Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) - Volume 9, Issue 1, 2016

Background: In the energy-storage systems, supercapacitors have a wide range of applications in such as consumer electronics and hybrid electric vehicles because they are able to store and deliver energy at high rate. Nanocarbons and their composites have large specific surface area, high electronic conductivity and excellent chemical stability, promising for the electrode materials of supercapacitors. Methods: We briefly review the recent researches and advancements of supercapacitors based on nanocarbons and nanocarbon-composites. We also discussed the implications of their nanostructures on the performance of supercapacitor. Results: Based on the analysis of 127 references, this paper described the synthesis and electrochemical properties of nanocarbons and their composites such as N-doped carbons, carbon allotrope composites, metal oxides/graphene composites, sulfides/nanocarbon composites and conductive polymer/nanocarbon composites. Conclusion: Nanocarbons-based supercapacitors have good properties such as high specific capacitance and ultra fast charge-discharge rate. Because the nanostructured carbons of high quality are the key for high-performance of supercapacitors in particular, simple and bulk scale synthesis needs to stir up in the future. Exploitation of new and cheap nanocarbon-based materials with electrolyte ions accessible nanopore structures are highly recommended. On the other hand, problems from the morphology effects and aggregated nanostructures hinder the complete utilization of the nanostructures and must be solved in future work. Most importantly, understanding the relationship with nanopore structures and capacitance uptakes is urgent for the design of the practical supercapacitor device.

Background: According to the Guinness Book of Records, the earliest of allknown English patents for an invention was granted by King Henry VI in 1449 to Flemishborn John Utynam for making stained glass. The second patent was approved by King Edward VI and granted to Henry Smyth in 1552 for making Normandy glass. Objective: To show that most of the first published patents were related to the manufacture of glass or to instruments that used such knowledge. Method: We analyzed some historical documents and applied a brief statistical analysis on the number of glass patents publications. Results: In Italy, patent laws started as early as 1474 to protect incipient glass manufactures. The first French patent was granted in 1561 for a special lens dispositive (l'holmetre). The first American patent was issued in 1790 for an improvement “in the making of Potash and Pearl ash” - both are basically potassium carbonate, essential for the making glass and soap. The first German trademark registration, PERKEO, was granted in 1894 to a Berlin lamp producer. Approximately 827,643 patents with the term “glass” in the title or abstract have been filed worldwide, according to the European Patent Office (starting in 1859 and up to 2015). This number continues to grow as do total glass sales worldwide. Looking for the word “glass” in the title only, we found 250,589 patents filed in this period. Conclusion: We conclude that the spirit of innovation has in its origins a strong connection with the rise of glass technology.

Background: As the major product in international tea market, black tea accounted 75% of global tea trade in the world. China is the headstream of black tea as well as the major production country in the world. In recent years, the trend in consuming black tea has been rising, which gives big opportunity for the fast promotion and effective development in the black tea industry. Objective: To make a comparative study on the qualities of the black teas made by floral black tea technique and the traditional process technique. Methods: Four oolong cultivars were processed into black teas and their qualities were investigated. The qualities of floral black teas were assessed by means of sensory tests, physical and chemical analysis. The national standards (GB/T23776-2009) of China were followed for the sensory tests of the samples. Results: The black tea made by floral black tea technique had rich floral and fruity scents, tasted sweet, mellow, fresh and brisk, with obvious floral and fruity taste. Its fermentation of infused leaves was better than traditionally processed black tea. Conclusion: The quality of black tea processed from floral black tea technique was superior to the tea processed from traditional black tea technique. Floral black tea technique could greatly improve quality of black tea that processed from oolong cultivars.

Background: Zeolites have been widely applied in adsorption, separation, sensors and catalysis fields due to their uniform micropore structures, high surface areas and many other properties. However, their small micropores frequently cause molecular diffusion limitations, which impede their applications in many chemical reactions. Objective: To synthesize mesoporous zeolites via a hard templating route. Methods: Silicalite-1 with mesopores was prepared by using graphene oxide as a template. The structures and morphologies of samples were studied with X-ray powder diffraction, scanning electron microscopy and nitrogen adsorption/desorption at 77K. Results: The nitrogen adsorption results indicated the mesopores of 0.04 cm3/g were formed in silicalite-1, which were caused by graphene oxide nanosheets templating. The graphene oxide- templated zeolite had 1.5 times higher adsorption amount of methylene blue from aqueous solution than the conventional silicalite-1. Conclusion: Using graphene oxide as a template could add zeolites with mesopores corresponding to its removal by burning after synthesis.

NiS/reduced graphene oxide nanocomposites were prepared by a hydrothermal method. Electron microscope observation revealed that the materials were of thin sheet-like structure and X-ray diffraction indicated the NiS of high-purity on the graphene nanosheets. Nitrogen adsorption on the samples at 77 K revealed the porous properties. Such materials were pseudo-active, exhibiting high specific capacitance of 978 F g-1 at 1 A g-1 in 3M KOH and high capacitance retention of 76% over 1000 cycles at 5 A g-1, promising for applications in supercapacitors.

Objective: This work aims to use slow features extraction of time-varying signals to solve the unfavorable influences of traditional principal component analysis (PCA) method on feature extraction in Tennessee Eastman (TE) process. Methods: Slow feature principal component analysis (SFPCA) method can obtain the slow features information of the observed data while considering variance maximization. The monitoring statistical indices are built on SFPCA method, and their confidence limits are computed by kernel density estimation (KDE), respectively. Results: All the monitoring results of SFPCA are presented. The confidence limit for fault detection is set to 95%. The fault exists all the time from 161st sample by SFPCA method. Stochastic occurrence appears with relatively smaller amplitude in temperature of reactant feeding in fault 10. Monitoring chart based on SFPCA performs better with fault detection rate for T2 index reaching 93.13% and Q index 56.50%. In Table 2, the proposed method can detect most faults than PCA, especially for faults (4), (5), (8), (10), (11), (16), (17), (18), (19), (20), (21). In Table 3, for fault (2), (8), (10), (11), (13), (16), (17), (19), (21), SFPCA shows better detection performance than PCA. In fault 5, the positive step change in condenser cooling water temperature leads to a sharp increase in its flow rate which is measured by the 52nd variable. Conclusion: SFPCA method demonstrates better performance than the traditional PCA method from the perspective of both fault diagnosis rate and fault diagnosis time in TE process.