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121.
根据生产实际,对装置控制方案进行优化,减少外界蒸汽压力波动对装置的影响,保证共沸蒸馏塔和甲醇回收塔的灵敏板温度稳定,塔顶和塔底产品合格;在线近红外光谱醇烯比分析及闭环控制系统投用后,提高了MTBE产量,降低了甲醇、C4和蒸汽单耗。 相似文献
122.
123.
A thorough understanding of bacteria transport in soil and groundwater is vital to the successful practice of environmental bioremediation.In this work,a dual-process adsorption with growth and decay model of bacterial transport was proposed.The onsite soil and the high efficiency methyl tertbutyl ether (MTBE) degrading bacterium Chryseobacterium sp.A-3,was used in the experiments.The model was validated using one-dimensional soil column experiments.The results show that the dual-process adsorption with growth and decay model proposed well describes the migration mechanism of microorganisms in soil and groundwater environment.According to the model analysis and simulation,the bacterial transport is enhanced as flow velocity and inlet cell concentration increase.Compared with the contaminant MTBE,the bacteria show stronger transport capacity but the irreversible straining in soil prevents the bacteria from transporting longer than MTBE.The results have certain instructive significance to the insitu contamination remediation operation. 相似文献
124.
对柴油-乙醇-MTBE混合燃料的物理化学性质、经济性、排放性和燃烧特性进行了研究.通过对三种配比(90%柴油 10%MTBE,85%柴油 10%MTBE 5%乙醇,80%柴油 10%MTBE 10%乙醇)的混合燃料的冷凝点、馏程、溶解曲线、负荷特性、烟度排放和示功图的测试和研究,总结出了添加MTBE和乙醇后,混合燃料的物化性质、经济性、排放性、燃烧特性的变化规律. 相似文献
125.
针对MTBE装置萃取塔填料环堵塞问题,从工艺操作、原料性质等方面进行了探讨,并总结了萃取塔填料环清洗方法和预防堵塞措施. 相似文献
126.
Sorption and pervaporation experiments were carried outwith PVA/PAA cross-linked membranes for the separation of azeotropic methyl tert-butyl ether and methanol mixtures. The influence of the PVA/PAA ratio and liquid mixture composition were investigated. With increasing PAA content in the membranes, solubilities and fluxes decreased and selectivities increased. Total sorption and fluxes increased with increasing concentration of McOH. Increasing the concentration of McOH resulted in decreasing selectivities. Because of polarity, McOH permeated selectively through the membranes. Sorption results showed the same tendency with pervaporation results. 相似文献
127.
MTBE裂解制异丁烯技术进展 总被引:1,自引:0,他引:1
论述了MTBE裂解制异丁烯所用催化剂的研究进展,介绍了工艺过程及有关的技术。 相似文献
128.
Triflic acid loaded Y-type zeolite appears to be as active as the Amberlysi 15 in the (gas phase) synthesis of MTBE. However, the zeolite catalyst produces less by-products and is more thermally stable than the resin based catalyst.Presented at the 11th Canadian Symposium on Catalysis, Halifax (Canada), July 15 to 18, 1990. 相似文献
129.
Fenton-driven chemical regeneration of MTBE-spent GAC 总被引:1,自引:0,他引:1
Methyl tert-butyl ether (MTBE)-spent granular activated carbon (GAC) was chemically regenerated utilizing the Fenton mechanism. Two successive GAC regeneration cycles were performed involving iterative adsorption and oxidation processes: MTBE was adsorbed to the GAC, oxidized, re-adsorbed, oxidized, and finally re-adsorbed. Oxidant solutions comprised of hydrogen peroxide (H2O2) (1.7-2.0%) and FeSO4 x 7H2O (3 g/L) (pH 2.5), were recirculated through the GAC column (30% bed expansion). The regeneration efficiency after two full cycles of treatment was calculated to be 91%. The cost of H2O2 was 0.59 dollars/kg GAC (0.27 dollars/lb) per regeneration cycle. There was no loss of sorptive capacity. Small reductions in carbon surface area and pore volume were measured. The lack of carbon deterioration under aggressive oxidative conditions was attributed to the oxidation of the target contaminants relative to the oxidation of carbon surfaces. The reaction byproducts from MTBE oxidation, tertiary butanol and acetone, were also degraded and did not accumulate significantly on the GAC. Excessive accumulation of Fe on the GAC and consequent interference with MTBE sorption and carbon regeneration was controlled by monitoring and adjusting Fe in the oxidative solution. 相似文献
130.
Photodegradation of methyl tertiary butyl ether (MTBE) vapor with immobilized titanium dioxide 总被引:1,自引:0,他引:1
A study on the photocatalytic degradation of methyl tertiary butyl ether (MTBE) vapor was performed with respect to reaction parameters, kinetics, and mechanism. A conventional TiO2-coated plate system was used for this initial work on vaporized MTBE. On irradiating with UVBLB (5 mW/cm2), 0.6 mg/cm2 of TiO2 (P25) photocatalyst showed the highest reaction rate (0.85 μmol/min) for 25.76 μmole of MTBE (1000 ppmv). The numerical values obtained depended predictably with respect to light intensity, initial concentration, and quantity of P25. The photocatalytic degradation of MTBE followed Lanmuir-Hinshelwood kinetics with a linearity of 0.989. As far as the mechanism of degradation is concerned, attack by generated hydroxyl radicals on the methoxy group in the MTBE structure dominated and proceeded through tert-butyl formate (TBF) as an intermediate, instead of methyl group to proceed through producing 2-methoxy-2-methyl propionaldehyde (MMP). TBF finally degrades to CO2 through acetone, which was shown easily converted to CO2. This study shows that the use of sunlight seems to be possible given adequate tools for concentrating the light. 相似文献