共查询到19条相似文献,搜索用时 46 毫秒
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以H3PO4为活化剂制备甘蔗叶活性炭,采用正交实验对活性炭的制备工艺进行了优化,并研究了活性炭对含铬废水的吸附和再生性能.实验结果表明:在H3PO4体积分数为15%、H2SO4体积分数为6%、HC1体积分数为3%、活化温度为723 K、活化时间为0.58 h的工艺条件下,活性炭得率为35.07%,碘吸附值为1 207 mg/g.活性炭对Cr(Ⅵ)的最大平衡吸附量为30.89 mg/g,HNO3再生后对Cr(Ⅵ)的最大平衡吸附量为39.48 mg/g;再生效率最高达87.41%,经3次再生,活性炭的再生效率仍能维持在80%以上. 相似文献
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钛白废酸中硫酸亚铁的分离及废酸回收 总被引:5,自引:0,他引:5
用二级浓缩法来回收钛白废酸。根据硫酸亚铁在硫酸溶液中的溶解度数据,着重讨论了常压浓缩、熟化结晶和真空浓缩的工艺条件。废酸在分离硫酸亚铁后,其浓度达80%(重量)以上,可回用于钛白生产中。此外,还讨论了滤渣打浆问题。 相似文献
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将废RK-05甲醇合成催化剂经过煅烧、浸取、精制等工序回收其中的铜和锌。经正交实验得到煅烧废催化剂的最优工艺参数为:废催化剂筛目100目,煅烧温度950℃,煅烧时间60 min。最佳浸取工艺条件为:废催化剂加入量约4 g/L,浸取温度75℃,浸取剂用量与理论用量体积比2.0~3.0,浸取剂浓度4.0 mol/L,浸取时间10min。精制工序制备CuO的最佳工艺条件为:锌粒与滤渣质量比为1.00,反应时间3 h,煅烧温度450℃,煅烧时间4 h。制备ZnO的最佳工艺条件为:煅烧温度800℃,煅烧时间60 min。回收的产品CuO纯度为99.1%,满足GB/T674—2003《化学试剂粉状氧化铜》中优级品的标准。回收的产品ZnO纯度为99.6%,满足GB/T3185—1992《氧化锌(间接法)》中一级品的标准。 相似文献
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我国中、小型硫酸生产中 ,仍有一些厂家采用一转一吸工艺流程 ,二氧化硫的转化率约为 90 %~95%。含 SO2 的炉气虽经转化吸收 ,排放尾气中 SO2的含量仍在 0 .4 %~ 0 .5% (质量分数 )。一家年产 4 .5万 t的硫酸厂 ,排放尾气中的 SO2 可达 540 0 t,既浪费资源 ,又污染环境。尾气的回收势在必行。目前 ,SO2 回收方法中应用较多的为氨酸法 ,但由于此法选用的设备结构及操作条件不尽合理 ,使尾气很难达到国家排放标准。我们采用氨酸法对某硫酸厂尾气的回收工艺条件及设备进行合理选择 ,不仅使尾气达到国家排放标准 ,同时生产出合格的液体 SO… 相似文献
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Journal of Polymers and the Environment - The bio-based acoustic materials have flourished with the future depletion of petroleum resources in recent years. This paper dedicates on the synthesis of... 相似文献
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Wei Seng Ng Choy Sin Lee Sit-Foon Cheng Cheng Hock Chuah Shew Fung Wong 《Journal of Polymers and the Environment》2018,26(7):2881-2900
Biodegradable polyester polyol was synthesized from oleochemical glycerol monostearate (GMS) and glutaric acid under a non-catalyzed and solvent-free polycondensation method. The chemical structure of GMS-derived polyester polyol (GPP) was elucidated by FTIR, 1H and 13C NMR, and molecular weight of GPP was characterized by GPC. The synthesized GPP with acid value of 3.03 mg KOH/g sample, hydroxyl value of 115.72 mg KOH/g sample and Mn of 1345 g/mol was incorporated with polyethylene glycol (PEG) and polycaprolactone diol (PCL diol) to produce a water-blown porous polyurethane system via one-shot foaming method. The polyurethanes were optimized by evaluating glycerol as a crosslinker, silicone surfactant and water blowing agent on tensile properties of polyurethanes. All polyurethanes underwent structural change, and crystalline hard segments of polyurethanes were shifted to higher temperature suggested that hard segments undergone re-ordering process during enzymatic treatment. In terms of biocompatibility, polyurethane scaffold produced by reacting 100% w/w of GPP with isophorone diisocyanate and additives showed the highest cells viability of 3T3 mouse fibroblast (94%, day 1), and MG63 human osteosarcoma (107%, day 1) and better cell adhesion as compared to reference polyurethane produced by only PEG and PCL diol (3T3 cell viability: 8%; MG63 cell viability: 2%). The current work demonstrated GPP synthesized from renewable and environmental friendly resources produced polyurethanes that allows improvement in physico-chemical, mechanical and biocompatibility properties. By blending with increasing content of GPP, the water-blown porous polyurethane scaffold has shown great potential as biomaterial for soft and hard tissue engineering. 相似文献
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This paper describes the effect of the modification of polyurethane system with palm oil-based polyol on the cell structure and physical?Cmechanical properties of polyurethane foams. Flexible polyurethane foams were prepared by substituting a part of petrochemical polyether-polyol with the palm oil polyol. Selected physical?Cmechanical properties of these foams were examined and compared to the properties of reference foam. The properties such as apparent density, tensile strength, elongation at break, resilience, compressive stress and thermal stability were analyzed. It was found that the modifications of polyurethane formulation with palm oil polyol allow to improve selected properties of final products. 相似文献
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Journal of Polymers and the Environment - Epoxy resin (EP) is a thermosetting resin with prominent performances and wide applications. However, the inherent brittleness limits its development in... 相似文献
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Influence of Polyol Plasticizers on the Properties of Polyvinyl Alcohol Films Fabricated by Melt Processing 总被引:1,自引:0,他引:1
In this work, high-alcoholysis polyvinyl alcohol (PVA) films were fabricated by melt processing and the plasticizing effect
of compound polyol plasticizers on PVA were investigated with X-ray diffraction (XRD), differential scanning calorimetry (DSC),
rheological measurements, mechanical tests etc. Hydrogen bonding interactions occurred between PVA and plasticizer. With the
increase of plasticizer, the flowability of PVA was improved and reached the maximum value at the plasticizer of 20%. Glass
transition temperature (T
g) and melting point (T
m) decreased with the increase of plasticizer content. For the heterogeneous nucleation effect of plasticizer, new polymorph
of PVA formed. The viscosity was sensitive to the shear rates. The incorporation of plasticizers into PVA resulted in the
increase of elongation at break and impact strength, as well as the decrease of tensile strength. 相似文献
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Wu GuangFeng Song Xin Yang ZhiHui Li YingChun Zhang HuiXuan 《Journal of Polymers and the Environment》2022,30(2):528-540
Journal of Polymers and the Environment - Polyester diol PCL and PBA, polyether diol PTMG and polycarbonate diol PCDL were used as components of WPU soft segment, respectively. Polyether PTMG-WPU... 相似文献
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Synthesis of Segmented Polyurethane Based on Polymeric Soybean Oil Polyol and Poly (Ethylene Glycol)
Polyurethane (PUR) plastic sheets were prepared by reacting hydroxylated polymeric soybean oil (PSbOH) synthesized from autoxidized
soybean oil with polyethylene glycol (PEG) in the presence of isophorone diisocyanate (IPDI). FTIR technique was used to identify
of chemical reactions. These polyurethanes have different valuable properties, determined by their chemical composition. The
effect of stoichiometric balance (i.e., PSbOH/PEG-2000/IPDI weight ratio) on the final properties was evaluated. The polyurethane
plastic sheets with the PSbOH/PEG-2000/IPDI weight ratio 1.0/1.0/0.67 and 1.0/0.3/0.3 had excellent mechanical properties
indicating elongation at break more than 200%. Increase in IPDI and decrease in PEG weight ratio cause the higher stress–strain
value. The properties of the materials were measured by differential scanning calorimetry (DSC), thermo gravimetric analysis
(TGA), stress–strain measurements and FTIR technique. 相似文献
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Jin-San Kim Tara Sankar Pathak Jung-Ho Yun Ki-Pal Kim Tae-Joon Park Yongae Kim Ki-Jung Paeng 《Journal of Polymers and the Environment》2013,21(1):224-232
Alginate polyurethane hybrid materials are prepared by varying mole ratio of 2, 4-TDI as a di-isocyanate and alginic acid as a polyol in presence of dimethyl sulfoxide (DMSO) as a solvent. FT-IR and 13C one-dimensional (1D) solid state NMR (SSNMR) spectroscopy indicates that alginic acid is converted into alginate-polyurethane hybrid material via urethane linkage. Surface morphology of alginate-polyurethane hybrids changes by varying alginic acid: TDI ratio. The peak at near 221 °C in DSC thermogram of alginic acid (Alg) is shifted to higher temperature in alginate-polyurethane hybrid (Algpu1 and Algpu2). TGA study shows that alginate-polyurethane hybrid prepared using alginic acid: TDI = 1:1 (Algpu2) is more stable than alginic acid: TDI = 1:0.5 (Algpu1) at 300 °C. Kinetic analysis was performed to fit with TGA data, where the entire degradation process has been considered as three consecutive 1st order reactions. This study shows that thermal stability of alginate-polyurethane hybrid material was increased by adjusting mole ratio of 2, 4-TDI and alginic acid. 相似文献