Cyanoethyl derivatives and sulfoxides have good solvent properties for aromatics. Ternary systems of different groupings have been investigated. These include thio-dipropionitrile and oxy-dipropionitrile; alkanes, cyclanes, olefines, cycloolefines; and monocyclic and bicyclic aromatics. Ternary system with dimethyl sulfoxide was also studied. In liquid-liquid extraction, compromise has always to be made between selectivity and solubility. A method for the choice of solvents was presented. The results indicate that the order of adaptability is dimethyl sulfoxide> oxy-dipropionitrile> thio-propionitrile.

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.

The molecular weight distribution of cis-1,4 polybutadiene obtained by polymerization with homogeneous Ziegler catalyst (Et2AlCl-CoCl2-4C5H5N) as well as heterogeneous Ziegler catalyst (i-Bu3Al-Til4) has been determined by means of fractional precipitation. The results show that the molecular weight distribution of both types of polybutadiene is not broad. With regard to the homogeneous catalytic system, the molecular weight distribution becomes narrower when the temperature of polymerization is increased, the monomer concentration lowered, the chain transfer agent added and the cobalt concentration decreased or the Al/Co ratio increased. As to the heterogeneous catalytic system, the homogeneity of molecular weight distribution increases with the lowering of the polymerization temperature and the decreasing of the Al/Ti ratio. But the monomer concentration and aging of catalyst give no evident effect. Molecular weight distribution obtained with heterogeneous catalytic system is narrower than that obtained with homogeneous catalytic system. The peak of differential distribution curve of the former lies on higher molecular weight side, while that of the latter on lower molecular weight side. This is probably due to the fact that the chain terminating rate in the heterogeneous catalytic system depends upon chain length, while that in the homogeneous catalytic system is independent.

Based on a proposed model for the flow of solid particles through an orifice, the authors have derived the following equation for the solids discharge rate with and without pressure drop, The above equation correlates 206 experimental data of five different authors with an average deviation of 18%.

For an incompressible fluid flowing in a line of pipes and pumps in series, Bernoullis equation can be effectively applied to solve any particular flow problem. When the pipe system consists of a number of complicated branches and cycles, a systematic method for the analysis of the flow system is yet in need. In this article, by transforming the general formula of the pressure drop in pipes into the form, of linear element with respect to flow rate, and further, by introducing the idea of a "complete stream", a set of simultaneous linear equations can be obtained. Such equations can then be represented in the form of matrix, which, besides presenting the equations in a regular form, also makes possible the solution by using digital computers.