Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) - Volume 7, Issue 2, 2014

In recent years, nanosilicas have received particular attention in the use as filler for reinforcing silicone rubber. They can be homogeneously distributed within the polymer matrix and improve the physical and mechanical properties of silicone rubber, e.g. the tensile strength, tear strength, modulus and abrasion resistance. The enhanced performance in mechanical and thermal aspects is primarily attributed to the formation of the strong interfacial interactions between nanosilica filler and rubber matrix. Many methods for the surface chemical modification of nanosilica are developed to enhance its dispersion and compatibility in silicone rubber by changing its surface from hydrophilic to hydrophobic nature. We briefly summarized recent literatures on the techniques of the surface chemical modification of nanosilica for use in reinforcement of silicone rubber.

Scale deposition is a difficulty encountered with water containing ions of sparingly soluble salts. A widely used technique for controlling scale deposition is by dosage of an antiscalant. Large quantities of polymeric scale inhibitors are used for scale control in cooling water systems, water desalination processes and oil field operations. This paper summarizes kinds of scale inhibitors, such as natural polymer inhibitors, carboxylic acid polymer scale inhibitor, sulfonic acid polymer scale inhibitor, phosphorus-containing polymer scale inhibitor, environmental-friendly scale inhibitor and reviewed patents on scale inhibition technology. Environmental-friendly scale inhibitor is not only the most promising green scale inhibitors, but also the main goal of future research and development.

Zirconia nanocrystals are the best materials to combine with various resins into a transparent high-index composite. Such composite is crucial for the manipulation or enhancement of light in devices such as Organic-Light-Emitting-Diode (OLED) or Liquid- Crystal-Displays (LCD) that surrounds us today. To make a transparent composite, the nanocrystals have to be small (<10nm), un-agglomerated and fully dispersed in resins. They must also be crystalline to provide a better refractive index. Furthermore, since the index of a composite is determined by the volume fraction of the constituents, a substantial increase can only be achieved with a high zirconia loading, usually more than 50wt%. Consequently, the price of zirconia nanocrystals should not be too expensive compared to that of common resins. This requirement excludes many synthesis methods reported in the scientific literatures that employ delicate chemicals or require elaborate procedures. On the other hand, many simpler and large-scale processes for the production of dispersible zirconia nanocrystals have been patented by different companies. A review of the latest development is presented in this paper. Focus is placed particularly on the size, crystalline phase and the dispersibility of the products, as well as on their associated cost.

The development of photosensitive glass (PG) has a remarkable history since its first commercial discovery in the 1940s. The manufacturing of PG is one of the most widely reported methods for special glass manufacturing. PGs are capable of forming permanent photographic images when subjected to light, providing security, high quality and productivity. The first U. S. patent about photosensitive glass was filed on December 8th, 1943, and published July 18th, 1950, by Stanley Donald Stookey. A historical perspective about photosensitive glass represents an important step for future applications. PG has been considered one of the most interesting research areas with potential industrial applications. A number of companies and institutions have explored the usefulness of such special glasses. In this paper, we investigated the number of published manuscripts and patents and determined the correlation of research activities to the production of new PG materials. The United States, Japan and China have been leaders in photosensitive glass development and have contributed to an impressive rise of activity in PG based on a number of new publications, author keywords, affiliations and primary characterization techniques. We verified that the number of published fundamental PG studies was greater from academic institutions than from industrial laboratories. According to the European Patent Office, more than 6,228 patents have been globally filed prior to 2013 with the terms “photosensitive” and “glass” within the title or abstract. These numbers have continued to grow along with worldwide PG-related sales. Based on the Scopus database, for the same period, 1,301 PG documents (primarily manuscripts) were published with the same terms in the title, abstract or keyword list. Statistically, there have been fewer worldwide publications of manuscripts than patents.

To investigate potential sources of the natural antioxidants from fruits, Terminalia catappa, Carissa carandas, and Opuntia ficus indica, have been selected for this study. Their total phenolic content (TPC) and antioxidant activity (AOA) were determined by using DPPH (2,2-diphenyl-1- picrylhydrazyl), ferric reducing power (FRP) and chelating effect methods. Data obtained show that among these species, the highest polyphenolic contents were found in T. catappa (1005 mg/100g GAE) with the highest AOA (49 to 79%), whereas, the least TPC was found in O. ficus indica (200 mg/100g GAE) having AOA (18 to 52%) . However, C. carandas fruit showed moderate polyphenolic content (410 mg/100g GAE) with a significant antioxidant activity (22-64%). On the basis of these results, it has been concluded that antioxidant activity is concentration dependent and TPC of fruits is directly proportional to the antioxidant activities determined by different methods.

Sewage sludge is the material which is generated upon conventional wastewater treatment processes and it is must be treated to reduce the hazards and environmental impact. Wet oxidation (WO) is applied to treat industrial and municipal sewage sludge (3000- 6000mg/L total organic carbon). Experiments were carried out to investigate the effects of temperature, H2O2 excess (HE), the initial TOC, residence time and concentration of catalyst on oxidation of the municipal sewage sludge. The results showed that greater than 90% TOC removal from sewage sludge was achieved using catalytic wet oxidation (CWO). Homogenous catalyst, FeSO4 and CuSO4 showed effective removal for sewage sludge. It was concluded that CWO was an effective process for removing organic compounds from sewage sludge.

This study was conducted to identify and compare natural antioxidant based plant sources. Polyphenols are the main constituents of the natural antioxidants obtained from fruits, leaves, and seeds etc. In this work, four types of seeds from Trachyspermum ammi (Ajwain), Brassica alba (Mustard), Trigonella foenum graecum (Fenugreek) and Papaver somniferum (Poppy) were selected and their extracts were tested for antioxidant activity (AOA) by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and chelating methods. Total phenolic contents were found in the range of 1015-6900 mg/100 g (p<0.5). Antioxidant activity by DPPH radical scavenging and chelating methods was found to be in the range of 44-95% and 33-77% (p<0.5), respectively. This study revealed that T.ammi is a potent source of natural antioxidant and can be used to replace synthetic antioxidant. However mustard, fenugreek and poppy have also proved to be the potential sources of phenolics.