废聚苯乙烯泡沫塑料的催化裂解

为了对废聚苯乙烯泡沫塑料（WPS）资源化利用,通过对WPS进行催化裂解的方法,研究了催化剂种类和裂解温度对裂解时间、裂解油产率、苯乙烯回收率以及裂解油纯度的影响。研究结果表明,催化剂种类和裂解温度对裂解反应有着重要影响。裂解温度升高,裂解油产率提高,裂解时间缩短,但苯乙烯选择性下降;低于380 ℃时,氧化钙的裂解油产率和裂解时间优于氧化铝和氯化铝,但苯乙烯的选择性劣于氧化铝和氯化铝;高于400 ℃时,氯化铝、氧化铝和氧化钙的催化活性接近。在实验条件下,WPS催化裂解的最佳催化剂为氯化铝,380 ℃下的裂解时间为25 min,裂解油产率为85.48%,裂解油中苯乙烯含量为80.66%（w）,且副产物较少。     

废聚苯乙烯硝化氧化制对硝基苯甲酸

研究了用聚苯乙烯废料为原料,经过硝化氧化制造具有高附加值的精细化工产品－对硝基苯甲酸。探讨了影响对硝基苯甲酸产率的因素,如硝酸的浓度和用量,压力,反应时间及催化剂用量等。结果表明,在优化条件下对硝基苯甲酸产率达５２％,产品纯度为９９％。     

无皂乳液聚合改性废聚苯乙烯

以聚(甲基丙烯酸丁酯—丙烯酸钠)(P (BMA- AANa))为乳化剂,采用无皂乳液聚合技术,利用BMA对废聚苯乙烯(PS)泡沫塑料进行接枝改性.实验得出适宜的工艺条件:P(BMA - AANa)质量分数为51.5％,m(BMA)∶m(丙烯酸)=4∶6,PS和BMA质量分数之和为10.0％;m(PS)∶m(BMA) =...     

Investigation of Synthesis of Copolymers from the Waste Products of Industrial Oil Refinement having Adhesion Properties and Strength to the Thermal Destruction

In this study, the waste products of industrial vegetable oil refinement were transformed into the glycidyl ester for preventing the effects of them to the environment, the ways for evaluating them in polymer chemistry were investigated, copolymers having high adhesion property and strength to the thermal destruction were synthesized and the area of their usage was determined. For this reason, the waste product of sunflower oil refination as a vegetable oil in the industry; soap stock (SS) was converted to the unsaturated glycidyl esters by the interaction with epichlorohidrine in the alkaline medium. After that the copolymerization of synthesized unsaturated glycidyl esters and the other waste product of oil refinement fatty acid (FA) with styrene in the radicalic initiator medium were investigated and copolymers that have high strength to the thermal destruction and adhesion property were synthesized. From the results of TGA and DTA analysis, it was determined that synthesized copolymers have low loss of weight at high temperature. The structures of copolymers were fixed by spectral and chemical analysis methods.     

New Biopolymer Nanocomposite of Starch-Graft Polystyrene/Montmorillonite Clay Prepared Through Emulsion Polymerization Method

Starch-g-polystyrene (Starch-g-PS)/Montmorillonite nanocomposites were prepared via free-radical graft copolymerization of styrene and starch in the presence of montmorillonite clay, by emulsion polymerization method using potassium persulfate (KPS) as an initiator/catalyst and sodium dodecylbenzensulfonate (SDBS) as an emulsifier. The nanocomposites with different clay content 0, 2.5, 5.0, 7.5 and 10 weight percent of starch were prepared and the changes in layer-stacked structures of the clay particles in the resulted nanocomposite compounds were examined by using of X-ray diffraction and FT-IR spectroscopy. Finally the thermal degradation behavior and morphology of nanocomposites were studied using thermal gravimetric analysis (TGA) and SEM, respectively.     

Properties of Composite Panels Made from Tetra-Pak and Polyethylene Waste Material

The objective of this study was to evaluate some of the properties of experimental composite panels manufactured from waste packaging materials without using any additional binders. Particles from three types of materials, namely Tetra-Pak, food packaging films (FPEF) as recycled stretch wraps, and candy polyethylene wrappers (CPEW) were used at different ratios in the panels at a target density of 900 kg/m³. Modulus of rupture (MOR), screw holding strength and dimensional stability in the form of thickness swelling and water absorption of the panels were determined according to European (EN) standards. Based on the findings in this work it was determined that the ratio of different raw materials significantly influenced overall properties of the samples. The highest MOR value of 15.5 MPa was determined for the samples having 40 % Tetra-Pak and 60 % CPEW particles. Modulus of rupture values of the panels decreased with decreasing content of CPEW in the samples. The increased content of Tetra-Pak particles in the samples also resulted in reduction of their strength characteristics and dimensional stability. Properties of the samples considered in this work satisfied minimum requirements of typical particleboard stated in EN standards. It appears that such waste material would have potential to be used as raw material for value-added composite production using no adhesive in the panels and, therefore, such panels would possibly create significant ecological impact as green product.     

Converting Waste Polystyrene into Adsorbent: Potential Use in the Removal of Lead and Cadmium Ions from Aqueous Solution

Waste of polystyrene was converted into a cation exchange resin and was used for the removal of lead and cadmium metals from aqueous solution. Wastes consisting of coffee cups were crushed into small pieces and immersed into a solution of sulfuric acid in order to attach sulfonic group to polymer chain, these groups are responsible for the exchange properties of the modified plastic. The cation exchange capacity (CEC) was determined and was comparable to commercial exchangers. The adsorption isotherms of resin with synthetic wastewater containing lead and cadmium ions were tested. Adsorption analysis results obtained at various concentrations showed that the adsorption pattern on the resin followed Langmuir isotherms.     

Effects of Saturated Acids on Physical Properties of UPE Resins Prepared from Recycled PET Products

In this study, effects of saturated acids on physical properties, including hardness, impact strength, flexural properties and thermal properties, of unsaturated polyester or UPE resins prepared from recycled PET bottles and fabrics were investigated. PET was depolymerized by glycolysis reaction with the excess propylene glycol in the presence of zinc acetate as a catalyst. UPE resins were then synthesized by polyesterification of these glycolyzed products with maleic anhydride as an unsaturated diacid as well as succinic acid and adipic acid as a saturated diacid. With the addition of styrene monomer, UPEs were subsequently casted into specimens by crosslinking reaction using methyl ethyl ketone peroxide and cobalt octoate as an initiator and a catalyst, respectively. Physical properties of the cured specimens were then studied. The results showed that, when a saturated acid was incorporated, the hardness of the cured UPE resins decreased due to the decreasing amount of crosslinks. The extended distance between crosslinking sites on molecular chains facilitated load distribution, resulting in the significant improvement of impact strength. The flexural strength was also improved when the small amount of saturated acid was used. The onset thermal degradation temperatures and the glass transition temperatures of the prepared UPE resins were almost unchanged.     

Synthesis and Properties of Polyesters from Waste Grapeseed Oil: Comparison with Soybean and Rapeseed Oils

The aim of this study was to investigate the application of grapeseed oil, a waste product from the wine industry, as a renewable feedstock to make polyesters and to compare the properties of these materials with those derived from soybean and rapeseed oils. All three oils were epoxidized to give renewable epoxy monomers containing between 3.8 and 4.7 epoxides per molecule. Polymerisation was achieved with cyclic anhydrides catalysed by 4-methyl imidazole at 170 and 210 °C. Polymers produced from methyl tetrahydrophthalic anhydride (Aradur917^®) had greater tensile strength and Young’s Modulus (tensile strength = 12.8 MPa, Young’s Modulus = 1005 MPa for grapeseed) than methyl nadic anhydride (MNA) derived materials (5.6 and 468 MPa for grapeseed) due to increased volume of MNA decreasing crosslink density. Soybean and grapeseed oils produced materials with higher tensile strength (5.6–29.3 MPa) than rapeseed derived polyesters (2.5–3.9 MPa) due to a higher epoxide functionality increasing crosslinking. T _g’s of the polyesters ranged from ?36 to 62 °C and mirrored the trend in epoxide functionality with grapeseed producing higher T _g polymers (?17 to 17 °C) than soybean (?25 to 6 °C) and rapeseed (?36 to ?27 °C). Grapeseed oil showed similar properties to soybean oil in terms of T _g, thermal degradation and Young’s Modulus but produced polymers of lower tensile strength. Therefore grapeseed oil would only be a viable substitute for soybean for low stress applications or where thermal properties are more important.     

Headspace-SPME-GC-MS Identification of Volatile Organic Compounds Released from Expanded Polystyrene

A method for the identification of volatile organic compounds (VOCs) released from packaging expanded polystyrene (EPS) is presented. Headspace solid-phase microextraction (HS-SPME) with a 75-m carboxen-polydimethylsiloxan fiber was used as sample preparation technique before the determination of the volatile organic compounds by gas chromatography–mass spectrometry (GC-MS). For separation of compounds, two fused silica capillary columns of different polarity (DB-5ms and BPX-50) were used. Styrene monomer with his impurities and oxidation products, as well as residual pentane, were identified in the headspace of EPS.     

Material Properties and Influence of Molecular Weight and Testing Rate on Adhesion Properties of Epoxidized Natural Rubber-Based Adhesives

The effect of molecular weight and testing rate on peel and shear strength of epoxidized natural rubber (ENR-50)-based adhesive was investigated using petro resin as the tackifier. Toluene and polyethylene terephthalate were used as the solvent and substrate respectively. Peel and shear strength were determined by a Llyod Adhesion Tester operating at different rates of testing. Result shows that peel strength and shear strength increases up to an optimum molecular weight of 4.2 × 10⁴ g/mol of ENR-50. This observation is attributed to the combined effects of wettability and mechanical strength of rubber for peel strength. For shear strength, it is ascribed to the optimum cohesive and adhesive strength. Both peel strength and shear strength increases with increasing rate of testing, an observation which is associated to the viscoeslastic response of the adhesive. Thermal study, SEM and FTIR study confirms the miscibility of tackifier with ENR-50.     

Effect of Hybrid Tackifiers on Adhesion Properties of Epoxidized Natural Rubber-Based Pressure-Sensitive Adhesives

Viscosity, peel and shear strength of epoxidized natural rubber (ENR)-based pressure-sensitive adhesive was studied by using hybrid tackifiers consisting of a mixture of coumarone-indene resin and petro resin. The coumarone-indene resin concentration was fixed at 40 parts per hundred parts of rubber (phr). The concentration of petro resin, however, was varied from 20 to 80 phr. Toluene and polyethylene terephthalate (PET) film were used as the solvent and coating substrate respectively throughout the experiment. Viscosity of adhesive was determined by a HAAKE Rotary Viscometer whereas peel and shear strength was measured by a Lloyd Adhesion Tester. Results show that viscosity and shear strength decreases with increasing petro resin concentration. However, peel strength exhibits a maximum value at 40 phr petro resin, an observation which is attributed to maximum wettability and compatibility of adhesive on the substrate. ENR 25-based adhesive exhibits higher viscosity and peel strength but lower shear strength compared to the ENR 50 adhesive system.     

Effect of Metal Oxide Catalysts on Degradation of Waste Polystyrene in Hydrogen at Elevated Temperature and Pressure in Benzene Solution

Degradation of waste polystyrene is carried out in presence of hydrogen using several metal oxide catalysts at elevated temperature and pressure for recycling. Benzene is used as a solvent for degradation. Initial hydrogen pressure in the autoclave is kept at 7.0 kg/cm² (g) and polystyrene degradation is carried out at 240 °C. After degradation, degraded polystyrene residue is separated and analyzed by Fourier transform infra red (FTIR) spectroscopy whereas filtrate is analyzed by gas chromatography (GC) for finding the degradation mechanism of polystyrene. Degradation rate is enhanced in presence of hydrogen and time dependent weight average molecular weight of degraded polystyrene is determined using viscosity method. Degradation rate constants for the different catalysts are calculated based on the proposed degradation mechanism. Alkali metal oxide catalyst shows higher reactivity towards polystyrene degradation as compare to the transition metal oxide catalyst i.e., degradation rate constant decreases with the increase in electro negativity of metal element of the catalyst. Though manganese (IV) oxide is a transition metal catalyst, but shows higher reactivity due to its reduction towards stable manganese (II) oxide under degradation environment. Finally, degradation rate constant of polystyrene is correlated with the catalyst activity i.e., electro negativity of metal element in the catalyst.     

Hybrid Composites from Waste Materials

Hybrid composites of thermoplastic biofiber reinforced with waste newspaper fiber (NF) and poplar wood flour (WF) were prepared. The weight ratio of the lignocellulosic materials to polymer was 30:70 (w:w). Polypropylene (PP) and maleic anhydride grafted polypropylene (MAPP) were also used as the polymer matrix and coupling agent, respectively. The mechanical properties, morphology and thermal properties were investigated. The obtained results showed that tensile and flexural modulus of the composites were significantly enhanced with addition of biofibers in both types (fiber and flour), as compared with pure PP. However, the increasing in WF content substantially reduced the tensile, flexural and impact modulus, but improved the thermal stability. This effect is explained by variations in fiber morphological properties and thermal degradation. Increasing fiber aspect ratio improved mechanical properties. The effect of fiber size on impact was minimal compared to the effects of fiber content. Scanning electron microscopy has shown that the composite, with coupling agent, promotes better fiber–matrix interaction. The largest improvement on the thermal stability of hybrid composites was achieved when WF was added more. In all cases, the degradation temperatures shifted to higher values after addition of MAPP. This work clearly showed that biofiber materials in both forms of fiber and flour could be effectively used as reinforcing elements in thermoplastic PP matrix.     

Effect of Cotton Fiber Contents and Lengths on Properties of Thermoplastic Starch Composites Prepared from Rice and Waxy Rice Starches

Biodegradable polymer was prepared as thermoplastic starch (TPS) using rice and waxy rice starches. In order to increase mechanical properties and reduce water absorption of the TPS, cotton fiber was incorporated as the fiber reinforcement into the TPS matrix. The effect of cotton fiber contents and lengths on properties of the TPS was examined. Internal mixer and compression molding machine were used to mix and shape the samples. It was found that the thermoplastic rice starch (TPRS) showed higher stress at maximum load and Young’s modulus but lower strain at maximum load than the thermoplastic waxy rice starch (TPWRS). In addition, stress at maximum load and Young’s modulus of both TPRS and TPWRS increased significantly with the addition of the cotton fiber. Cotton fiber contents and lengths also affected mechanical properties of the TPRS and TPWRS composites. Moreover, water absorption of the TPRS and TPWRS composites decreased by the use of the cotton fibers. FT-IR and XRD techniques were used to study a change in functional group and crystallinity of the thermoplastic starch composites. Morphological, thermal and biodegradable properties of different thermoplastic starch composites were also investigated.     

生物滴滤塔处理氯苯废气的工艺性能

将活性污泥培养及驯化后接种于生物滴滤塔中,挂膜启动后处理模拟氯苯废气（简称氯苯废气）,考察了生物滴滤塔在挂膜启动阶段及稳定运行阶段的性能。实验结果表明：接种41 d后生物滴滤塔成功挂膜,此时氯苯去除率稳定在90%以上;生物滴滤塔稳定运行阶段,随着进气中氯苯质量浓度由303.82 mg/m³逐渐增至1 489.05 mg/m³,氯苯去除率从85.1%降至70.1%。处理氯苯废气适宜的工艺条件为：空塔停留时间超过45 s,喷淋液流量31.8 mL/min,氯苯负荷23.97~128.01 g/（m³·h）。生物滴滤塔对喷淋液的酸性环境有较好的适应性,喷淋液pH的变化对氯苯去除率无显著影响。     

Properties of Glauconite/Polyaniline Composite Prepared in Aqueous Solution of Citric Acid

Hybrid composite made of glauconite and polyaniline was prepared in aqueous solution of citric acid. Scanning electron microscopy combined with energy dispersive X-ray analysis shows uniform aggregates made of glauconite microparticles and polyaniline matrix. The results of X-ray powder diffraction suggest that: (1) citric acid used for the polymerisation of aniline causes formation of emeraldine salt where macromolecular ordering in the amorphous polymer takes place; (2) no chemical interaction between glauconite and emeraldine takes place in the prepared composite. FT-IR spectra of the prepared polymer and composite show features indicating all the functional groups that are present in the diiminoquinone–diaminobenzene state of polyaniline. Thermal stability of the composite was higher than the prepared polymer suggesting the occurrence of an interphase interaction between glauconite and emeraldine. After pyrolysis in purified nitrogen the composite still remained glauconite, and ε-Fe3N together with amorphous and graphitic carbon were found as reaction products. The values of electrical conductivity and magnetization of the composite suggest that optimization of these values might be achieved based upon the relationship between glauconite and polyaniline.     

含镍废催化剂的回收利用

介绍了从含镍废催化剂中以硝酸镍形式加收镍的方法，镍回收率为70％，硝酸镍纯度为96．6％。该工艺简单，具有较好的经济效益和环境效益。     

Effects of Sodium Bisulfite on the Physicochemical and Adhesion Properties of Canola Protein Fractions

This study focused on investigating the potential of using canola protein fractions as bio-degradable wood adhesives. Native and sodium bisulfite (NaHSO₃)-modified canola protein fractions isolated successively at different pH values (7.0, 5.5, and 3.5) was used as adhesives. Wood specimens were assembled with adhesives at a pressure of 2?MPa at 150, 170, or 190?°C for 10?min. The adhesion performance of adhesives were evaluated by wet, soak, and dry shear strength. Their physicochemical properties: extractability, electrophoresis profiles, thermal, rheological and morphological properties were also characterized. Results showed that canola protein had the highest protein yield and purity at pH 5.5. Electrophoresis profile proved that NaHSO₃ cleaved the disulfide bonds in canola protein. This could induce extra charges (RS-SO₃ ^?) on the protein surface, leading to the reduced apparent viscosity. Thermal analysis implied that the thermal transition temperature of canola protein decreased with modification of NaHSO₃. Canola protein adhesives showed excellent dry and soak shear strength with 100?% wood cohesive failure in all curing temperatures. The wet adhesion strength of native and modified canola protein fraction adhesives at pH 5.5 and pH 3.5 (3.9?C4.1?MPa) was higher than the fractions at pH 7.0. NaHSO₃ had insignificant effects on the adhesion performance of canola protein adhesives but notably improved the handling and flow-ability properties of canola protein adhesives.     

Effect of Shrimp Shell Waste on the Properties of Wheat Gluten Based-Bioplastics

Wheat gluten based bioplastics with shrimp shell waste filler were prepared using compression molding. The effects of various amounts (0, 2.5, 5.0, 7.5 and 10 wt%) of shrimp shell powder and calcined shrimp shell powder on the tensile, morphological, thermal properties, and degradation of wheat gluten composites were investigated. The addition of shrimp shell powder improved the tensile properties of the wheat gluten composites. The tensile strength of the wheat gluten composite with 2.5 wt% of shrimp shell powder increased twofold compared to the wheat gluten based-bioplastic without shrimp shell loading. A comparison of the performance of the wheat gluten composites made with different shrimp shell types revealed that composites with calcined shrimp shell powder had better tensile, morphological and thermal properties due to the altered layer structure and higher mineral content resulting from calcination. Moreover, calcined shrimp shell powder had a significant influence on the degradation process of the wheat gluten composite.