Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) - Volume 13, Issue 1, 2020

Heavy metal pollution has pervaded many parts of the world, especially developing countries such as China. The discharge of wastewater containing heavy metals will cause soil pollution for a long time and harm to human health. Soil washing is an environmentally feasible and cost-effective approach for the clean-up of sites contaminated with heavy metals. As a relatively environmental protection agent, surfactants are widely used in soil washing. This paper generalized the methods of remediation of soil from heavy metals, expounded the mechanisms of soil washing by surfactant and the types of surfactants and summarized the application of different surfactants in washing heavy metals from soil. Finally, the application prospects and development trends of surfactant washing heavy metals from soil have been prospected.

Due to the presence of nitrides in oil, the stability, storage and transportation safety and deep processing of oil are affected. In recent years, denitrification of oil products has become one of the research hotspots for solving environmental pollution and energy shortages. Modified nanoparticles are important photocatalytic material because they have indicated improvement in the performance as compared with other technologies when they are used for denitrification. There are mainly three kinds of modified nanoparticles applied in the field of photocatalytic denitrification, including titanium catalyst, bismuth catalyst and others. The research on photocatalyst denitrification has been promoted by the advancement of science and technology. This article focuses on the development process, research status and catalytic mechanism of photocatalytic technology in the field of denitrification. In addition, it provides guidance for the preparation of novel modified nanophotocatalysts for high-efficiency applications in the field of denitrification of oils.

Background & Objective: Plastics are strong, light weight and durable due to which it has wide applications. Degradation of plastics is difficult due to their xenobiotic origin and recalcitrant nature. Hence, accumulation of plastics in the environment is posing an increasing ecological threat. Methods: Various methods are preferred for the reduction of plastics in the environment, of which degradation by chemical and biological means are considered to be more effective. In the biodegradation of plastics, micro organisms play a pivotal role. In the present work, microbial species are isolated from different sources such as cooking oil, grease and petroleum products. Two bacterial species such as Sphingomonas, Pseudomonas aeruginosa and three fungal species such as Aspergillus niger, Aspergillus flavus and one unidentified fungal species were isolated from the sources were used for the degradation of polyethylene plastic samples (black and white). Results: Sphingomonas indicated 56% (black) and 31% (white) degradation of polyethylene plastic. Unidentified fungal species also indicated 64% (black) and 45% (white) degradation of polyethylene plastic. During the degradation, pH altered from 7 to 8. SEM analysis indicated the presence of appreciable surface erosions, fading, cracks and extensive roughening of the surface with pit formation. Conclusion: Sequence analysis of Sphinogomonas species was done in comparison with the similar known bacterial species and the phylogenetic tree was generated based on the sequence analysis.

Background: Although many potential therapeutic compounds have been discovered and have exhibited a promising recovery, their effective delivery in the human system has always remained questionable with many pharmacological constraints in delivering them. Amidst all this, the concept of nanomedicine has always assured the potential to overcome the drug delivery complications in the present treatment methods. Losartan Potassium (LP) is indicated in the management of hypertension. Owing to its moderate bioavailability (32%) and a number of side effects due to the oral dosage forms of LP thus, nanoparticles based delivery would be beneficial. Objective: The present study is focused to develop a nanoparticle system of Losartan Potassium, an Angiotensin II receptor antagonist and a well-known promising antihypertensive drug, to conquer its limitation of bioavailability and potential adverse effects. ods: LP Loaded Polymeric Nanoparticles (LP-NPs) were developed by ionic gelation method using Chitosan (CH) and Tripolyphosphate (TPP) for cross linkage in various optimising ratios. After the successful optimisation and synthesis of LP-NPs, the optimised formulation was further characterized by Particle Size Analysis (PSA), Polydispersity Index (PDI), Zeta Potential (ZP), TEM analysis with the in vitro cytotoxicity and permeability evaluation. Results: The results showed the average size of 123.5 ± 1.23nm with polydispersibility score of 0.257 ± 0.079 and charge of -2.74 mV respectively. Further, Transmission Electron Microscopy (TEM) images showed the size range in almost conformity with DLS findings, representing the spherical and smooth morphology. In vitro drug release kinetics estimation showed sustained release routine of the drug and the cell viability studies done on Jurkat cell line displayed lesser cytotoxicity of LP-NPs (99.3 ± 2.28% and 98.17 ± 1.86%) in comparison with the LP only (85.3 ± 2.1% and 71.7 ± 1.07%) at different time periods (12 hours and 24 hours). Conclusion: The aforementioned results confirm the effective fabrication of LP-NPs and indicate that it may further, used on higher model systems to investigate the above parameters and their enhanced effectiveness in hypertension.

Background: Large amounts of oily wastewater and its derivatives are discharged annually from several industries to the environment. Objective: The present study aims to investigate the ability to remove oil content and turbidity from real oily wastewater discharged from the wet oil's unit (West Qurna 1-Crude Oil Location/ Basra-Iraq) by using an innovated electrocoagulation reactor containing concentric aluminum tubes in a monopolar mode. Methods: The influences of the operational variables (current density (1.77-7.07 mA/cm2) and electrolysis time (10-40 min)) were studied using response surface methodology (RSM) and Minitab-17 statistical program. The agitation speed was taken as 200 rpm. Energy and electrodes consumption had been studied and modeled. Results: The results revealed the positive effect of the electrodes design on the studied responses. Conclusion: Under the optimum values of the operating variables (5.675 mA/cm2, 40 min), 85.982% and 84.439% removal efficiencies of oil content and turbidity respectively were obtained and the consumption of energy and electrodes were observed as 4.333kWh/m3 and 0.36 g respectively.

Background and Objective: The objectives of this study were to investigate the effects of land use and land cover transitions on soil physico-chemical properties, and to comparatively study soil microbial activity in ecological restoration red soil region of subtropical southern China. Methods: A field experiment was conducted in a natural forest, four ecological restoration forests and an adjacent farmland. Based on the stable carbon isotopes of SOM, the δ13C values data confirm the 6 sites for soil sampling in this study were the ideal location for studying land cover transitions. The data showed that the soil physical, chemical and biological properties under the natural forest were significantly healthier than under cultivation. During forest re-growth on farmland, the ecological restoration time were 34, 26, 15 and 10a, respectively, and the SOM content, C/N, soil colony counts, soil basal respiration and soil enzyme activities significantly increased and approached values of virgin forest. Results & Conclusion: In general, the SOM content and soil microbial activities in ecological restoration forest were usually intermediate between the natural forest and farmland, and there was significant (P< 0.05) difference between forest and farmland. The results indicated that, because of appropriate climatic conditions of red soil subtropical southern China, the dynamic balance of soil ecosystems can be reconstructed and restored in several years or decades.

Background: Reusing waste water by appropriate treatment is an effective method for substantiating the ever increasing water demand for construction, irrigation, domestic and industrial purposes. The greywater is the domestic waste water that does not contain the toilet effluent and it is converted and used for non-potable purpose through coagulation and flocculation by using natural coagulant. Objective: The main objective of this work is to evaluate the coagulating efficiencies of various natural coagulants on synthetic greywater by varying pH, mixing speed, mixing time and coagulant dosage. Methods: Powdered coagulants obtained from tamarind seeds, moringa oleifera, banana peels and fly ash were compared with conventional commercial coagulants like alum for synthetic and real greywater. Results: The natural coagulants have shown significant performance compared to chemicals like alum. Conclusion: The turbidity removal efficiency for tamarind seeds, moringa oleifera, banana peels and fly ash were found to be 61.33%, 85.75%, 90.42%, 94.27% against 96.49% obtained from alum on treating with synthetic grey water under identical conditions.