共查询到20条相似文献,搜索用时 15 毫秒
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从废感光胶片中回收银 总被引:2,自引:0,他引:2
研究了以Fe3 -乙二胺四乙酸二钠-N a2S2O3体系为浸取剂从废感光胶片中回收银的方法,考察了浸出银的最佳工艺条件。实验表明,当浸取剂中FeC l3.6H2O质量浓度为35g/L、N a2S2O3.5H2O质量浓度为150g/L、pH为7、固液质量比为3∶10时,浸取剂可重复使用6次,胶片上银的浸出率可达99%以上;浸取液中的银采用硼氢化钠还原回收,粗银粉配以熔剂高温熔炼可得到纯度达99.78%的银,银回收率达96.88%,回收银后的浸取液可循环使用。 相似文献
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Bakti B. Sedayu Marlene J. Cran Stephen W. Bigger 《Journal of Polymers and the Environment》2018,26(9):3754-3761
Carrageenan-based films demonstrate good performance, the raw materials for their production are abundant in nature and can be sustainably sourced from seaweeds. Similar to other naturally-derived biopolymers, however, carrageenans are relatively expensive to purify and form into useful materials. In order to potentially lower the production costs compared to pure carrageenan, semi-refined carrageenan (SRC) plasticized with 0–50% (w/w) glycerol was investigated using a solution casting method. The film color and opacity increased along with the moisture content, whereas the water vapor permeability decreased with increasing levels of glycerol. The tensile properties of the SRC films improved significantly, particularly at glycerol additions greater than 30% (w/w). Moreover, the addition of glycerol improved the thermal stability and altered the surface morphology of the films. In general, the properties of the SRC films were comparable with refined carrageenan films suggesting that SRC has potential to be furthered developed into more cost effective primary food packaging materials. 相似文献
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薄膜负载型TiO_2光催化降解乙酸 总被引:1,自引:0,他引:1
利用TiCl_4水解法在玻璃表面制备纳米TiO_2光催化膜,考察了TiO_2光催化膜对乙酸光催化降解过程的影响因素.实验结果表明:使用活化温度为460℃、镀膜4次、表面积168 cm~2的TiO_2光催化膜处理500 mL0.667 mmoL/L的乙酸350 min时,乙酸降解率为80.0%,与等量TiO_2粉末相比光催化膜活性显著增加;当乙酸初始浓度c_0小于0.667 mmoL/L时,光催化降解过程可用Langmuir-Hinshelwood动力学方程来描述;TiO_2膜连续使用5次(30 h)时的光催化活性基本不变;用质量分数为5%的HCl溶液浸泡失去活性的光催化膜1 h,TiO_2光催化膜的活性可完全恢复. 相似文献
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de Oliveira Ana Carolina Salgado Ferreira Laura Fonseca de Oliveira Begali Danielly Ugucioni Julio Cesar de Sena Neto Alfredo Rodrigues Yoshida Maria Irene Borges Soraia Vilela 《Journal of Polymers and the Environment》2021,29(8):2546-2556
Journal of Polymers and the Environment - Researches for the development of materials with less environmental impact have been more common. Pectin is a natural polysaccharide, presenting in plants... 相似文献
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Currently, there is an environmental pollution problem generated in part by packaging materials produced from non-biodegradable synthetic polymers made from petroleum. However, these can be replaced with biodegradable materials made from cassava starch (CS) and natural rubber (NR). In the work described, a novel biopolymer film was obtained from the CS and NR using glycerol (GE) as a plasticizer in a water-based system. The physical properties of an 95/5 CS/NR blend films with the addition of NR and with varying GE contents were studied based on their swelling ratio, moisture content, moisture absorption, mechanical properties and biodegradability in soil. The results showed that the moisture content and moisture absorption tended to be directly proportional to the GE content, while the moisture content and moisture absorption of the sample decreased as a function of the NR content. The swelling ratio of the 95/5 CS/NR blend slightly decreased as a function of the NR and GE content. Surprisingly, the best swelling ratio of 350% was found at 10% NR. The elongation at break of the CS/NR blend was improved by the addition of GE. The contact angle of the 95/5 CS/NR blend decreased as a function of the GE. With increased NR in the composite, an increasing, trend in the contact angle was found. Further, the 95/5 CS/NR blend exhibited good transparency when it was applied as a coating to delay the ripening of bananas, the results were positive. Moreover, the film showed decomposition well in natural soil. 相似文献
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生物膜法A/O系统处理己内酰胺废水 总被引:4,自引:1,他引:3
采用缺氧-好氧淹没式生物膜系统处理己内酰胺废水,着重探讨了碳源对硝化、反硝化的影响.研究结果表明:缺氧池进水中可生物降解COD与NO x-N的质量比必须大于3,好氧池COD负荷应小于0.98kg/(m3.d),系统才能有效地同时脱氮和去除COD. 相似文献
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Hisaaki Yagi Fumi Ninomiya Masahiro Funabashi Masao Kunioka 《Journal of Polymers and the Environment》2012,20(3):673-680
The anaerobic biodegradation rates of four different sizes of poly (lactic acid) (PLA) films (thickness 25???m) in anaerobic sludge at 55?°C were examined. The anaerobic biodegradation rates of small pieces of PLA film were slower than for large pieces of PLA film. We also examined whether PLA film could also be used as a reference material in the anaerobic biodegradation test in addition to PLA powder. The anaerobic biodegradation rate of PLA film became slower with lower activity sludge, but the rate of decrease was gradual, and the anaerobic biodegradation rate of PLA film was faster than the PLA powder (125?C250???m). The anaerobic biodegradation rate of the PLA powder (125?C250???m) reflected the plastic anaerobic biodegradation activity of the sludge more accurately than the thin PLA film (thickness 25???m). Consequently, PLA powder (125?C250???m) is more suitable than thin PLA film (thickness?<?25???m) for use as a reference material to assess the plastic anaerobic biodegradation activity of the sludge in an anaerobic biodegradation test at 55?°C. 相似文献
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A. M. Abdel Ghaffar H. E. Ali Sh. M. Nasef Heba A. El-Bialy 《Journal of Polymers and the Environment》2018,26(8):3226-3236
Chitosan nano-composite film crosslinked by citric acid and with glycerol as plasticizer and MgO as antibacterial agent was prepared by casting method. MgO nanoparticles were synthesized via calcination method in furnace at 500 °C for 4 h and characterized by X-ray diffraction and transmission electron microscope. The chitosan nano-composite film with composition chitosan/citric/glycerol/magnesium oxide (1 wt%:1 wt%:75 vol%:10 wt%) has high mechanical properties than other films. The effects of different irradiation doses on the mechanical, thermal and antibacterial activity were investigated. The tensile strength enhanced by increasing irradiation dose up to 10 kGy and the elongation negligible changed as irradiation dose increased. The thermal stability slightly increased up to dose 2.5 kGy then decreased with dose increment. The antimicrobial activity film was studied against white mulberry-borne bacterial pathogens either Gram positive or Gram negative bacteria and has positive impact of gamma irradiation on the antimicrobial activity. The use of the selected chitosan nano-composite film which irradiated by dose of 2.5 kGy and has magnesium oxide of average particle size 54.3 nm as new packaging materials found to improve storage quality and shelf-life of mulberry fruit. 相似文献
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Preparation and Characterization of Compatible and Degradable Thermoplastic Starch/Polyethylene Film 总被引:2,自引:0,他引:2
The degradability of the compatible thermoplastic starch/polyethylene film was investigated by weight loss percent (WLP),
Fourier Transform Infrared (FT-IR) Spectroscopy, and Scanning Electron Microscope (SEM). The compatible film was prepared
by using the particles of thermoplastic starch/polyethylene blends that were produced by one-step reactive extrusion. The
weight of the film after degradation reduced more than 3% for 30 days and 4% for 60 days. The FTIR results revealed that both
starch and polyethylene in the film exhibited varying degrees of degradation. SEM photographs of the films after degradation
showed that starch particles in the film disintegrated into smaller particles or separated out of the film surface. Degradation
studies demonstrated that the compatible thermoplastic starch/polyethylene film had increased degradability at the given degradable
environment. The information implies that this film could be utilized as a degradable plastic. 相似文献
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Sanna Virtanen Ravindra Reddy Chowreddy Sibel Irmak Kaisu Honkapää Loren Isom 《Journal of Polymers and the Environment》2017,25(4):1110-1130
Vast amounts of co-streams are generated from plant and animal-based food processing industries. Efficient utilization of these co-streams is important from an economic and environmental perspective. Non-utilization or under-utilization of co-streams results in loss of potential revenues, increased disposal cost of these products and environmental pollution. At present, extensive research is taking place around the globe towards recycling of co-streams to generate value-added products. This review evaluates various co-streams from food processing industries as raw materials in developing biodegradable agricultural mulching applications. Among the agriculture-based co-streams, potato peels, tomato peels, carrot residues, apple pomace, coffee residues and peanut residues were reviewed with respect to production amount, composition, film forming components and film forming capabilities. Similarly, selected co-streams from slaughterhouses, poultry and fish processing industries were also reviewed and evaluated for the same purpose. 相似文献
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为研究Zn^2+/TiO2薄膜光催化剂对NO的去除效果,以钛酸四正丁酯和Zn(NO3)2为前驱体、石英玻璃片为基片,用在溶胶中进行浸渍提拉的方法,于500℃下煅烧制备出Zn^2+加入量不同的Zn^2+/TiO2薄膜光催化剂,重点考察了Zn^2+加入量对NO去除率的影响。实验结果表明,Zn^2+的加入可进一步提高NO的去除率,当Zn^2+加入量为4%时,NO最高去除率为89%。对各种试样的扫描电镜和X射线衍射表征结果表明,适当加入Zn^2+可改善纳米TiO2的分散状态,减小粒径尺寸,从而达到提高NO去除率的目的。 相似文献
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Alarming environmental pollution from petroleum based non-biodegradable disposable packaging films has generated concern for development of alternatives from natural polymers such as starch. In the present work, the biodegradability of a self-supporting film made from starch and polyvinyl alcohol (PVA) (starch:PVA?=?9:1 as the polymer) together with glutaraldehyde as crosslinker and sodium propionate (SP) as antimicrobial was investigated by soil burial method. The changes in soil composition namely pH, organic carbon, available and total nitrogen, and water holding capacity as a result of biodegradation were also estimated. The film underwent ≈?90% biodegradation within a period of 28 days, with simultaneous increase in soil nutrients. Moreover, the pH remained in the accepted limit for plant growth. Thus, antimicrobial in the film did not hamper its biodegradation, rather disposal of the film in soil might facilitate plant growth. 相似文献
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Choonut Aophat Prasertsan Poonsuk Klomklao Sappasith Sangkharak Kanokphorn 《Journal of Polymers and the Environment》2021,29(10):3335-3346
Journal of Polymers and the Environment - In this study, a novel medium-chain-length polyhydroxyalkanoate (mcl-PHA) film containing 39.25 mol% 3-hydroxyhexadecanoic acid... 相似文献
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Richa Modi Romil Mehta H. Brahmbhatt A. Bhattacharya 《Journal of Polymers and the Environment》2017,25(4):1140-1146
The study investigated the use of thin film composite membrane (TFC) as a potential candidate for hydroquinone removal from water. Thin film composite membranes were prepared by polyamide coating on Polysulfone asymmetric membrane. FTIR study was performed to verify the Polysulfone as well as polyamide functionality. TFC membrane was characterized by contact angle, zeta potential, scanning electron microscopy studies. The salt rejection trend was seen from 500 to 1000 mg/L. The membrane is marked by permeability co-efficient B based on solution diffusion studies. The value is 0.98 × 10?6 m/s for NaCl solution at 1.4 MPa. The separation performance was 88.87% for 5 mg/L hydroquinone at 1.4 MPa. The separation was little bit lowered in acid medium because of the nature of the membrane and feed solute chemistry. The ‘pore swelling’ and ‘salting out’ influenced hydroquinone separation in the presence of NaCl. The hydroquinone separation was 80.63% in 1000 mg/L NaCl solution. In acidic pH, NaCl separation was influenced much more compared to hydroquinone. The separation is influenced by field water matrix. 相似文献