Rubber sheet strewn with TiO2 particles:Photocatalytic activity and recyclability

A new method for the preparation of rubber sheet strewn with titanium dioxide particles (TiO₂-strewn sheet) is presented. This simple and low cost method is based on the use of TiO₂ powder (Degussa P25) being strewn onto the sheet made from rubber latex (60% HA) through a steel sieve. The characteristic of the TiO₂-strewn sheet was studied by using scanning electron microscopy/energy dispersive X-ray spectrometer (SEM/EDS) and X-ray diffractometer (XRD) techniques. The photocatalytic activity of TiO₂-strewn rubber sheet was evaluated using Indigo Carmine (IC) dye as a model for organic dye pollutant in water. The results showed that the TiO₂-strewn sheet could degrade IC dye solution under UV light irradiation. The effects of pH, initial concentration, and the intensity of UV light on the photodegradation were also investigated. Kinetics of the photocatalytic degradation was of the first-order reaction. The used TiO₂-strewn sheet can be recovered and reused. The recycling uses did not require any cleaning between successive uses and no decline in the photodegradation efficiency was observed compared with freshly prepared TiO₂-strewn sheet.     

三元乙丙橡胶防水卷材热解分析

采用热重-差热联动分析仪对三元乙丙橡胶(EPDM)防水卷材进行了热解特性研究,同时分析了升温速率以及不同气氛对热解行为的影响,并采用Flynn-Wall-Ozawa多升温速率法和Coats-Redfern单升温速率法分别求解了样品在氮气气氛以及空气气氛下的动力学参数,以此作为基础数据开发室外屋面防灭火系统,对减少人员伤亡和经济损失具有重要意义。     

氟醚橡胶在不同介质下的热老化行为与机理研究

目的 对氟醚橡胶FM-2D在空气与飞马Ⅱ号润滑油中的热老化行为与机理进行研究。方法 开展氟醚橡胶高温贮存试验,在热氧、热油的介质环境下,研究氟醚橡胶的力学性能退化规律。试验后对样品的拉伸性能、压缩性能以及硬度进行检测,并且利用傅里叶红外光谱仪、扫描电子显微镜以及X射线电子能谱对试验后样品进行检测。结果 通过热老化试验,发现氟醚橡胶在200℃以下能够长期维持较好的力学性能。试验温度在200℃以上,氟醚橡胶的力学性能出现明显退化趋势,并且在热空气与热油中的老化趋势不同。在220℃的热空气老化31 d后,氟醚橡胶的拉伸强度下降27.0%,断裂伸长率增大89.8%,压缩应力松弛率为34.6%,硬度下降8.7%。在220℃的热油老化31 d后,氟醚橡胶的拉伸强度下降85.9%,断裂伸长率下降83.9%,压缩应力松弛率为-17.5%,硬度上升4.2%。结论 在热空气老化过程中,橡胶分子链受热氧影响发生断裂,使其强度下降;在热油老化过程中,油介质和高温的耦合作用使橡胶的交联网络失效,橡胶发硬变脆。     

橡胶工业废水深度处理回用的研究

采用混凝沉淀－砂滤,活性炭吸附和反渗透处理工艺,对齐鲁石橡胶厂排放的工业废水进行了深度处理后回用的实验研究。混凝沉淀－砂滤主要用于去除悬浮物质去除率约为９３％;活性炭主要去除难生物降解的可溶性有机物质对ＣＯＤ,石油类,挥发酚和色度的去除率分别为６０％,８０％,８０％和７０％;反渗透主要去除无机盐类和一些残余有机物质对ＴＤＳ和无机盐的去除率分别为９３％和８５％。     

橡胶厂污水达标排放改造

通过对橡胶厂污水处理系统各单元运行状况进行检测 ,找出系统不能达标排放的原因 ,提出了改造方案 ,并对系统进行了改造。改造后的结果表明 ,在来水处于正常的情况下 ,即CODCr<80 0mg L ,系统最终出水CODCr<10 0mg L。     

利用废旧橡胶研制管式微孔曝气器

采用废旧橡胶研制的微孔曝气器 ,制造工艺简单 ,机械强度高 ,价格低廉 ;传质效率高 ,曝气充氧性能优良 ,搅拌能力强 ;沿管长具有很好的均匀布气性 ,输气曝气合二为一 ,安装方便 ;拓展了废旧橡胶的综合利用途径 ,以废治废 ,减少了废旧橡胶对环境的污染 ,是固体废气物综合利用的环保型高科技产品。     

Enzyme catalyzed biodiesel production from rubber seed oil containing high free fatty acid

Unrefined rubber seed oil contains high levels of free fatty acids and moisture, which make the conventional chemical catalyzed transesterification unsuitable. The method of enzyme catalyzed transesterification is well suited for biodiesel production from rubber seed oil as the enzymes are insensitive to the free fatty acids. In the present work, rubber seed oil was extracted from preserved rubber seed cake by mechanical means. The extraction process was designed and optimized through 2⁴ full factorial design. Extracted oil was subjected to enzymatic transesterification using four different lipases to identify the best one for the purpose. Transesterification process was optimized by considering three influencing variables for biodiesel production viz. methanol/oil molar ratio, catalyst concentration (% w/v) and solvent content (% v/v). A 2³ full factorial design was applied to design the experiments and optimize the biodiesel production. The interactive effects of the independent variables on biodiesel yield were analyzed and regression models were developed for each set of enzyme reactions. Among the four lipases, Thermomysis Lanugonosus Lipase was found to be the most suitable for the transesterification of rubber seed oil with a biodiesel conversion of 92.83% at a molar ratio of 4% and 5% (w/v) enzyme concentration in solvent free reaction medium.     

烤胶废料活性炭对含铬废水的处理能力

介绍了微波照射下氯化锌法制取烤胶废料活的方法,用该方法所制烤胶废料活性炭处理含废水的结果表明,烤胶废料活性炭具有吸附容量大,过滤速度快,操作控制方便等优点,活性炭对铬的吸附容量是市售一级粉末活性炭的１．８倍。     

膜萃取邻甲酚废水的传质特性研究

构造了卷绕式及管束式两种膜组件,采用均质硅橡胶膜,以氢氧化钠溶液为萃取液来萃取邻甲酚废水.通过考察邻甲酚初始浓度、两相流动状态、两相压差(△P)和温度等因素对传质过程的影响,研究了邻甲酚废水的膜萃取过程与机制.结果表明,初始质量浓度为21.93 g/L的邻甲酚废水很适合直接进行膜萃取;当△P<0.07 MPa时,总传质系数(Kov)随△P的增大而略有减小.当△P>0.07 MPa时,Kov随△P增大而显著增大,由实验数据拟合得到总的膜萃取传质模型.且该模型的实验值与理论值的相对误差在5%以内,满足工业设计要求.     

氧化亚铁硫杆菌的筛选、生长特性及其橡胶再生研究

从大西洋底死火山口土壤中筛选出一株硫杆菌,经16S rDNA鉴定为氧化亚铁硫杆菌。研究了初始底物Fe2+浓度,初始pH,接种量对其生长的影响,确定了其最佳的生长的条件:在30℃、170 r/min条件下,最适底物Fe2+浓度为9 g/L,最佳初始pH为2.5,最适接种量为10%(体积分数)。探讨了氧化亚铁硫杆菌对天然硫化橡胶的脱硫再生,橡胶的SEM分析、FTIR图谱及EDS图谱研究表明氧化亚铁硫杆菌对硫化胶粉的硫交联键有断裂或转化作用,脱硫率达52.6%,氧化亚铁硫杆菌对天然橡胶具有一定的再生作用。