Study on Laboratory Method for Refining of SR Diesel Fuel

The method for refining the straight-run diesel fuel was studied in laboratory scale in order to make the acid number of diesel fraction comply with the standard while removing the naphthenic acids contained in diesel without causing environmental pollution. After comparing the effect of refining using three solvents, the isopropyl alcohol-HOA was specified as the best solvent. Meanwhile, the relationship between the acid number of diesel fraction and the amount of solvent used and the relationship between the concentration of solvent and temperature and the stability of diesel in terms of its acid number were also investigated. Experimental results had shown that when the mass fraction of the HOA-IPA solvent was 20% at a dosage of 17 mL of the solvent and a temperature of 30℃, the acid number of the refined diesel fraction was 0.015 mg KOH/g with a good stability of acidity in the diesel fraction,     

浅析承钢化学产品脱酸蒸铵系统堵塞与腐蚀原因及对策

分析了承钢化学产品脱酸蒸铵系统堵塞与腐蚀的原因,从工艺和设备等方面采取了有效措施,取得了较好的经济效益.     

Immobilised yeast grape must deacidification in a recycle fixed bed reactor

Maloalcoholic fermentation (MAF) of grape must by Schizosaccharomyces pombe immobilised in calcium‐alginate double‐layer beads (ProMalic^®) was studied in Erlenmeyer flasks and in a total recycle fixed‐bed reactor operating in batch mode. The reaction is pseudo‐first order with respect to l ‐malic acid and under similar conditions deacidification is faster in the recycle reactor. This was attributed to mass transfer limitations which were confirmed in the recycle reactor by studying the influence of yeast load on the rate of MAF. Mass transfer limitations are also responsible for the lower activation energy of fermentation with the immobilised yeast (67 ± 9 kJ mol^?1) in comparison with the free cells (126 ± 19 kJ mol^?1). Alcoholic fermentation and MAF were performed simultaneously, both in the recycle reactor and in the industrial trials, confirming the efficacy of immobilised S. pombe to reduce grape must acidity without interfering with the main fermentation. Altogether, the present results are useful for the scale‐up of a recycle reactor to process large volumes of grape must.     

Phytosterol Enrichment of Rice Bran Oil by a Supercritical Carbon Dioxide Fractionation Technique

Supercritical carbon dioxide (SC–CO₂) fractionation technique was evaluated as an alternative process for reducing the free‐fatty‐acid (FFA) content and minimizing the phytosterol loss of rice bran oil (RBO) during the process. The effects of pressure (20.5 to 32.0 MPa) and temperature (45 to 80 °C) for isothermal operation of the column on the composition of the resultant fractions were examined. Low‐pressure and high‐temperature conditions were found to be favorable for minimizing triglycerides (TG) and phytosterol losses during the FFA removal from crude RBO. Rice bran oil fractions with < 1% FFA, about 95% TG, and 0.35% free sterol with 1.8% oryzanol content could be obtained utilizing the described SC–CO₂ fractionation technique.     

油酸改性纳米Mg(OH)2 用于纸张脱酸

利用油酸对纳米Mg(OH)2粒子进行改性,使其均匀分散在六甲基二硅醚中,制备成稳定的脱酸液;并将该脱酸液喷涂在老旧纸张上进行纸张脱酸。结果表明,采用0.1 g油酸、1g纳米Mg(OH)_2、100mL六甲基二硅醚,在反应温度50℃、反应时间1h的条件下获得的改性纳米Mg(OH)_2在六甲基二硅醚中具有良好的分散性,可作为脱酸液用于纸张的脱酸。当脱酸液涂布量为2.7 g/m~2时,相对于未脱酸纸,脱酸纸的表面pH值得到了明显提高(从4.00提高到7.92),纸张抗张指数和撕裂指数基本没有变化;经加速老化处理后,脱酸纸表面pH值为7.60左右,抗张指数和撕裂指数稍有下降,但远低于未脱酸纸;加速老化后,脱酸纸的色差为0.64,符合纸张文物"修旧如旧"的原则。     

精制核桃油生产工艺及其氧化稳定性的研究

研究了利用物理压榨法制备核桃油及其精炼工艺，然后取等重的9组样品，分别添加不同的抗氧化剂TBHQ、PG、BHT、VE及增效剂柠檬酸、抗坏血酸(Vc)，与空白样一起利用Schaal烘箱法每隔24h测一次过氧化值(POV)，比较它们的氧化稳定性。试验结果表明：焙炒、脱酸、脱胶是精制核桃油的关键工序，其工艺条件依次为：焙炒温度130℃、时间30min；碱法脱酸：碱液浓度11％、碱炼初温40℃。加碱量为理论碱量和超碱量之和；磷酸脱胶：油重0．2％的85％磷酸、3％的水、温度保持在60℃；添加0．02％TBHQ、0．01％PG和0．015％Vc复合抗氧化剂的油样(在60℃通风条件下贮藏408h的过氧化值最低为0．75meq／kg，国家标准规定过氧化值≤10nmeq／kg，经计算其在20℃存储保质期可达22个月以上。     

The catalytic deacidification of acidic crude oil using Cu-doped alkaline earth metal oxide catalysts

Naphthenic acids (NAs) tend to cause operational problems that can lead to the deactivation of catalysts. To overcome the problem, catalytic deacidification was introduced utilizing an ammonia solution in ethylene glycol with the aids of alkaline earth metal catalyst with alumina as a support. The initial total acid number observed for NAs in n-dodecane was 4.21 mg KOH/g. In total, 1,000 mg/L of 0.4% NH₃-EG were used as the acid removal agent. Calcium, barium, and magnesium catalysts were tested in this study. The results showed Cu/Ca/Al₂O₃ was found to be the best catalyst that could be used to enhance the reaction.     

微波水热法制备纳米ZnO应用于纸张脱酸加固初探

以乙酸锌和六次甲基四胺(HMT)为前驱体制成水溶液(n(乙酸锌)∶n(HMT)=1∶5),将纸质文物浸泡后放入微波炉低火加热.通过对处理前后纸样的外观、pH值、抗张强度等性能测定及SEM分析,综合评估其脱酸加固效果.结果表明:经前驱体溶液浸泡并微波加热后,纸张pH值呈上升趋势;HMT有利于提高纸张抗张强度,HMT含量达...     

Debittering and Deacidifying Sour Orange (Citrus aurantium) Juice Using Neutral and Anion Exchange Resins

Juices from four cultivars of sour orange (Citrus aurantium), Seville, Bigaradier, Sour and Bittersweet, were treated with neutral (XAD-16) and weak base anionic exchange (IRA-93) resins. Unidentified fluorescent compounds were removed along with bitter compounds by both resin treatments. Average acidity was reduced from 57–87% using IRA-93 before depletion. Average naringin concentrations were reduced 50–66% in high acid juice and 89% in low acid juice using IRA-93. Under similar conditions 24–30% of the limonin was eliminated using IRA-93 and essentially 100% removed using XAD-16. Sensory acceptance (9-point hedonic scale) improved from 1.6 to 3.0 after IRA-93 resin treatment of a high acid juice. Average acceptance increased from 3.8 to 6.4 after XAD-16 treatment of a low acid juice.