2,2′-二苯甲酰氨基二苯基二硫化物脱硫废乳胶的研究

以2,2′-二苯甲酰氨基二苯基二硫化物(DBADPDS)作为再生剂在密炼机中对废乳胶(WLR)进行脱硫再生,研究环烷油、再生剂用量和脱硫温度对脱硫效果的影响,并探讨脱硫机理。结果表明:随着环烷油用量的增大,再生胶的交联密度减小,脱硫效果增强;添加再生剂DBADPDS可以增强脱硫效果,但再生剂DBADPDS用量过大时,其含有的硫在高温下能参与WLR分子链间的交联反应,导致再生胶的交联密度增大;脱硫温度高于140℃,橡胶很容易发生裂解,脱硫过程中温度控制在120℃左右比较适宜。     

3种微生物脱硫废乳胶及其填充天然橡胶的性能对比

分别利用鞘氨醇单胞菌、脂环酸芽孢杆菌和酵母菌对废乳胶（WLR）进行脱硫再生,考察脱硫过程中微生物的生长情况以及脱硫前后WLR溶胀性和交联密度的变化,并研究WLR和脱硫WLR（DWLR）用量对天然橡胶（NR）拉伸性能和交联密度的影响。结果表明：3种微生物中,鞘氨醇单胞菌脱硫的WLR溶胀指数较大,交联密度较小。随着WLR用量的增大,填充NR硫化胶的拉伸强度和交联密度逐渐减小,拉断伸长率逐渐增大。DWLR/NR硫化胶的拉伸性能明显优于WLR/NR硫化胶,且鞘氨醇单胞菌脱硫的DWLR/NR硫化胶的拉伸性能明显优于其他两种微生物脱硫的硫化胶。     

密炼机工艺对废胎胶粉脱硫效果的影响

研究了密炼机再生工艺对废旧轮胎胶粉再生效果的影响。对再生橡胶的交联密度、溶胶含量、门尼黏度、物理机械性能和动态力学性能进行了分析。结果表明,溶胶含量随着脱硫温度的升高而逐渐增大;交联密度随着脱硫温度的升高而逐渐降低;根据horikx理论分析表明高混脱硫再生工艺再生过程中化学键的断裂以交联键断裂为主。再生胶的焦烧时间(ts 1)和再硫化时间(t9 0)随着脱硫温度的升高均呈现逐渐增大的趋势,拉伸强度随脱硫温度的增加逐渐降低。随脱硫时间的增加,再生胶硫化胶的拉伸强度略有降低,拉断伸长率变化不大。     

用Haake流变仪再生和硫化的废旧丁基橡胶的性能

利用Haake流变仪的高温和剪切作用对废旧丁基橡胶(IIR)进行脱硫,考察了加工温度对再生胶脱硫程度、硫化再生胶力学性能的影响以及废旧IIR、再生胶和硫化再生胶的阻尼性能。结果表明,Haake流变仪能使废旧IIR达到脱硫的目的,当加工温度为200~320℃时,随着加工温度的提高,脱硫程度增大;与废旧IIR相比,再生IIR和硫化再生IIR的阻尼性能有很大程度提高。     

三种微生物脱硫废乳胶及其填充天然橡胶的力学性能比较

利用三种微生物鞘氨醇单胞菌、脂环酸芽孢杆菌和酵母菌对废乳胶(WLR)进行了脱硫再生,考察了脱硫过程中微生物的生长情况以及脱硫前后WLR溶胀和交联密度的变化,并将WLR和脱硫WLR(DWLR)以不同份数填充到天然橡胶(NR)中,对比了DWLR/NR硫化胶和WLR/NR硫化胶的力学性能和交联密度。结果表明,利用鞘氨醇单胞菌脱硫的WLR溶胀值较高,交联密度较低。随着乳胶用量的增加,填充NR硫化胶的拉伸强度和交联密度逐渐降低,扯断生长率逐渐增加。DWLR/NR硫化胶的力学性能明显优于WLR/NR硫化胶,且鞘氨醇单胞菌脱硫的DWLR/NR的力学性能明显优于其它两种微生物脱硫的DWLR/NR硫化胶。     

转矩流变仪制备再生胶的工艺及性能

利用转矩流变仪的高温剪切作用并添加再生活化剂420对废旧轮胎胶粉(GTRP)进行了再生,讨论了活化剂用量和加工温度对再生胶再生程度及力学性能的影响。结果表明,随着活化剂用量的增大和温度的上升,GTRP溶胶含量明显上升,门尼粘度和交联密度均明显下降。转子转速为50r/min,加工时间为15min,加工温度为170℃,活化剂420用量为0.5份时,所得再生胶具有最佳综合力学性能。     

微波脱硫制备三元乙丙橡胶再生胶的结构和性能研究

研究微波脱硫对三元乙丙橡胶再生胶结构和性能的影响。结果表明：脱硫效果随脱硫温度的上升而越来越明显,当脱硫温度达到280 ℃左右时脱硫效果较好;脱硫16 min左右的再生胶物理性能较好;再生胶共混填充的最佳用量为20份。     

塑解剂二苯甲酰胺基二苯基二硫化物与有机酸并用对废旧胶粉再生效果的影响

以化学塑解剂二苯甲酰胺基二苯基二硫化物(DBD)为再生活化剂,将其与有机酸并用对废旧胶粉进行再生,考察了4种芳香酸(苯甲酸、水杨酸、硫代水杨酸、二硫代二苯甲酸)和5种脂肪酸(己二酸、草酸、酒石酸、苹果酸、硬脂酸)对再生胶性能的影响。结果表明,4种芳香酸的加入均可使再生胶的溶胶含量增加,交联密度和门尼黏度降低,且再生胶的拉伸强度略有降低,扯断伸长率提高,邵尔A硬度略有下降,其中二硫代二苯甲酸的辅助再生效果较好,且其用量的增加可改善再生效果; 5种脂肪酸的加入均可使再生胶的溶胶含量增加,交联密度和门尼黏度降低,且再生胶的拉伸强度提高,不利于改善扯断伸长率,邵尔A硬度变化不大,其中酒石酸和硬脂酸的辅助再生效果较好,且其用量的增加可改善再生效果。     

高温高压动态脱硫罐结构的探讨

高温高压动态脱硫法是国外70年代、国内80年代末期出现的橡胶再生新工艺,其特点,一是脱硫温度可高达220℃,二是再生(脱硫)过程中物料始终处于运动状态。 该工艺在国内虽处于发展的初期,但其脱硫质量与节能降耗是目前国内所有再生方法无法比拟的。脱硫物判直径较大,脱硫时间短,无污水排放,产品质量达到水油法水平。从目前再生胶生产的趋势来看,脱硫时胶粉的粒径不是向细的方向发展,而是向粗的方向发展,籍此大幅度降低能耗。再生胶产品质量是用     

采用微波脱硫罐制备三元乙丙橡胶再生胶

采用自制微波脱硫罐对三元乙丙橡胶(EPDM)胶粉进行微波脱硫制备EPDM再生胶,并研究搅拌速度和脱硫温度等对EPDM再生胶性能的影响。结果表明:搅拌速度对EPDM胶粉的脱硫均匀性有影响,但对EPDM再生胶的物理性能影响不大;脱硫温度对EPDM胶粉的脱硫效果影响很大;当脱硫功率为2 k W、胶粉填充量为5 kg、搅拌速率为60r·min-1、脱硫温度为270℃左右时,EPDM再生胶物理性能较佳。     

变换气脱硫技术综述

介绍了栲胶法、MSQ法、PDS法和DDS法变换气脱硫工艺。对变换气脱硫技术的进展情况进行了综述     

Simultaneous Removal of NO and SO2 from Flue Gas by UV/H2O2/CaO

The effects of several influencing factors (CaO and H₂O₂ concentration, gas flow, solution temperature, NO, SO₂, O₂ and CO₂ concentration) on the simultaneous removal of NO and SO₂ from flue gas by using a UV/H₂O₂/CaO process were studied. In addition, the anions in the liquid phase were measured by ion chromatography and the material balances for NO and SO₂ were calculated. It was found that, under all experimental conditions, this process achieved a SO₂ removal efficiency of 100 %. With the increase in CaO concentration, NO removal efficiency first increased and then remained almost unchanged. With the increase in H₂O₂ concentration, NO removal efficiency increased but the changes gradually became smaller. NO removal efficiency greatly decreased with increasing gas flow, NO concentration and CO₂ concentration. Slightly increasing the solution temperature and SO₂ concentration reduced NO removal efficiency. Increasing O₂ concentration can promote the removal of NO. The anions in the liquid phase were mainly SO₄^2– and NO₃^–. Most of the low valence nitrogen elements in NO and the low valence sulfur elements in SO₂ transformed into the high valence nitrogen element in NO₃^– and the high sulfur element in SO₄^2–.     

A comparative study on H2S removal using Mg-Al spinel (MgAl2O4) and MgO/Al2O3 nanocomposites

In this work MgO/Al2O3 nanocomposites with weight ratios from 5％ to 25％ were synthesized by precipitation-impregnation method and their structural properties were characterized.In the next step,the capability of the nanocomposites in H2S removal compared to Mg-Al spinel (MgAl2O4),synthesized through ion-pair complex precursor route and alumina samples,prepared via sol-gel precipitation methods,was investigated.The results indicated that among the studied sorbents Mg-Al spinel presents a distinctly higher H2S removal.In addition,the MgO/Al2O3 nanocomposites compared to the alumina sorbents,exhibited much better performance in H2S removal.Also CO2-TPD analysis reveals higher amounts of basic sites for Mg-Al spinel compared to 25 wt％ MgO/75 wt％ Al2O3 nanocomposite.     

浸渍活性炭脱除H2S的反应动力学

提出了浸渍活性炭脱除Ｈ２Ｓ的反应过程机理模型，认为脱硫过程主要是Ｈ２Ｓ在活性炭的吸附水膜内离解后被活化的Ｏ２分子以及活性氧原子氧化生成单质硫逐渐沉积在活性炭表面，同时应用最小二乘法回归实验数据得到了脱硫动力学方程ｄＷｓ／ｄｔ＝ｋ１ｋ２／ａｐｏ２／ｐＨ２Ｓ／１＋ｋ２ｐｏ２×（１－αＷｓ）＾２其中动力学参数ｋ１＝３．７５３×１０＾５ｅｘｐ「－３００６．５／Ｔｒ」ｋ２／０．２６３ｅｘｐ「１９４５．６／Ｔ     

Mesoporous Ag2O/ZrO2 heterostructures as efficient photocatalyst for acceleration photocatalytic oxidative desulfurization of thiophene

The production of fuels with a low sulfur content has been paid significant attention in the manufacturing of petroleum refining due to the progressively severe environmental legislations obliged by governments worldwide. In this paper, for the first time, two dimensional mesoporous Ag₂O/ZrO₂ heterostructures were synthesized by a facile approach for thiophene photocatalytic oxidative desulfurization under visible-light exposure at room temperature. The Ag₂O/ZrO₂ heterostructures significantly enhanced the photocatalytic desulfurization of thiophene obeyed the pseudo-first-order model compared to pristine ZrO₂ NPs. In particular, 1.5%Ag₂O/ZrO₂ photocatalyst exhibited better photocatalytic performance and the correspondent rate constant of 0.0235 min^?1, which was promoted 5.35 times than that of pristine ZrO₂ NPs (0.0044 min^?1). The desulfurization rate of thiophene over 1.5% Ag₂O/ZrO₂ heterostructure was enhanced 3.7 times larger than that of pristine ZrO₂ NPs. The thiophene was photocatalytically oxidized to CO₂ and SO₃. The photocatalytic performance of Ag₂O/ZrO₂ could be enhanced because of its synergetic effects, the intense visible-light harvest, rapid mobility of the thiophene to the active sites, a lower light scattering effect, and a large ^?OH radical contents formed. Moreover, the Ag₂O/ZrO₂ heterostructures revealed excellent stability toward the photocatalytic oxidative desulfurization of thiophene. A possible charge separation mechanism over mesoporous Ag₂O/ZrO₂ heterostructures was proposed.     

国外络合铁法脱硫技术研究进展

综述了国外络合铁法脱硫技术的现状和发展趋势 ,介绍了LO -CAT和SulFerox两种络合铁脱硫工艺 ,并对该工艺进行了经济分析     

真空碳酸钾法脱硫废液中S_2O_3~(2-)和SCN-的测定

通过碘量法和分光光度法分别测定了脱硫废液中S2O2-3与SCN-的含量,并排除了实验中的干扰因素,S2O2-3、SCN-的质量浓度分别为15 989.1mg/L、7 543.0mg/L,误差分析后,S2O2-3的标准偏差为2.7~6.9,相对标准偏差为1.7%~2.3%,回收率为99.8%~100.2%;SCN-的标准偏差为4.06~11.68,相对标准偏差为5.4%~6.3%,回收率为99.5%~103.8%。     

Dry gas cleaning process by adsorption of H2S into activated cokes in gasification of carbon resources

Gasification of carbon resources including biomass and coal is one of promising energy production technologies. The R&D on effective and convenient gas cleaning processes for removal of contaminants as well as high efficient reliable gasifiers is essential for industrial application in broad fields. In this study, a dry process of synthesis gas cleaning by adsorption of H₂S into activated cokes was proposed as a candidate of desulfurization technologies in gasification. The H₂S adsorption performance of activated coke produced from coal, which are used industrially for de-SO_x and de-NO_x, was evaluated by the thermogravimetric analyses and the adsorption examination in a fixed bed under the atmospheric and high pressures. Activated coke was not only the most active at about 423 K for the H₂S adsorption rate but also regenerative over 573 K by H₂S desorption with a sufficient rate under an inert gas flow of nitrogen. The H₂S adsorption performance of the activated coke was not inhibited by the co-existence of CO₂ or COS but enhanced rather by the co-existence. The adsorbent was promisingly active for both H₂S and COS adsorption as well. These behaviors suggest that the activated coke are available for simultaneous desulfurization of H₂S and COS. The H₂S breakthrough examination in the fixed bed revealed that it was possible to remove H₂S to lower level than 1 ppm for a long time depending on the residence time of gas flow in the bed. When the adsorption operation was carried out under high pressures up to 0.6 MPa, the regeneration of activated coke by H₂S desorption took place under the pressure reduced to the atmosphere. As the results, it was implied that the present activated coke could be applicable to the desulfurization process in coal gasification.     

Photocatalytic desulfurization of thiophene under visible light by hollow flower-like NixZn2-xV2O7/WO4 nanostructures

In order to improve the desulfurization efficiency of petroleum derivatives, this paper reports the synthesis and characterization of hollow flower-like Ni_xZn_2-xV₂O₇/WO₄ nanostructures through a simple Pechini sol-gel method. The type of chelating agent, gelling agent, and elements ratio were investigated as factors affecting morphology to determine the optimal conditions. SEM images showed that if all the elements Ni, Zn, V, and W were involved in the formation of the product, hollow flower-like nanostructures with a high surface area were formed while in the absence of any of these elements the morphology changed. Good morphology and high adsorption efficiency along with ultra-light absorption according to DRS, resulted in more than 95% efficiency of photocatalytic oxidative desulfurization after 2.5 hours under visible light. The reduction in efficiency from 95% to 23% in the presence of EDTA indicated that superoxide was the most active radical species in the process. Comparison of the performance of Zn₂V₂O₇/ZnWO₄, Ni₂V₂O₇/NiWO₄, NiZnWO₄, and NiZnV₂O₇, which were 66%, 69%, 84% and 63%, respectively, showed the effect of the type of composition in addition to morphology.     

Oxidative desulfurization of tire pyrolysis naphtha in formic acid/H2O2/pyrolysis char system

Waste tires are one potential source of alternative energy because of their long chain hydrocarbon with a high calorific heating value. However, the pyrolysis oil that is derived from waste tires is not appropriate for direct use in a combustion process due to its high sulfur content. Therefore, the oxidative desulfurization (ODS) process was evaluated for its ability to reduce the sulfur content of the naphtha fraction distillated from light oil derived from waste tire pyrolysis. The addition of formic acid to pH of 4.0 in the presence of 25 vol.% hydrogen peroxide (H₂O₂) and tire pyrolysis char enhanced the level of sulfur removal to ca. 70% due to the simultaneous adsorption and oxidation of sulfurous compounds on the surface of the pyrolysis char. The chemical treatment to form surface-modified char promoted the benefit for ODS process in the presence of formic acid (pH 4) and H₂O₂ (25 vol.%) by increasing the sulfur reduction in the pyrolysis naphtha up to 75%.