一株节杆菌脱硫特性的初步研究

从油污染的土壤样品中筛选出一株能将二苯并噻吩（DBT）代谢为2-羟基联苯（2-HBP）的脱硫菌株T1，初步鉴定其属于节杆菌属（Arthrobacter.sp）。在0.5mmol/L DBT浓度下,菌株具有较高的脱硫活性；相对于硫酸钠、二甲基亚砜为唯一硫源，T1菌株更容易利用DBT；在硫酸钠初始浓度大于0.5mmol/L时几乎无2-HBP生成；在2-HBP初始浓度大于0.5mmol/L时对T1的生长有明显的抑制作用。     

施氏假单胞菌UP-1降解二苯并噻吩的动力学模型

对施氏假单胞菌(UP-1)降解二苯并噻吩（DBT）的过程进行了宏观动力学研究,以Michaelis-Menten方程为基础确定了UP-1降解DBT的动力学模型。计算得到动力学参数vmax=84.75 mg/(l·h), Km=759.59 mg/l。通过相关指数R2和F值检验,该动力学模型高度显著,两个重要参数取值可信。在考察的底物浓度范围内菌株UP-1降解DBT过程不存在底物抑制作用,但存在产物抑制作用。求得的UP-1休止细胞降解DBT的最大降解速率为88.5 mmol/(kg DC·h),其降解脱硫能力优异。     

柴油循环生物脱硫的实验研究

以二苯并噻吩(DBT)中的有机硫为唯一硫源，筛得一株可专—断裂C—S键的菌株——红球菌DS-3。用摇瓶多批次脱硫法对柴油进行生物脱硫实验，经五次循环后可脱除0号柴油中52．13％的有机硫，87．53％的DBT转化为不含硫的二羟基联苯(2-HBP)。色谱分析表明,0号柴油中正构烷烃含量在生物脱硫前后始终保持在50％以上．油中的烃类组分基本不变。     

直流电场对脱硫菌红串红球菌NCC-1生长及脱硫性能的影响

以专一性降解二苯并噻吩(DBT)的红串红球菌NCC-1为脱硫菌,以DBT为硫源,考察了加直流电场对脱硫菌在不同浓度DBT水相中生长和脱硫性能的影响,以及调控菌液pH对脱硫菌生长和脱硫性能的影响;同时考察了脱硫菌对柴油的脱硫性能。实验结果表明,当电流密度为0.52～1.01A/m2时,能有效促进脱硫菌生长,提高脱硫效率,最佳电流密度为0.72A/m2,当DBT初始浓度为0.20mmol/L时,DBT完全降解的时间为120h,比不加电场时缩短了24h;当DBT初始浓度为1.00mmol/L时,DBT浓度降至0.31mmol/L所需时间为72h,比不加电场时缩短了96h。此外,调控菌液pH能有效促进脱硫菌生长。脱硫菌用于柴油脱硫时,在电流密度为0.72A/m2、柴油与菌液体积比1∶9的条件下,总硫含量从606mg/L降至269mg/L,脱硫率为55.7%,比不加电场时高出12.9个百分点。     

细胞工程菌脱除油品中有机硫的实验研究

考察了具有自主知识产权、通过原生质体跨界融合获得的脱硫细胞工程菌菌种对不同油品中有机硫化合物的脱除能力。实验结果表明,该细胞工程菌可同时脱除苯并噻吩、二苯并噻吩、4,6-二甲基二苯并噻吩及苯硫醚等多种复杂有机硫化合物,并且该细胞工程菌可直接脱除不同石油产品中的有机硫,尤其对加氢精制后油品中残余硫的脱除效果显著。     

Ce(SO4)2-HCl体系模拟柴油脱硫反应研究

以Ce（SO4）2-HCl体系为氧化体系,N,N-二甲基甲酰胺（DMF）为萃取剂,在石油醚中加入一定量的二苯并噻吩（DBT）构成柴油模拟体系,通过正交实验得出最佳脱硫条件：pH值为1,Ce（SO4）2加入量为0．008g／mL（油）、温度为30℃、时间为50min、V盐酸介质：V柴油=4：5。通过模型参数估值和曲线拟合得出反应级数为1．3,探索出最优条件下反应动力学方程。Ce^4＋氧化媒质可用电化学方法再生循环利用,具有很好的经济效益,符合绿色化学发展的态势。     

二苯并噻吩脱硫菌Rhodopseudomonas sp. AS-21的脱硫条件优化

以二苯并噻吩(DBT)为模式物筛选得到专一性脱硫菌Rhodopseudomonas sp.AS-21。通过单因素考察实验结果分析温度、pH、碳源、氮源和DBT初始浓度对脱硫率和细胞浓度的影响,得出菌株的最适宜生长和脱硫条件:培养温度为30℃,初始pH为7.5,碳源为10g/L甘油,氮源为2g/L的氯化铵,DBT初始浓度为100mg/L。利用Design-Expert软件进行显著性分析,结果表明温度、pH、DBT浓度影响的显著性较高。采用Box-Behnken Design(BBD)响应曲面法设计三因素三水平共20组实验,得到脱硫率和细胞质量浓度的二次回归模型。在Design-Expert软件模拟的条件下,以响应值最大为目标进行优化求解,结果表明在温度为29.70℃、pH为7.43、DBT初始浓度为105.47mg/L时可得到最大脱硫率(72.32%)及最大菌株生长量(2.311g/L)。经实验验证,所求最优解正确。     

喹啉对Co-Mo/Al_2O_3催化二苯并噻吩加氢脱硫的反应动力学研究

在柴油加氢脱硫(HDS)催化剂FHUDS-5(Co-Mo/Al2O3)上,模拟工业高压搅拌反应釜生产工艺,考察了喹啉对二苯并噻吩(DBT)HDS反应活性的影响,并对其反应动力学进行了研究。结果表明,DBT的HDS反应主要通过加氢路径(HYD)和氢解路径(DDS)进行,符合一级反应动力学模型;当喹啉浓度很低时,其对DBT加氢脱硫反应的抑制作用强烈,但随着喹啉浓度的增加,这种抑制作用不再明显;当n为0.25时,喹啉对DBT加氢脱硫反应活性的影响符合于rDBT=kDBTCDBT/(1+Kn NCn N)动力学模型。     

柴油脱硫菌的特性研究

针对传统加氢脱硫方法难以脱除柴油中含有的大量以噻吩、二苯并噻吩（DBT）等形式存在的含硫化合物,以DBT为模型化合物,筛选出以DBT为唯一硫源且降解DBT较好的菌株HT1,正交实验确定菌株发酵最佳条件为：温度30 ℃,硫源DBT质量浓度102.0 mg/L,氮源NH4NO3质量浓度2.0 g/L,碳源甘油质量浓度5 g/L,培养时间4 d,pH值7.0。硫源对菌株HT1的生长及脱硫效果的研究结果表明：硫源对菌株HT1的生长影响不大,但菌株HT1对以DBT为硫源的脱硫效果最佳。菌株HT1对其它含硫化合物的脱硫效果与含硫化合物的结构有关。菌株HT1对催化裂化柴油的脱硫率较低,有待进一步提高。     

乳酸基低共熔溶剂中钼酸铵催化氧化脱硫性能研究

以己内酰胺为氢键受体、乳酸为氢键供体,合成了乳酸基低共熔溶剂,通过傅里叶变换红外光谱和氢核磁共振波谱分析表征确定了己内酰胺和乳酸间的氢键作用。以二苯并噻吩（DBT）与正辛烷混合得到的模拟油（简称DBT模拟油）为原料,以乳酸基低共熔溶剂为萃取剂和助催化剂、过氧化氢（H₂O₂)为氧化剂、钼酸铵为催化剂进行氧化脱硫试验,考察反应温度、n(H₂O₂)/n(DBT)、钼酸铵加入量、剂油体积比及硫化物类型对模拟油脱硫率的影响,确定最佳反应条件：反应温度为70 ℃,反应时间为100 min,n(H₂O₂)/n(DBT)为6∶1,钼酸铵质量浓度为4 g/L,剂油体积比为1∶10。在最佳反应条件下,DBT模拟油、4,6-二甲基二苯并噻吩模拟油和苯并噻吩模拟油的脱硫率分别为100%,98%,78%。脱硫反应重复进行5次后,乳酸基低共熔溶剂对DBT模拟油的脱硫率仍可达到95%,具有较好的重复使用性能。     

钨酸铋的制备及其催化氧化脱硫性能

催化氧化脱硫法因反应条件温和、可高效深度脱除燃料油中二苯并噻吩(DBT)类硫化物,是一种有潜力的非加氢脱硫方法。以钨酸钠和五水合硝酸铋为原料,采用直接沉淀法和水热法制备钨酸铋(Bi₂WO₆)。采用傅里叶变换红外光谱(FT-IR)、X-射线衍射(XRD)、电子扫描显微图像(SEM)、能量色散X射线光谱(EDS)和N₂等温吸附-脱附等分析方法对其结构、组成、表面形貌和比表面积进行表征。分别以DBT、苯并噻吩(BT)、4-甲基-二苯并噻吩(4-MDBT)和4,6-二甲二苯并塞吩(4,6-DMDBT)为代表性硫化物,以正癸烷为溶剂、十四烷为内标物配制含硫模拟油,以制备的Bi₂WO₆为催化剂、过氧化氢(H₂O₂)为氧化剂、乙腈(CH₃CN)为萃取剂构建催化氧化脱硫体系,系统地考察了其催化氧化脱硫性能。结果表明,水热法制备的Bi₂WO₆(BWO-2)表现出较优的脱硫性能。在反应温度...     

二苯并噻吩在催化裂化过程中的转化规律研究

在小型固定流化床（FFB）装置上以二苯并噻吩（DBT）-十六烷体系为原料,研究DBT在催化裂化过程中的转化规律。结果表明,在反应温度500 ℃、剂油质量比6、空速10 h-1的条件下,DBT的转化率为45%左右。在DBT参与的反应中,烷基化反应占主要地位。DBT转化为甲基苯并噻吩的比例最高,其次为C2～C5的烷基二苯并噻吩。DBT-十六烷反应体系的硫90%左右分布在催化裂化液体产品中,少量反应生成硫化氢,少量进入焦炭中。DBT的加入降低了十六烷的转化率,促使干气生成,汽油产率减少,柴油产率增加,焦炭产率显著增加。     

NiW/Al2O3上喹啉对二苯并噻吩 加氢脱硫的抑制作用及反应动力学

 以二苯并噻吩(DBT)为含硫模型化合物，在中压滴流床反应装置中研究了工业NiW/Al₂O₃催化剂(RN-10)上喹啉对DBT加氢脱硫(HDS)的抑制作用，考察了喹啉质量分数(0.5%~1.5%)、反应温度(290~380℃)、反应压力(4.0~5.6MPa)对DBT的HDS的影响。结果表明，喹啉的存在对于DBT的HDS反应有很强的抑制作用，且喹啉浓度越高，抑制作用越大；对DBT的先加氢饱和再脱硫路径(HYD)的抑制作用比对直接脱硫路径(DDS)更大；提高反应温度对DDS和HYD路径的脱硫活性均有提升，但由DDS路径生成联苯的选择性降低；较高反应压力有利于提高HYD路径产物的选择性。采用带有氮化物吸附(中毒项)的拟一级反应动力学模型对实验数据进行拟合，得到不同喹啉质量分数下DBT的HDS表观反应速率常数。经检验，模型计算结果与实验结果吻合。     

Main and Interactive Effects of Polyaromatic Sulfur Heterocyclic Compounds on Growth and Biodegradation Efficiencies of Bacillus sphaericus HN1: Modeling and Statistical Analysis

Bioremediation is an effective technique to remediate soil and water contaminated with a mixture of recalcitrant polyaromatic sulfur heterocyclic (PASH) compounds. Based on two levels of full factorial design, a statistical design of experiments was used in this study to investigate the interactive effects of three PASHs; thiophene (Th), benzothiophene (BT), and dibenzothiophene (DBT) on their biodegradation in multisubstrate batch process using Bacillus sphaericus HN1. Kinetic modeling was performed to estimate the rate of biodegradation of each PASH in single-, binary-, and tertiary-substrate systems. Biodegradation of BT, DBT, and total PASHs follows the first order kinetic reaction in the single- and multisubstrate batch systems, while biodegradation of Th follows the first-order kinetic reaction, in single-substrate system, but second-order kinetic reaction in multisubstrate batch system. Four linear interaction regression models were estimated and validated to describe the interactive effect of the three PASHs on their biodegradation. Statistical analysis of the results in the form of analysis of variance and Student t test indicated significant role played by the main effects of Th, BT and DBT on their biodegradation (p < 0.01). Th and the interactive effect between Th and DBT has statistically significant negative effect on DBT removal (p = 0.0665). However, DBT expresses higher statistically significant positive effect on total PASHs removal than that of Th (p = 0.0178 and p = 0.026, respectively), but their interaction has a significantly negative effect (p = 0.0143).     

An Improved Desulfurization Process Based on H2O2/Formic Acid Oxidation and Liquid-Liquid Extraction 2. FCC Diesel Oil Feedstocks

Semi-empirical molecular orbital theory and parametric model 3 methods were used to calculate the quantum chemistry properties of dibenzothiophene (DBT) and its corresponding sulfone compounds to investigate the essential theory of a formic acid/H₂O₂ oxidation desulfurization system. To study oxidation kinetics of the oxidation desulfurization reaction, DBT was also employed as a model compound to obtain the oxidation kinetic parameters. Desulfurization of fluid catalytic cracking (FCC) diesel was also performed in this process, and the sulfur content was reduced from 7,200 μg·g^-1 to 598 μg·g^-1 after being extracted by polyethylene glycol 200.     

A Two-stage Immobilized Cell Bioreactor With Bacillus subtilis and Rhodococcus erythropolis for the Simultaneous Production of Biosurfactant and Biodesulfurization of Model Oil

Two vertical rotating immobilized cell reactors (VRICRs), one with the bacteria Bacillus sp. BDCC-TUSA-3 and the other with R. erythropolis, were constructed, with polyurethane foams as an attachment support. They were optimized for surfactin production and biodesulfurization (BDS) of dibenzothiophene (DBT), respectively. Then, the two bioreactors were combined to form a two-stage VRICR where an appropriate fraction of Bacillus sp. reactor effluent, containing surfactin, was mixed with the influent fed into R. erythropolis bioreactor, containing DBT in hexadecane. The BDS rate and volumetric reactor productivity were greatly increased to 210.5 mM 2HBP.kg^?1.h^?1 and 16.6 mM 2HBP.L^?1.h^?1, respectively. Sulfur concentration decreased from 398 down to <5 ppm. Additionally, surfactin was produced at high concentration (4.8 g.L^?1) with a volumetric reactor productivity of 720 mg_surfactin·L^?1.h^?1, which represents an extra added-value product that could markedly decrease operating costs. This study presents a feasible technology for efficient removal of sulfur from sulfur-containing fossil fuels and the production of biosurfactant as well.     

The Reaction Kinetics of a Fischer-Tropsch Synthesis Over a Commercial Eggshell Co/SiO2 Catalyst

Abstract

The comprehensive kinetic model of Fischer-Tropsch synthesis over a commercial eggshell Co/SiO₂ catalyst in a fixed-bed reactor was investigated experimentally. This model was expressed in the combination of kinetic rate of CO consumption and the equation of the growth probability factor α was obtained. Through parameter evaluation and optimization, both the rate of CO consumption was given and the equation of a was obtained. It was also proved that the proposed model could predict the kinetic rate of CO consumption and the product distributions well. The appropriate operating conditions for this catalyst were concluded by the model and they were in good agreement with the results in the industrial pilot-scale research.