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1.
A novel bioactive foam emulsion bioreactor for benzene, toluene and xylene (BTX) contaminated air streams treatment has been developed. The gas-liquid interfacial area by biocompatible foam and driving force for mass transfer by a water immiscible organic phase were increased in this reactor. The effect of several parameters such as gas residence time, oxygen content, and organic phase concentration on bioreactor performance was studied. Experimental results showed an average elimination capacity (EC) of 220 g&;#8226;m-3&;#8226;h-1 with removal efficiency (RE) of 89.59% for BTX inlet concentration of 1 g&;#8226;m-3 at 15 s gas residence time in the bioreactor. The statistical developed model predicted that the maximum elimination capacity of the reactor for BTX could be reached to 423.45 g&;#8226;m-3&;#8226;h-1. Continues operation of the bioreactor with high EC and RE was demonstrated by optimizing the operational parameters of the bioreactor. Overall the results suggest that the bioreactor developed can be very effective systems to treat BTX vapors.  相似文献   

2.
Amine-functionalized mesoporous silica was prepared by using lauric acid and N-stearoyl-l-glutamic acid as structure directing agents via the SN+-I mechanism and applied to CO2 adsorption at room temperature. With γ-aminopropyltriethoxysilane as co-structure directing agent and due to the direct electrostatic interaction with anionic surfactant, most of the amino groups were uniformly distributed at the inner surface of pores and the performance was stable. The amine-functionalized mesoporous silica was characterized by Fourier transform infrared spectrometer, X-ray diffraction, nitrogen physisorption and thermogravimetric analysis. The CO2 adsorption capacity was measured by digital recording balance. At the room temperature and under the atmospheric pres-sure, the adsorption capacity of LAA-AMS-0.2 for CO2 and N2 is 1.40 mmol•g1 and 0.03 mmol•g1, respectively, indicating high separation coefficient of CO2/N2.  相似文献   

3.
Additives were used to increase gas hydrate formation rate and storage capacity. Experimental tests of methane hydrate formation were carried out in surfactant water solutions in a high-pressure cell. Sodium dodecyl sulfate (SDS) and alkyl polysaccharide glycoside (APG) were used to increase hydrate formation. The effect of SDS on hydrate formation is more pronounced compared APG. Cyclopentane (CP) also improves hydrate formation rates while it cannot increase methane gas storage capacity.  相似文献   

4.
The biodegradations of phenol and 4-chlorophenol (4-cp) were studied using the mutant strain CTM 2 obtained by the He-Ne laser irradiation on wild-type Candida tropicalis. The results showed that the capacity of the CTM 2 to biodegrade 4-cp was increased up to 400 mg•L-1 within 59.5 h. In the dual-substrate biodegradation, both velocity and capacity of the CTM 2 to degrade 4-cp increased with low-concentration phenol. A total of 400 mg•L-1 4-cp was completely degraded within 50.5 h in the presence of 300 mg•L-1 phenol. The maximum 4-cp biodegradation could reach 440 mg•L-1 with 120 mg•L-1 phenol. Low-concentration 4-cp caused great inhibition on the CTM 2 to degrade phenol. In addition, the kinetic behaviors were described using the kinetic model proposed in this lab.  相似文献   

5.
The CuO/γ-Al2O3/cordierite catalyst, after being sulfated by sulfur dioxide (SO2) at 673 K, exhibits high activities for selective catalytic reduction (SCR) of nitrogen oxide (NO) with ammonia (NH3) at 573-723 K. The intrinsic kinetics of SCR of NO with NH3 over CuO/γ-Al2O3/cordierite catalyst has been measured in a fixed-bed reactor in the absence of internal and external diffusions. The experimental results show that the reaction rate can be quantified by a first-order expression with activation energy of 94.01 kJ•mol1 and the corresponding pre-exponential factor of 3.39×108 cm3•g1•s1 when NH3 is excessive. However, when NH3 is not enough, an Eley-Rideal kinetic model based on experimental data is derived with Ea of 105.79 kJ•mol1, the corresponding A of 2.94×109 cm3•g1•s1, heat of adsorption ΔHads of 87.90 kJ•mol1 and the corresponding Aads of 9.24 cm3•mol1. The intrinsic kinetic model obtained was incorporated in a 3D mathematical model of monolithic reactor, and the agreement of the prediction with experimental data indicates that the present kinetic model is adequate for the reactor design and engineering scale-up.  相似文献   

6.
Considering limited success in target-hitting discharge from alcohol industry, our attention was directed toward a recycling use of distillery spentwash (DS) in cassava bioethanol production by using a two-stage up-flow anaerobic sludge blanket bioremediation (TS-UASBB). With the TS-UASBB, , COD, N and P in the effluent from the DS degraded significantly and their concentrations were kept at 0.2 g•L1, 2.0 g•L1, 1.0 g•L1 and 15 mg•L1, respectively, in 13 batch processes for water-recycled ethanol fermentation. With the effluent used directly as dilution water, no heat-resistant bacteria were found alive. The thirteen-batch ethanol production individually achieved 10% after 48 h fermentation. The starch utilization ratio and total sugar consumption were 90% and 99.5%, respectively. The novel water-recycled bioethanol production process with ethanol fermentation and TS-UASBB has a considerable potential in other starchy and cellulosic ethanol production.  相似文献   

7.
A strain isolated from the fruiting body of a fungus parasitized on Elaphomyces was identified as Cordyceps ophioglossoides based on the morphological characteristics and the analysis of ITS-5.8s rDNA sequence. The optimal medium composition (g•L-1), containing sucrose 66.0, yeast powder 10.0, silkworm chrysalises digest 30.0, MgSO4•7H2O 0.4, and KH2PO4 0.4, was found using fractional factorial design and a central composite design, and the optimization of cultural conditions obtained a result of seed age 6 days, inoculum size 6% (by volume), initial pH 5.6, temperature 24°C, shaking speed 160 r•min-1 by one-factor-at-a-time method. The maximum biomass reached about 20.2 g•L-1 after 90 hours culture under the optimal conditions. Elementary pharmacological activities showed that mycelia of C. ophioglossoides L2 from submerged culture promoted uterus growth in estrogen- depleted mice. In the 15-litre scale-up fermentation, the mycelial biomass was around 19.1 g•L-1, indicating a promising prospect for this biotechnology and the potency to develop its medical value.  相似文献   

8.
Supercritical CO2 (SC-CO2) extraction technology and ultrasonic technology were used to extract two active sex hormones, estradiol and progesterone, and insulin-like growth factor-1 (IGF-1) from antler velvet. The effects of SC-CO2 extraction condition on the extraction yield and content of sex hormones, the ultrasonic extraction condition on the content of IGF-1 and the SC-CO2 extraction condition on the activity remaining of IGF-1 were studied. The optimal conditions were obtained. The experimental results showed that, in presence of 75% ethanol as the co-solvent, the mean yield and content of estradiol and progesterone were 87.67 pg•g-1 and 1224.10 pg•g-1, 12.38 ng•g-1 and 354.06 ng•g-1, respectively, with extraction pressure of 30 MPa, temperature of 35°C, extraction time of 30 min and CO2 consumption of 15 L•g-1 at the flow rate of 2.0 L•min-1. The highest content of IGF-1 was 7425.75 ng•g-1 antler velvet residue, when the pH10 ammonia-ammonium chloride buffer solution was used as the solvent, the ratio of solvent to sample was 20/1 (volume/mass), the extraction temperature was 0-35°C, and the ex-traction time was 4×15 min. Under these conditions, 93.68% activity remaining of IGF-1 in the residue was ob-tained, while little IGF-1 activity exists in traditional residue. The experimental results indicate that the technology of SC-CO2 with co-solvent is of advantage for getting high content sexual hormones and keeping high activity of IGF-1 in the residue, which can not be achieved by traditional extraction methods.  相似文献   

9.
Baker’s yeast number 6 was selected by screening. It showed good catalytic activity and enantioselectivity for asymmetric reduction of 2,5-hexanedione to produce (2S,5S)-2,5-hexanediol. Gas chromatography-mass spectrometry (GC-MS) revealed that the intermediate was (S)-5-hydroxyhexane-2-one. Reduction of 2,5-hexanedione proceeded in a two-step reaction. The hydroxyketone was initially formed, and this intermediate was further re-duced to the diol. Factors influencing the product yield and the enantiomeric excess of the reduction of 2,5-hexandione catalyzed by baker’s yeast number 6 were investigated. Higher concentration (≤100 mmol•L-1) of 2,5-hexandione did not influence 5-hydroxyhexane-2-one production, but 2,5-hexanediol production was inhibited by excess accumulation (>30 mmol•L-1) of intermediate. The optimal conditions were glucose as the co-substrate at an initial glucose concentration of 20 g•L-1, 34C, pH 7.0 and cell concentration 60 g•L-1 (cell dry mass). Under the optimal condition and an initial substrate concentration of 30 mmol•L-1, the yield of 2,5-hexandiol was 78.7% and the enantiomeric excess of (2S,5S)-2,5-hexandiol was 94.4% for 24-h reduction.  相似文献   

10.
The adsorption equilibrium of a fluoride solution on 1-2 mm granular activated alumina modified by Fe2(SO4)3 solution was investigated. The experiments were conducted using a wide range of initial fluoride concentrations (0.5 to 180 mg•L1 at pH ~7.0) and an adsorbent dose of 1.0 g•L1. The application of Langmuir and Freundlich adsorption isotherm models (linear and nonlinear forms) generally showed that a single Langmuir or Freundlich equation cannot fit the entire concentration gap. Experimental data on low equilibrium concentrations (0.1 to 5.0 mg•L1) was in line with both Langmuir and Freundlich isotherm models, whereas that of high equilibrium concentrations (5.0 to 150 mg•L1) was more in line with the Freundlich isotherm model. A new Langmuir- Freundlich function was used for the entire concentration gap, as well as for low and high concentrations.  相似文献   

11.
胡慧慧  杨亮  刘道平  张柯 《化工学报》2022,73(10):4659-4667
高储气密度水合物的快速生成对气体水合物技术应用至关重要。将水与疏水性气相纳米二氧化硅和低剂量[0.1%~1.0%(质量)]的超吸水树脂在搅拌器中高速混合分散,制备出一种超吸水树脂改性的干水。该改性干水实质上是由高分子聚合物支撑且可自由流动的分散微滴堆。在8.0 MPa和274.2 K条件下,研究该改性微滴中甲烷水合物生成动力学特性。结果表明,松散的聚合物微滴极大地改善了液相连续水比表面积,为气体扩散至微滴表面提供了丰富的通道。水合物在聚合物微滴中快速生成,储气速率可达5.15~8.78 cm3·g-1·min-1,储气量高达158.0~175.0 cm3·g-1。质量分数为0.3%的微滴表现出最快储存速率和最高储气量,且其循环水合储气过程中前6次储气量均超过120 cm3·g-1。研究结果对水合物储运天然气技术规模化应用有一定的参考价值。  相似文献   

12.
胡慧慧  杨亮  刘道平  张柯 《化工学报》1951,73(10):4659-4667
高储气密度水合物的快速生成对气体水合物技术应用至关重要。将水与疏水性气相纳米二氧化硅和低剂量[0.1%~1.0%(质量)]的超吸水树脂在搅拌器中高速混合分散,制备出一种超吸水树脂改性的干水。该改性干水实质上是由高分子聚合物支撑且可自由流动的分散微滴堆。在8.0 MPa和274.2 K条件下,研究该改性微滴中甲烷水合物生成动力学特性。结果表明,松散的聚合物微滴极大地改善了液相连续水比表面积,为气体扩散至微滴表面提供了丰富的通道。水合物在聚合物微滴中快速生成,储气速率可达5.15~8.78 cm3·g-1·min-1,储气量高达158.0~175.0 cm3·g-1。质量分数为0.3%的微滴表现出最快储存速率和最高储气量,且其循环水合储气过程中前6次储气量均超过120 cm3·g-1。研究结果对水合物储运天然气技术规模化应用有一定的参考价值。  相似文献   

13.
裴俊华  杨亮  汪鑫  胡晗  刘道平 《化工学报》2021,72(11):5751-5760
提高水合物生成速率和储气密度对天然气水合物技术应用非常重要。将三种孔密度的泡沫铜(CF)分别浸入十二烷基硫酸钠(SDS)溶液中构建水合储气强化体系,在高压静态反应釜中研究泡沫金属对甲烷水合物生成动力学特性。实验结果表明,泡沫铜骨架能为水合物生成提供充足的结晶点,同时可作为水合物生长过程水合热迁移的“高速公路”。甲烷水合物在SDS/CF体系中可快速生成,最大水合储气速率分布在19.24~21.04 mmol·mol-1·min-1之间,其中添加15 PPI泡沫铜的SDS溶液储气量最高(139 mmol·mol-1),且达到最大储气量90%所用时间最短(10.1 min)。在6.0~8.0 MPa压力下,相比SDS溶液,添加15 PPI泡沫铜的SDS溶液储气量提高了8.8%~35.6%,储气速率提高了4.7%~40.4%;特别在压力为5.0 MPa时,该孔密度SDS/CF体系储气量甚至比SDS溶液增加13倍,储气速率增加16倍。  相似文献   

14.
Time‐dependent isochoric formation of methane hydrate was investigated in the presence of low‐dose poly(ethylene oxides) (PEOs). The effect of different molecular weights of PEO on methane hydrate nucleation time and storage capacity was studied and compared. Kinetic measurements revealed a dual effect of PEO, including inhibition and stabilization effects, on methane hydrate formation. The nature and type of the effect arises from the difference in molecular weights and concentration ranges of PEOs. These parameters directly affect the nucleation time and storage capacity of methane hydrate. Generally, in comparison with pure water, PEO improved the storage capacity of methane hydrate. PEO (1000 kD) at a concentration of 0.5 wt % exhibits a significant kinetic inhibitory performance. However, it was an efficient low‐dosage hydrate stabilizer at a concentration of 0.25 wt %, along with producing gas‐rich methane hydrate suitable for gas fuel storage and transportation.  相似文献   

15.
王燕鸿  姚凯  郎雪梅  樊栓狮 《化工学报》2021,72(9):4872-4880
油包水乳液是近年来新兴的一种水合强化材料,具有良好的水合储气潜力,但是为了保证乳液的稳定性,通常所用的油包水乳液含水量不超过50%。然而水合物的储气量与水含量密切相关,因此高含水的油包水乳液更具有应用前景。对含水量超过50%的油包水乳液进行了水合物的储甲烷研究,考察了乳化剂用量、初始压力及搅拌速率对储气性能的影响,最后考察了乳液的循环储气能力。结果表明:含水量超过55%后,含水量的增加会造成乳液液滴的增大,储气量的降低。乳液含水量为55%,复合乳化剂Span80 / Tween80(mTween80mSpan80=0.783∶1)用量5%(质量)(以水量为基准)的乳液最适合水合储气;初始压力的增加有利于水合储气性能的提高,但压力过高会造成水合物壳的快速形成,从而降低整体储气能力;适宜的搅拌速率有利于水合物的生成,过快或过慢都会引起水合速率的下降。本实验中最佳的乳液水合储气条件为:温度274.15 K、反应釜中气水体积比10∶1、甲烷初始压力6 MPa、搅拌速率700 r/min,在此条件下,储气量可达141.42 L 气/L 水。在此条件下进行循环储气实验证明该乳液具有良好的循环利用性,四次循环中储气量均在130 L 气/L 水以上。研究结果可为天然气储运以及含烃混合气分离提供技术参考。  相似文献   

16.
In this communication, the kinetic parameters of methane hydrate formation (induction time, quantity and rate of gas uptake, storage capacity (SC), and apparent rate constant) in the presence of sodium dodecyl sulfate (SDS), synthetized silver nanoparticles (SNPs), and mixture of SDS?+?SNPs have been studied. Experimental measurements were performed at temperature of 273.65?K and initial pressure of 7?MPa in a 460?cm3 stirred batch reactor. Our results show that adding SDS, SNPs and their mixture increases the quantity of gas uptake, water to hydrate conversion, and SC of methane hydrate formation, noticeably. Using 300?ppm SDS increases the SC and the quantity of methane uptake 615, and 770%, respectively, compared with pure water. Investigating the hydrate growth rate at the start of hydrate formation process shows that, using SNPs, SDS, and their mixture increases the initial apparent rate constant of hydrate rate, considerably. Our results show that the system of methane?+?water?+?SDS 500?ppm?+?SNPs 45?µM represents the maximum value of initial apparent rate constant, compared with other tested systems.  相似文献   

17.
邱传宝 《广东化工》2012,(12):77-78,92
利用搅拌器通过高速剪切的方法制备了疏水性气相二氧化硅(HB-630):结冷胶:水的质量比为1:2:17的凝胶干水,用显微镜观察了其微观形貌,并用高压水合物反应装置对其进行了储甲烷实验研究。显微观察发现,凝胶干水粒径范围为10~150(?)m。储甲烷实验表明,在压力为7.98 MPa、温度为0.8℃左右甲烷能在6 min内与凝胶干水作用快速生成水合物,并且2 h内储甲烷量达到100(V/V),大大提高了水合物储甲烷速率和短时间内的储气量。通过5次循环储甲烷实验发现,凝胶干水储甲烷量随着循环次数的增加而降低。  相似文献   

18.
处理低浓度氨氮废水吸附材料的筛选   总被引:8,自引:2,他引:6       下载免费PDF全文
目前吸附材料种类繁多,给处理低浓度氨氮废水的选型带来一定困难。依据离子交换理论,研究了用沸石、氧化铝和煤渣处理浓度为50 mg.L-1模拟氨氮废水的效果,并绘制了吸附等温线,测定这3种吸附材料对氨氮废水的离子交换速率及不同pH值和不同温度下交换容量的影响,并通过工业氨氮废水检验处理效果。结果表明,沸石和氧化铝满足Langmuir吸附等温模式,而煤渣满足Freundlich吸附等温式,三者的最大吸附量分别为8.29、1.69和2.16 mg.g-1;以沸石处理低浓度氨氮废水效果最好,反应速率快,适应条件宽,是处理低浓度氨氮废水的良好吸附材料。  相似文献   

19.
表面活性剂吸附对促进甲烷水合物生成效果的影响   总被引:1,自引:1,他引:0       下载免费PDF全文
基于表面活性剂固-液界面吸附理论,在无搅拌条件下研究了十二烷基硫酸钠(SDS(、脂肪醇聚乙烯醚硫酸钠(AES(、脂肪醇聚乙烯醚(AEO(3种表面活性剂在不锈钢反应釜中对甲烷水合物生成的促进效果。结果表明:水合物的生成形态与表面活性剂吸附金属表面形态有良好的对应关系;SDS与AES在金属表面的吸附作用可使水合物成核速率提高,成核位置增多。由于AEO不能在金属壁面发生吸附,导致对水合物生成促进效果降低,在浓度为300 mg·L-1的SDS、AES和AEO溶液中,水合物储气密度及平均储气速率分别为131.4、128.3、12.3(体积比(和5.8、7.6、0.07 mmol·min-1;逐步提高SDS溶液浓度(80~1200 mg·L-1(和AES溶液浓度(60~1350 mg·L-1(,水合物储气密度首先增大然后减小,储气速率线性增大。因此,合理选择表面活性剂种类及浓度,可显著促进水合物生成。  相似文献   

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