膜分离-氧化法去除草甘膦生产线上副产盐中的有机物

[目的]草甘膦生产线上副产盐中有机物含量很高,难以用于其他行业,大量氯化钠资源被浪费。探索新工艺去除副产盐中的有机物,实现废物资源化利用。[方法]根据副产盐中有机物的性质,采用膜分离-氧化工艺,先用膜截留大分子有机物,再将透过膜的小分子有机物氧化去除,得到精制盐水。[结果]通过纳滤膜分离-NaClO氧化工艺,其精制盐水的TOC小于20 mg/L。[结论]该工艺能够有效去除草甘膦生产线上副产盐中的有机物,解决了副产盐无法用于其他行业的难题。     

水合肼副产盐渣回收利用扩试研究

水合肼生产中副产大量盐渣,这种盐渣中因含有少量水合肼、尿素等有害杂质,不能直接作为原料盐用于氯碱工业,必须除去盐渣中的氮。利用自主研发的专利设备及工艺,用高温法对水合肼副产盐渣的回收利用进行了规模为15 t/a的扩试研究。结果表明,在热分解温度为450℃、加料量为2.0 kg/h、停留时间为6 h的条件下,经处理后的盐总氮质量分数2×10-5,可完全满足氯碱工业用盐要求。为水合肼副产盐渣的资源化利用开辟了一条可行的技术路线。     

PVC副产盐酸脱吸新工艺

介绍了山东新龙集团有限公司自主研发的PVC副产盐酸脱吸新工艺,采用该工艺脱吸的氯化氢不含游离氯,含水体积分数小于2×10^-4,可作为生产三氯氢硅的原料气,实现了酸水零排放,解决了PVC生产中的废酸排放问题。     

膜分离耦合氧化技术降解草甘膦副产盐中有机物

甘氨酸法生产草甘膦,产生了大量的草甘膦副产盐,由于其有机物含量较高,无法在其他行业得到应用,导致了大量副产盐的浪费。探索副产盐中有机物的去除方法,实现草甘膦副产盐的资源化回用。膜分离技术去除大部分大分子量有机物,再采用氧化技术去除膜淡液中少部分有机物。通过膜分离耦合氧化技术处理后,达到了一次精制盐水指标。通过本技术的处理,草甘膦副产盐中的有机物得到了有效去除,草甘膦副产盐在其它行业得到应用成为可能。     

高压法三聚氰胺生产装置废水处理系统故障分析及改造

简要介绍了OAT的产生及处理过程，对废水处理系统出现的故障进行分析并采取了相应的改造措施。废水处理系统的正常运行确保了三聚氰胺装置安全环保运行，高压水解系统分解得到的甲铵液送化肥或尿素装置回收利用；处理后的水总氨氮质量分数〈50×10^-6，COD质量分数〈150×10^-6，实现了工业废水的零排放和资源的循环利用。     

德国汉高新系列乐泰黏合剂和密封剂上市

为响应减少使用卤化材料以保护环境的倡议，德国汉高公司日前推出新系列的乐泰黏合剂和密封剂，主要用于便携电子设符。配方中溴和氯的质量分数低于9×10^-4，总卤质量分数低于1．5×10^-3。这些产牖所含的卤素水平很低，往往低于可检测值。     

有机废水中盐含量对膜蒸馏处理性能的影响

采用真空膜蒸馏技术对高盐有机废水进行浓缩回收。考察了废水进料温度、真空度、进料流速、废水盐度、废水的进料方式等因素对膜通量和截留率的影响。结果表明,在常压循环方式进料,透过侧真空度0.04～0.095 MPa,进料温度为30～80℃,进料流量为40～160 L/h的条件下,通过实验设计的膜蒸馏过程,可以将质量分数为10%盐度的有机废水,COD〉7 500×10^-6,浓缩至质量分数为30%盐度的有机废水,透过水的盐度〈0.01%,COD〈20×10^-6,通过盐结晶方法去除相应有机物后,可获得纯度较高的工业盐。     

EPA要求2017年起大幅削减汽油中硫含量

美国环境保护署（EPA）于日前宣布，从2017年开始，所有在美国市场出售的汽油产品中硫质量分数必须不大于10×10^-6。延期已久的Tier3（第三阶段汽车废气排放和燃料标准计划）要求美国汽油硫质量分数从当前的30×10^-6降至10×10^-6以下，同时要求削减其他有害的汽车尾气排放。EPA表示，原油中自然存在的硫元素是降低汽车尾气催化转化器效率的主要因素，而汽车尾气催化转化器可以消除导致哮喘和肺部疾病的烟雾排放。环保和公共健康组织对此方案表示支持。EPA表示，汽油中硫质量分数的大幅削减将带来显著的空气质量和健康益处。     

草甘膦副产盐精制用于离子膜烧碱的研究

为使草甘膦副产盐能用于离子膜烧碱,对此进行了精制研究,考察了煅烧温度、煅烧时间、除磷氧化钙加入量等因素对盐水品质的影响。结果表明,确定了优化工艺条件为700~800℃下煅烧15 min,加入质量分数1.0%的Ca O除磷。利用现有氯碱工业盐精制工艺对煅烧、除磷后的盐水进行了进一步精制,精制后各项指标均符合离子膜烧碱工业标准,使资源得到了循环利用。     

浊点萃取-比值导数光度法同时测定水中孔雀石绿和结晶紫

建立一种浊点萃取-比值导数光度法同时测定水样中孔雀石绿和结晶紫,测量波长分别为639,476 nm,线性范围都是1.0×10^-8-1.0×10^-6mol/L,检测限分别是3.93×10^-9,4.96×10^-9mol/L。相对标准偏差分别小于4.08%和4.31%。该方法应用于测定水样中痕量孔雀石绿和结晶紫,结果令人满意。     

低温焦化烟气脱硝催化剂制备与中试验证研究

为满足低温脱硝催化剂应用需求,优化脱硝催化剂配方,采用偏钛酸水热法成型工艺,实现了低温蜂窝体脱硝催化剂的中试和连续化工业生产,并完成5 000 m~3/h焦炉烟气脱硝中试性能验证。结果表明,催化剂产品具有较好的低温活性、强度、耐磨性以及成本优势,可分别满足300℃高硫含量(500×10~(-6))和250℃低硫(200×10~(-6))的高水(体积分数18%)烟气氮氧化物达标(250×10~(-6))和超低(75×10~(-6))排放要求,氨逃逸低于3×10~(-6),催化剂连续运行两周以上未见明显失活。270℃高硫含量(500×10~(-6))烟气连续运行一周发现催化剂存在缓慢失活现象,表征证明催化剂失活是由硫铵类物质覆盖催化剂表面造成的,失活催化剂可通过高温焙烧再生。     

4种新型氟碳表面活性剂

介绍了巨化集团技术中心最新开发的4种氟碳表面活性剂:3-三聚环氧六氟丙烷酰胺基丙基(2-亚硫酸) 乙基二甲基铵、3-三聚环氧六氟丙烷酰胺基丙基甜菜碱、8-3-9氟碳-碳氢柔桥混链双季铵、6-3_9氟碳柔桥混链双季铵。其临界胶束浓度CMC分别为1.14×10-4、1．12×10-3、4．93×10-4、2．78×10-4 mol／L,在临界胶束浓度时表面张力分别为19．0、22．0、20．9、22．7 mN／m,在质量分数0．1％时,表面张力分别为16．4、18．2、19．2、20．4 mN／m。分析了氟碳表面活性剂结构与性能的关系。     

焦炉气加氢催化剂及净化工艺的开发

介绍了适合于焦炉气加氢催化剂及净化工艺的研究实验结果,实验表明,JT-1及JT-8型加氢催化剂均可适用于含高浓度CO和CO2气氛下原料气的加氢净化,且净化度高,副反应小,并满足以焦炉气为原料的甲醇厂的原料净化要求,可将原料气中硫化物脱除至总硫体积分数<0.1×10-6。     

导向立体传质塔板在低温甲醇洗装置中开发应用

根据合成氨变换气脱硫塔扩产50%的要求,开发出一种导向立体传质塔板(CTST-8)。对导向立体传质塔板的流体力学性能研究表明,新塔板具有板压降低、气液二相通量大、抗堵塞、能消泡等技术特点。对扩产50%的低温甲醇洗脱硫塔内的水力学参数进行了核算,结果表明,扩产后的操作参数均处于导向立体传质塔板正常操作范围之内。将导向立体传质塔板应用于山西天脊集团变换气脱硫塔的扩产改造,达到了扩产50%的要求,取得了良好的效果。塔顶出口气相中φ(H2S)≤2×10-6,φ(CH3OH)≤3×10-4,全塔阻力小于0.08 MPa。     

三头基型季铵盐表面活性剂的合成及表面性能研究

以甲胺醇溶液、环氧氯丙烷、十二胺、十六胺、十八胺为主要原料,合成出一种新型的表面活性剂BHMDn,(n=12,16,18,代表两端烷基链的碳原子个数),考察其的表面活性以及盐对其表面活性的影响。结果表明,目标产物水溶液的cmc分别为1×10-4,6×10-5,5×10-5 mol/L;临界胶束浓度下的表面张力rcmc分别为27.4,21.5,19.6 mN/m。目标物与十二烷基苯磺酸钠(SDBS)复配产生了较好的协同效应。     

负载MgO固体碱对氰乙酸乙酯脱酸精制性能研究

采用浸渍法制备出负载MgO固体碱吸附剂,利用差热-热重、X射线衍射、原子吸收光谱等方法对固体碱进行了表征,将固体碱用于氰乙酸乙酯吸附脱酸精制,考察了MgO负载量、焙烧温度对固体碱脱酸精制性能的影响,同时考察了再生后固体碱的脱酸性能。研究结果表明,负载MgO固体碱吸附剂能够有效脱除氰乙酸乙酯中的残留酸,当进料样品中酸度为58×10-6,精制后样品的酸度不大于5×10-6时,负载25%MgO固体碱脱酸精制后样品的处理量达到了200∶1(体积比),且精制后样品中金属Mg的含量不高于0.32×10-6,表明MgO具有良好的抗冲刷能力,再生后的固体碱仍具有较强的吸附脱酸能力。     

CLAY SEWER PIPE MANUFACTURE.—IV. THE INFLUENCE OF DIFFERENT SALT GLAZING TEMPERATURES UPON THE COLOR AND GLOSS OF GLAZES OBTAINED ON CLAYS WITH VARYING SILICA,ALUMINA, AND IRON OXIDE CONTENTS1

Object .—A study was made of the effects of different salt glazing temperatures upon the color and brightness of salt glazes produced upon clays with varying silica, alumina, and iron oxide contents. Results .—In tests conducted in commercial kilns operating under normal conditions, it was found that increasing the salt glazing temperatures has a tendency to produce duller and darker glazes on clays containing iron oxide. The brightness of the glazes produced may be approximately represented by the following formula: -1.00×₁+ 0.376×₂ - (1.885 + 0.385(1.01253)^(T-1110))×₃= 100G ×₁, ×₂ and ×₃ represent the percentages of silica, alumina and iron oxide, respectively. T is the salt glazing temperature in °C. When G was greater than 0, the glazes were bright; when between -0.1337 and 0 they were semi matt; and when less than -0.1337 they were matt. The color obtained may be approximately represented by the following formula: 10.3x₁ - 2.65x₂+ (14.6 + 54.1 (1.0066)^(T-1110))x₃= 100°C When C was between 0 and 2, white to tan glazes were produced; when between 2 and 3.5, light brown glazes were obtained; when between 3.5 and 4.75, brown glazes were produced; when between 4.75 and 8.2, mahogany colors were obtained; and when above 8.2, dark brown to black glazes were produced. Clays containing a high iron oxide content should be salt glazed at low temperatures while clays containing a low iron oxide content should be glazed at high temperatures to produce the best glazes. Decreasing the iron oxide and alumina contents will improve the brightness of the salt glazes. High alumina clays will produce darker colors than high silica clays with the same percentage of iron oxide.     

甲醇合成系统精脱硫技术改造总结

采用华烁科技公司的DJ-1多功能催化剂和EZ-3氧化锌脱硫剂对精脱硫系统进行技术改造后,系统出口总硫≤0.1×10-6,达到了设计要求,有效解决了合成塔入口气体硫含量超标严重的问题。     

Novel potentiometric sensors for the selective determination of domperidone

The fabrication and electrochemical response characteristics of two novel potentiometric sensors for the selective determination of domperidone (DOM) are described. The two fabricated sensors incorporate DOM–PTA (phosphotungstic acid) ion pair as the electroactive material. The sensors include a PVC membrane sensor and a carbon paste sensor. The sensors showed a linear, stable, and near Nernstian slope of 56.5 and 57.8 mV/decade for PVC membrane and carbon paste sensors, respectively over a relatively wide range of DOM concentration (1.0 × 10^?1–1.0 × 10^?5 and 1.0 × 10^?1–3.55 × 10^?6 M). The response time of DOM–PTA membrane sensor was less than 25 s and that in the case of carbon paste sensor was less than 20 s. A useful pH range of 4–6 was obtained for both types of sensors. A detection limit of 7.36 × 10^?5 M was obtained for PVC membrane sensor and 1.0 × 10^?6 M was obtained for carbon paste sensor. The proposed sensors showed very good selectivity to DOM in the presence of a large number of other interfering ions. The analytical application of the developed sensors in the determination of the drug in pharmaceutical formulations such as tablets was investigated. The results obtained are in good agreement with the values obtained by the standard method. The sensors were also applied for the determination of DOM in real samples such as urine by the standard addition method.     

MASS TRANSFER AND DIFFUSION COEFFICIENT DETERMINATION IN THE WET AND DRY SALTING OF MEAT

ABSTRACT

Dehydrated salted meat is widely used in Brazil as a very important source of animal protein. The main objective of this kind of processing is water removal. initially by osmotic pressure changes and then by drying, resulting in a product with intermediate moisture levels.

In this work, mass transfer and salt diffusion in pieces of meat submitted to wet and dry salting were studied. Slabs of beef m. trapezius with an infinite plate geometry were salted in a NaCl saturated solution or in a dry salt bed, at two temperatures (10 and 20°C) and different time exposures (120 min and 96 hours). Equilibration studies were extended up to six days.

It was observed that water loss increased with salt uptake, for increasing periods of times. At 20°C the moisture loss was higher than it was at 10°C in both salting processes. On the other hand, the kinetics of salt uptake and moisture loss were of greater importance in the process of dry salting than in that of wet salting.

The salt diffusion coefficient for wet salting was 0.26 × 10^?10m²/s at20°C and 0.25 × 10^?10 m²/s at 10°C and for the dry salting the values were 19.37 × 10^?10 m²/s at 20°C and 17.21 × 10^?10 m²/s at 10°C.