CIESC Journal

• 化工学报 • 上一篇    下一篇

用固定床吸附方法脫去液体蜡中的芳香烴

李荣模 ,殷行知 ,赵秀凤 ,袁亚英 ,吴惠锦   

  • 出版日期:1966-06-25 发布日期:1966-06-25

THE REMOVAL OF AROMATIC HYDROCARBONS FROM LIQUID PARAFFINS BY RECYCLE ADSORPTION IN FIXED BED

(Chemical Technology and Engineering)LI YUNG-MO, YIN HS ING-CHIH, CHAO HSIU-FENG, YUAN YA-YING, WU HUI-CHIN   

  • Online:1966-06-25 Published:1966-06-25

摘要: 用尿素脱蜡方法生产出来的液体蜡,一般都含有3~10%的芳香烃。欲将此蜡用来作为合成洗滌剂、石油酯增塑剂等轻化工产品的原料,就必须设法降低其中的芳香烃含量到允许范围。前阶段的工作表明,采用固定床循环吸附方法,脱除直馏煤油及其液体蜡中芳香烃是有工业化前途的。本工作就是在以往工作的基础上,进一步探索工艺条件和产品质量之间的初步规律,为中间放大试验提供了操作依据。 试验用原料油有两种:一种是成球法尿素脱蜡中型试验装置生产的液体蜡,馏程210~260℃,芳香烃含量3~5%;另一种是异丙醇尿素脱蜡工业试验装置生产的液体蜡,馏程210~260℃,芳香烃含量8~10%。吸附剂为青岛海洋化工厂生产的粗孔硅胶。隔带剂是90~120℃馏分的溶剂汽汕。脱附剂是工业苯。 试验结果表明,对于芳香烃含量为3~10%的液体蜡,采用固定床循环吸附方法脱去其中芳香烃的最惠工艺操作条件为:加料比(克原科/克硅胶)K=2.68~0.172C_0(C_0表示进料中的芳烃重量百分比);隔带剂和脱附剂用量,当以体积表示时,均为硅胶在床层中孔隙率的0.7~1.0倍,即1.0~1.5毫升/克硅胶。在最惠操作条件下,当控制去芳烃液体蜡产品中芳香烃含量小于1%时,回收率可达93~95%;副产品芳烃浓缩物纯度较高,折光率(n_D~(20))可控制在1.5000以上。

Abstract: The liquid paraffins obtained from urea-dewaxing process generally contain aromatic hydrocarbons in the range of 3~10%.When these paraffins are used for the manufacture of detergent or plasticizer, the content of aromatics must be reduced to a permissible level. Preliminary work has shown that a fixed bed recycle adsorption process appears to be a promising technique for the removal of aromatics from the straight-run kerosine and the liquid paraffins. In order to find out the relationship between the operation conditions and the product qualities and provide basic data for pilot plant experiments, a series of tests have been carried out. In the present tests, two kinds of feed were used. One was the liquid paraffin produced from the pilot plant of saturated aqueous urea solution dewaxing (in which the paraffin-urea complex is formed in spherical clusters), boiling range, 210~260℃,content of aromatics, 3~5% ,and the other was the liquid paraffin produced from the polit plant of isopropyl alcohol-urea dewaxing, boiling range, 210~260℃, content of aromatics, 8~10%. The adsorbent was the silica gel manufactured by the Hai Yang Chemical Works, Tsingtao, China. The liquid carrier was 90~120℃ naphtha. The desorbent was technical grade benzene. The results of the texts indicate that the optimum conditions for the liquid paraffins with 3~10% aromatics are as follows. Wt. of feed/Wt. of silica gel= 2.68 -0.172 C0 (C0= aromatics in the feed, wt. %). Volume of both liquid carrier and desorbent is 70~100% of the void volume of the silica gel bed, which is equivalent to 1.0~1.5ml./gr. of silica gel. Under these conditions, when the content of aromatics of the treated liquid paraffins is less than 1%, product recovery may be held at 93~95%. The purity of the by-product aromatic concentrates is relatively high and the refractive index (nD20) can be maintained above 1.5000.