Optimization and Characterization of Biosurfactant Rhamnolipid Production by Pseudomonas aeruginosa Isolated from an Artificially Contaminated Soil

Biosurfactants are surfactants biologically produced by microorganisms, presenting several advantages when compared to synthetic surfactants. Pseudomonas aeruginosa is known for producing rhamnolipids, considered one of the most interesting types of biosurfactants due to their high yields, when compared to other types. In this work, the production of rhamnolipid from P. aeruginosa was optimized. At first, the Plackett–Burman design was used to select most significant variables affecting the biosurfactant production yield among nine variables—carbon–nitrogen ratio, carbon concentration, nitrogen source, pH, cultivation time, potassium and magnesium concentrations, agitation, and temperature. Then, using main variables, a central point experimental design aiming to optimize rhamnolipid production was performed. The maximum biosurfactant concentration obtained was 0.877 mg L⁻¹. The rhamnolipid also displayed a great emulsification rate, reaching approximately 67%, and the ability to reduce water surface tension from 72.02 to 35.26 mN m⁻¹ at a critical micelle concentration (CMC) of 127 mg L⁻¹, in addition to presenting a good stability when exposed to wide pH and salinity ranges. The results suggest that rhamnolipids are promising substitutes for synthetic surfactants, especially due to lower impacts on the environment.     

利用地沟油和对苯二甲酸废料生产醇酸树脂的理论和实践

以地沟油和对苯二甲酸废料为原料合成醇酸树脂,通过对原料的组成及合成工艺的理论分析,确定采用碱漂法去除地沟油的杂质,采用混合酸多步法除去对苯二甲酸废料中的杂质,采用二段法合成醇酸树脂。经中试和扩大生产,合成的醇酸树脂固形物中40%来自地沟油,25%来自对苯二甲酸废料,其余为甘油和松香,与传统工艺相比,本工艺生产醇酸树脂每吨原料成本降低1 522元,是一条经济有效的资源化利用工艺路线。     

Optimization of Deacidification of Mixtures of Sunflower Oil and Oleic Acid in a Continuous Process

Mixtures of refined sunflower seed oil and oleic acid were deacidified using nitrogen as stripping gas in a pilot-plant scale continuous deodorizer. To optimize the process, two different levels were tested for the classical operating parameters of oil temperature, nitrogen flow rates, oil mass flow rates and initial free fatty acid contents. In addition, two heating procedures were tested, including one using separate electrical heating of the oil and gas distillates to maintain the same temperature in both parts of the deodorizer, and another in which only the oil was heated and controlled, resulting in a temperature difference between the oil and the gas distillates. The statistical technique of blocking with paired comparisons was used to analyze the final free fatty acid content, rate of free fatty acid loss with respect to the processed oil flow rate, free fatty acid content in the distillates recovered by condensation, and efficiency. The results showed that the oil temperature and maintaining the same temperature in the oil and the gas distillates produced the most relevant effects, having a positive effect on most of the responses.     

多价不饱和脂肪酸分离方法及在橡胶籽油中的应用

介绍了多价不饱和脂肪酸的分离纯化方法 ,以及在橡胶籽油中的应用前景。     

炼油厂酸性废水及碱渣综合处理技术的改进

该公司以低硫含量的大庆原油为原料,DCC-Ⅱ型催化裂解酸性废水汽提工艺所产H2S量不足以维持制硫磺装置,而焚烧后排放大气的SO2又超标。用西安湘德环保科技有限公司酸性水脱硫专利技术,处理后的净化水pH=9~10,硫化物质量浓度<60mg/L,但氨氮浓度>600mg/L。将该工艺由先脱氨后脱硫改造为先脱硫后脱氨后,氨氮质量浓度降到30~80mg/L,其余指标合格不变。     

Taguchi Method and Grey Relational Analysis to Improve in Situ Production of FAME from Sunflower and Jatropha curcas Kernels with Subcritical Solvent Mixture

This study investigates the possibility of employing in situ (trans)esterification (ISTE) under the subcritical condition (200–250 °C) of the solvent mixture (methanol + acetic acid) with a high solid loading and a low solvent to solid ratio (SSR). The Taguchi method together with grey relational analysis was used to improve both FAME yield and productivity. It was found that temperature reaction time and SSR were factors which contributed the most in obtaining high FAME yields. In addition to the above‐mentioned factors the addition of acetic acid also significantly improved the productivity. Employing the following conditions: 250 °C; 8.8 MPa; 3–7 mL/g SSR; 10 % acetic acid was found to provide an improved FAME yield and productivity. A confirmatory test resulted in a FAME yield of 87.5–92.7 % for sunflower kernels and 88.2–97.22 % for Jatropha curcas L. kernels and productivity up to 37.5 kg/m³/h can be obtained with good repeatability. Furthermore, the process developed in this study can tolerate moisture and a free fatty acid content of up to 25 %. The direct application of the method using whole kernels was also investigated.     

桐油基阻燃多元醇制备及其在硬质聚氨酯泡沫中应用

以桐油(TO)为基本原料,先后经过酯交换反应、磷钨酸季铵盐催化环氧化反应、环氧开环反应生成桐油基阻燃多元醇(TOBP),并将制备的TOBP与异氰酸酯(PAPI)共混通过一步发泡的方式制备得到阻燃型硬质聚氨酯泡沫(FRPUR)。采用傅立叶变换红外光谱和氢谱对产物的结构进行表征,分析结果表明,已成功制备出环氧中间体和TOBP;热重测试结果表明TO、桐油甲酯(TOME)、环氧桐油甲酯(ETOME)和TOBP的热稳定性顺序依次为TOBPETOMETOTOME。通过发泡和极限氧指数、力学强度等测试手段,考察了桐油基PUR泡沫的阻燃性能和力学性能,并与由工业级聚醚多元醇制备的FRPUR硬泡进行比较。分析测试结果表明,由TOBP制备的FRPUR具有良好的阻燃性能和力学性能。     

热管技术在硫酸生产中的应用

热管技术应用于硫酸生产的中温余热回收，效果明显，具有一定的推广价值。     

烃中微量水的计算及在炼厂的应用

炼化企业各个单元由于烃或油中所含微量水对物流表观热力学行为影响不大,故正常设计时往往关注烃水液液平衡,而忽略汽液平衡行为。探讨了烃水相平衡的计算,利用Aspenplus对比了计算结果与实验数据的偏差,验证精度。在此基础上,对炼厂气分单元丙烯微量水的控制、柴油加氢单元柴油微量水的控制2个实例进行了计算,并对比工业运行数据。结果表明,Aspenplus对微量水的计算,对炼厂烃中微量水控制有较强的指导意义,能够解释烃中微量水的＂反常＂行为,可以在设计和生产中作为计算依据。     

我国脂肪酸的生产和应用

简要介绍脂肪酸的分类、原料来源、生产工艺、品种以及用途。并对我国脂肪酸的生产现状进行了分析。重点介绍了脂肪酸在我国橡胶工业中、塑料助剂等领域的应用,脂肪酸甲酯作为表面活性剂在不同领域的广泛应用,最后还简述了癸二酸和改性醇酸树脂应用。     

利用KNO3生产中的废酸制备活性白炭黑

直接法生产硝酸钾过程中产生大量含钾废酸，若不回收利用，将严重影响硝酸的生产。本文介绍了一种利用含钾废酸生产活性白炭黑的方法，既变废为宝，又降低了活性白炭黑的生产成本。     

从酸性蚀刻废液中回收盐酸及生产高纯电镀级硫酸铜的研究、应用

文章主要论述一种新型酸性蚀刻废液处理方法,在特制石墨蒸酸釜内加入定量的酸性蚀刻废液及98%硫酸,在蒸汽不断加热下使得反应液内部氯化氢气体不断逸出,通过冷凝回收盐酸,同时所得粗品硫酸铜通过重结晶除杂的方法得到高品味的电镀级硫酸铜。该处理工艺全过程无废水产生,回收盐酸回用于蚀刻液的配制,达到了资源回收利用之目的,所得铜产品提升了其附加值,是当前所有处置工艺中最环保的处理方法之一。     

国产化大型电除尘器的设计及在硫酸生产中的应用

总结了引进的大型电除尘器在硫铁矿制酸和冶炼烟气制酸装置中运行时存在问题的基础上,对单电场的有效长度、振打清灰效果等问题进行了改进,使我国自行设计、制造的硫酸生产用的大型电除尘器满足了长期稳定运行的要求,各项性能指标达到了设计要求,认为今后可以用国产化大型电除尘器代替引进设备。     

我国柠檬酸的生产应用与开发

概述了柠檬酸在我国的生产、开发与应用情况,对我国柠檬酸行业的发展提出若干建议。     

腐植酸在烟草生产中的应用研究进展

综述了腐植酸在烟草生长发育中改良土壤、增加肥效、增加药效、提高烟草品质、保持生态环境,以及对烟株生长发育的影响,包括烟株的生长、营养元素的吸收、蛋白质和核酸的合成、光合作用、呼吸作用以及有些酶的活性等.并提出了该研究领域目前存在的问题及今后的研究重点,为腐植酸在烟草上进行大面积应用提供依据.     

浓硝酸、硝盐生产中废水处理方法探讨

探讨了硝法浓硝酸、硝酸铵、硝酸钠和亚硝酸钠工业生产废水的处理方法:①利用间硝法浓硝酸生产中排出的2.5%酸水代替浓度为30%的盐酸用于450 t/h一级除盐水装置;②采用膜分离法,将硝铵废水经膜分离处理,浓水回收返回生产系统,淡水作为锅炉用水或循环水的补充水。通过生产运行数据总结了废水处理效果。结果表明,把废水处理与回收利用、产品回收相结合的废水处理方法,可以达到节能和零排放的目的。     

高铬铁素体不锈钢在硫酸和湿法磷酸生产中的应用

在当今金属镍价格不断上涨的情况下,开发和使用不合贵重金属镍而力学性能和耐腐蚀性能都十分优良的高铬铁素体不锈钢具有很重要的经济意义：调整高铬铁素体不锈钢中的碳含量,可改变其物化性能,介绍了超低碳、低碳和高碳高铬铁素体不锈钢的特点,以及它们在高温浓硫酸和湿法磷酸生产设备中的应用情况。     

CLT-酸生产中还原铁泥和废硫酸的治理与利用

将30％—35％的废硫酸加热至90℃-100℃，在搅拌下加入生产CLT酸的还原铁泥，然后过滤、脱色、结晶，在300℃下脱水得硫酸亚铁白色粉末。将精制的硫酸亚铁在800℃下锻烧2—2．5小时，再经大型研磨得氧化铁红。讨论了预处理、反应条件等因素对氧化铁红质量的影响。     

含砷硫铁矿制硫酸的危害及其防止

介绍硫酸生产对原料硫铁矿含砷量的要求,论述制酸过程中行为及其危害性,指出如何治理含砷污水和酸泥,如何防止含砷硫铁矿对制酸的危害。     

Electricity Generation and Wastewater Treatment of Oil Refinery in Microbial Fuel Cells Using Pseudomonas putida

Microbial fuel cells (MFCs) represent a novel platform for treating wastewater and at the same time generating electricity. Using Pseudomonas putida (BCRC 1059), a wild-type bacterium, we demonstrated that the refinery wastewater could be treated and also generate electric current in an air-cathode chamber over four-batch cycles for 63 cumulative days. Our study indicated that the oil refinery wastewater containing 2213 mg/L (ppm) chemical oxygen demand (COD) could be used as a substrate for electricity generation in the reactor of the MFC. A maximum voltage of 355 mV was obtained with the highest power density of 0.005 mW/cm² in the third cycle with a maximum current density of 0.015 mA/cm² in regard to the external resistor of 1000 Ω. A maximum coulombic efficiency of 6 × 10⁻²% was obtained in the fourth cycle. The removal efficiency of the COD reached 30% as a function of time. Electron transfer mechanism was studied using cyclic voltammetry, which indicated the presence of a soluble electron shuttle in the reactor. Our study demonstrated that oil refinery wastewater could be used as a substrate for electricity generation.