrates solar hydrogen production, as a green energy source, has a tremendous potential in this region. 相似文献
999.
H2 production via water–gas shift (WGS) reaction in a Pd membrane reactor prepared by the electroless plating technique (ELP) “organic–inorganic” method was investigated. Pd nanoparticles embedded polyethylene glycol (PEG) was used as a polymer template during the activation step. Gas permeation results showed an infinite selectivity for H2/N2 with a H2 flux of 0.004–0.016 mol/m2·s depending on operating conditions while it decreased until 0.0005 mol/m2·s for gas mixtures. Furthermore, WGS membrane reactor experiments showed a maximum CO conversion of 98.5% with a H2 recovery of 16% at 450°C. The membrane performance was consistent during WGS catalytic membrane reactors (CMR) tests, thereby confirming the stability of the obtained membrane. 相似文献
1000.
本工艺成功解决了传统生产工艺中催化剂与丙二醇难以分离,导致丙二醇产率低、纯度低、不能连续生产的问题。生产的丙二醇的质量更好,节能、产率高,废物实现零排放,实现了连续生产。 相似文献