Catalysis Science & Technology
·
2019
·Vol. 10
·期 5
·1431-1443
·
IF 5.726
Zhaohui Teng,Shan Huang,Liang Fu,Heng Xu,Na Li,Qulan Zhou
In our research, rice husk ash (RHA) was employed as a catalyst support and Fe–Cu bimetallic compounds were employed as catalysts in the reduction of NO by CO. Rice husk ash contains abundant amorphous SiO2 and it would be a good catalyst support as indicated by the characterization results. Different combustion conditions were tested to obtain the appropriate rice husk ash. Characterization methods were employed to study its physical properties. The results of the catalytic activity testing experiment were highly in accordance with the characterization results. Fe2Cu1 based on rice husk ash had approximately 100% conversion rates for both NO and CO, which indicated the superiority of the rice husk ash and Fe–Cu oxides. Moreover, the O2 content, CO/NO ratio and SO2 had little influence on this new combination. This remarkable performance was due to the strong interaction between the rice husk ash and metal species. The results of our research will provide some instructions for the improvement of industrial denitrification.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
Gels
·
2025
·Vol. 11
·期 1
·74
·
IF 5.3
Yun Deng,Ziyan Sha,Xingxing Wang,Ke Duan,Weijie Xue,Ian Beadham,Xiaolan Xiao,Changbo Zhang
To expand the applications of hydrophobic silica aerogels derived from rice husk ash (HSA) through simple traditional methods (without adding special materials or processes), this paper employs machine learning to establish mathematical models to identify optimal conditions for extracting water glass and investigates how preparation conditions and heat treatment temperatures affect properties such as the porosity and hydrophobicity of HSA. The results indicate that the decision tree regression model provides the most accurate predictions for the extraction rate and modulus of water glass. Notably, the water contact angle of HSA produced using nitric acid as a catalyst can reach as high as 159.5°, classifying it as a superhydrophobic material. Additionally, while moderately increasing the concentration of the hydrophobic modifier enhances HSA’s hydrophobicity, it concurrently reduces its porosity. The HSA maintained hydrophobicity until 500 °C. The pore structure of HSA collapsed gradually with the increase in heat temperature. After treatment at 700 °C, HSA lost its hydrophobicity and the porous structure was severely damaged. Compared with silica aerogel using traditional silicon sources, the damage to pore structure and the crystallization occurred at lower temperatures, but the hydrophobicity remained at higher temperatures.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
·
2015
·
IF 1.97
Shu-Ting Liu,Kang-kang Yan,Yuan hu Zhang,Shi-di Jin,Ying Ye,Xue-Gang Chen
The increase in electromagnetic pollution due to the extensive exploitation of electromagnetic (EM) waves in modern technology creates correspondingly urgent need for developing effective EM wave absorbers. In this study, we carried out the magnesiothermic reduced the rice husk ash under different temperatures (400–800 °C) and investigated the electromagnetic wave adsorption of the products. The EM absorbing for all samples are mainly depend on the dielectric loss , which is ascribed to the carbon and silicon carbide content. RA samples (raw rice husk ashed in air and was magesiothermic reduced in different temperatures) exhibit poor dielectric properties , whereas RN samples (raw rice husk ashed in nitrogen and was magesiothermic reduced in different temperatures) with higher content of carbon and silicon carbide display considerable higher dielectric loss values and broader bandwidth for RL<−5 dB and −10 dB. For RN samples, the maximum bandwidth for −5 dB and −10 dB decrease with carbon contents, while the optimum thickness decrease with increasing SiC content. The optimum thickness of RN400–800 for EM absorption is 1.5–2.0 mm, with maximum RL of between −28.9 and −68.4 dB, bandwidth of 6.7–13 GHz for RL<−5 dB and 3.2–6.2 GHz for RL<−10 dB. The magnesiothermic reduction will enhance the potential application of rice husk ash in EM wave absorption and the samples benefited from low bulk density and low thickness. With the advantages of light-weight, high EM wave absorption, low cost, RN400–800 could be promising candidates for light-weight EM wave absorption materials over many conventional EM wave absorbers.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2016
·
IF 2.74
Yajun Chen,Fenghe Wang,Lunchao Duan,Hao Yang,Jay Gao
As an agricultural waste, rice husk ash (RHA) has the potential to be a viable alternative adsorbent for the removal of tetracycline (TC) from aqueous solution. This study aims to explore its feasibility of RHA as a new adsorbent, and understand its adsorption mechanism for TC. Also assessed in this study are the influences of initial concentration of TC, adsorption time, solution pH and temperature on RHA adsorption performance. It is found that TC removal efficiency of RHA is related to the initial concentration of TC solution. TC concentration decreases sharply within the first 60 min in its adsorption process, and then only gradually, reaching the equilibrium within 600 min. RHA adsorption capacity is related to solution pH, temperature, and ion intensity, especially at a high pH value. A rise of 313 K in temperature caused the adsorption capacity to more than double. Furthermore, low-acid and high-alkaline solution can accelerate the adsorption of TC onto RHA. The highest adsorption capacity of 8.37 mg/g achieved in this study is much higher than other adsorbates reported in the literature, indicating the feasibility of RHA as a new adsorbent. The Langmuir isotherm model is the most reasonable in depicting the adsorption behavior . The pseudo second order model fits the experimental data nicely, suggesting a mostly physical and chemical control over the adsorption. Such findings can serve as a useful guide in expanding the applicability of RHA to new areas.
研究领域:
环境科学
·
农业科学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale Research Letters
·
2016
·Vol. 11
·期 1
·1-8
·
IF 2.584
Zhang Zhiliang,He Wenxiu,Zheng Jianzhong,Wang Guangquan,Ji Jianbing
Nanofluids, colloidal suspensions consisting of base fluids and nanoparticles, are a new generation of engineering working fluids. Nanofluids have shown great potential in heat/mass transfer applications. However, their practical applications are limited by the high production cost and low stability. In this study, a low-cost agricultural waste, rice husk ash (RHA), was used as a silicon source to the synthesis of silica nanofluids. First, silica nanoparticles with an average size of 47 nm were synthesized. Next, by dispersing the silica nanoparticles in water with ultrasonic vibration, silica nanofluids were formed. The results indicated that the dispersibility and stability of nanofluids were highly dependent on sonication time and power, dispersant types and concentrations, as well as pH; an optimal experiment condition could result in the highest stability of silica nanofluid. After 7 days storage, the nanofluid showed no sedimentation, unchanged particle size, and zeta potential. The results of this study demonstrated that there is a great potential for the use of RHA as a low-cost renewable resource for the production of stable silica nanofluids.
Rice husk ash was used as a low-cost renewable resource for production of silica nanofluids with high stability.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Desalination and Water Treatment
·
2016
·
IF 1.272
Kang-Kang Yan,Jiao Huang,Xue-Gang Chen,Shu-Ting Liu,Ao-Bo Zhang,Ying Ye,Mei Li,Xiaosheng Ji
Rice husk ash (RHA) is a promising low-cost adsorbent. Meanwhile, the magnetic and catalytic capabilities of ferrite nanoparticles make it efficient for water purification. In this study, we prepared RHA and rice husk/CoFe2O4 composite (RHC) and studied their methylene blue (MB) adsorption capacities in fixed-bed columns. The column regeneration was also investigated. Both RHA and RHC are amorphous materials with Brunauer, Emmet and Teller (BET) surface area of >180 m2 g−1 and mesopore volume of >0.1 cm3 g−1. The CoFe2O4 nanoparticles are mainly located on the inner surface of RHC, which significantly increased the mesopore volume and average pore size but decreased the BET surface area and micropore volume. The adsorption ability of RHC was investigated in a fixed-bed column, with RHA as control. The effects of column parameters including bed height, flow rate, and inlet MB concentration on breakthrough curves were studied. The mathematical models, such as bed-depth service time (BDST), Thomas, and Yoon–Nelson models were applied to predict the breakthrough curves. It was found that BDST model fitted the breakthrough curves best. Results showed that the breakthrough time of RHC is more than two times than that of RHA, which may be attributed to the catalytic performance of CoFe2O4 nanoparticles. The exhausted RHA and RHC were retreated by three methods and eluted of the column with ethanol caused the highest regeneration efficiency. In addition, fixed-bed tests of RHA and RHC on real dye wastewater demonstrated that these adsorbents have good practical value and application prospect.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Silicon
·
2025
·
IF 3.3
Cui Meng-Jie,Muhammad Imran,Ren Tie-Zhen,Okitsu Kenji,Fan Wei,Zhang Xue-Jun
Rice husk ash (RHA), obtained through pyrolysis of rice husk (RH), is primarily composed of silicon dioxide (SiO 2 ). However, a conventional thermal treatment produces harmful byproducts, that can pollute the environment and harm biological health. Meanwhile, energy consumption hinders scaling up a conventional producing technique. Here, an electron-assisted thermal decomposition (EATD) technology was developed to obtain silicon dioxide (SiO 2 ), which included two mixed crystal phases: cristobalite and tridymite. The influence of temperature on the SiO 2 structure was examined through the various structural characterizations. Based on the experimental findings, we emphasized that the EATD process induced specific structural phase and glass transition owning to the radiated heat system. Notably, the prepared samples displayed the ability as a chemical sensor for Cr 6+ and photocatalyst for methylene blue (MB) degradation. This unique characteristic improved the detection signal for Cr 6+ by at least twofold, resulting in a streamlined detection technique that reduced the risk of secondary pollution.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Clean Technologies and Environmental Policy
·
2024
·
IF 4.2
Wang Xingxing,Du Kaifa,Jia Yi,Zhao Wenxia,Duan Ke,Wang Xiaoyu,Beadham Ian,Hu Jie,Zhang Changbo,Deng Yun
Using rice husk ash as silicon source to prepare silica aerogels is one of the most possible ways to realize high value utilization of husk ash. However, the applications of rice husk ash-based silica aerogels (HSAs) using the conventional procedure (without incorporating special materials or processes) are limited due to their relatively inferior properties compared to silica aerogel prepared from conventional silicon sources. Therefore, it is necessary to explore new application areas where HSA can be competent. In this study, HSAs were prepared using a simple conventional protocol and utilized as fillers to enhance the corrosion resistance of epoxy coating. The results showed that the optimal HSA had a specific surface area of 470.3 m 2 /g and a water contact angle of 158.5°. The HSA/epoxy composite can be prepared simply using a magnetic stiran. When the addition amount is 6%, the coating has the best corrosion resistance. The protection efficiency remaining at 91.4%, after 20 days of immersion in a 3.5% NaCl solution, which was 48.7% for pure epoxy coating. The polarization resistance value was 7591.7% higher compared to pure epoxy coating. This performance was better than that reported for some conventional fillers in the literature. Besides the similar effect as other fillers, it is possible that the HSA may have trapped O 2 and Cl − , preventing them from contacting directly with the metal. Graphical abstract
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER COMPOSITES
·
2025
·
IF 4.7
Shengwang Yuan,Yihao Hou,Miao He,Lining Wang,Feiwei Yu,Yunhai Ma
The objective of this study was to investigate the potential of using rice husk ash-derived silica (RHA-SiO₂) as a sustainable reinforcing agent for tread rubber composites. This investigation addresses the dearth of systematic research on the mechanical ball milling of RHA-SiO₂ by employing a central composite design within the response surface methodology to meticulously examine the impact of ball milling rotational speed, duration, and sample drying conditions on particle quality post-milling. The study's findings indicate that the rotational speed exerts the greatest influence on RHA-SiO₂ particle size, while drying state also emerges as a crucial factor influencing particle dispersion. The optimal ball milling parameters were identified as 240 r/min for 2 hours under anhydrous ethanol wetting conditions. Furthermore, it was demonstrated that RHA-SiO₂ could preserve the hardness and density of the composite, while simultaneously enhancing its stiffness and resilience by replacing industrial silica in the reinforced tread rubber composite. Notably, a 50% substitution rate resulted in a 23.1% enhancement in tear strength, demonstrating the efficacy of RHA-SiO₂ in bolstering the mechanical properties of rubber composites. Indeed, this work may offer new ways of high value use of agricultural waste and open new horizons for the development of high performance environmentally friendly tyre materials. Highlights RSM was utilized as a RHA-SiO 2 ultrafine ball milling technique with controlled particle size. The optimum ball milling process was 240 r/min for 2 h in the alcoholic state. RHA-SiO 2 exhibited a crystal structure and surface functional groups similar to the industrial silica. Replacement of industrial silica by RHA-SiO 2 improved the mechanical properties of tread rubber composites. RHA-SiO 2 at 50% substitution ratio increased tear strength by 23.1% to 41.76 kN/m.
研究领域:
材料科学
·
环境科学
·
橡胶工业
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2019
·
IF 3.42
Shiwei Guo,Di Wang,Junyou Shi,Xiu Li,Bin Feng,Linlong Meng,Zhaoyu Cai,Haoke Qiu,Shuangying Wei
Silica that originated from the calcination of rice husks, which is a source of biomass silicon, was added as a reinforcing agent to waterborne polyacrylate wood coatings to improve their coating performance, and especially their mechanical properties. The morphology of the rice-husk ash, aggregation and dispersion of modified silica in the polyacrylate emulsion and the surface roughness of the coating on wood were characterized by scanning electron microscopy, transmission electron microscopy and atomic force microscopy. The film mechanical properties and performance were investigated. The rice-husk ash calcined at 650 °C exhibited a particle size of 5–20 μm. Silica modified by silane coupling agent KH-570 was dispersed in waterborne acrylate coatings with a submicron scale. For a 2 wt% modified silica loading, the surface roughness of the coating on wood was influenced slightly and the elongation at break, the tensile strength, the elastic modulus, and the pencil hardness of the polyacrylate film were 303.06%, 48.673 MPa, 6.672 MPa and 2H level, respectively. The adhesion strength was enhanced significantly to level 0 with an increase in modified silica loading. The changes of film abrasion loss and gloss for the five groups are not obvious. The silica-modified coating exhibited slightly hydrophobic properties and a better lipophilicity. This paper provides a feasible route for the value-added utilization of rice husk.
研究领域:
材料科学
·
涂料技术
·
生物质利用
·
表面化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）