Environmental pollution and global warming cause serious problems in human life. Since the demand for our human daily appliances had been increased by years, the organic chemical-based industries response that demand increment by increasing their production process. Because of that, the environmental pollution becomes worse and worse. Green chemistry thus was introduced to influence the chemical industries to strive for better environmental sustainability. Over 20 years, green chemistry principles have to influence the organic chemistry field especially as many researchers have put their attention on that field of research. So far, synthesis process involving organic compounds has been considered on waste prevention, safer solvents, design for high energy efficiency, and usage of renewable feedstocks. This review comprehensively discusses in brief about the implementation of green chemistry principle and their applications in the synthesis process of organic compounds.

The development of science and technology is accompanied by a complex composition of multiple pollutants. Conventional passive separation processes are not sufficient for current industrial applications. The advent of active or responsive separation methods has become highly essential for future applications. In this work, we demonstrate the preparation of a smart electrically responsive membrane, a poly­(vinylidene difluoride) (PVDF)–graphene composite membrane. The high graphene content induces the self-assembly of PVDF with a high β-phase content, which displays a unique self-piezoelectric property. Additionally, the membrane exhibits excellent electrical conductivity and unique capacitive properties, and the resultant nanochannels in the membrane can be reversibly adjusted by external voltage applications, resulting in the tailored gas selectivity of a single membrane. After the application of voltage to the membrane, the permeability and selectivity toward carbon dioxide increase simultaneously. Moreover, atomic-level positron annihilation spectroscopic studies reveal the piezoelectric effect on the free volume of the membrane, which helps us to formulate a gas permeation mechanism for the electrically responsive membrane. Overall, the novel active membrane separation process proposed in this work opens new avenues for the development of a new generation of responsive membranes.

A synthesis and kinetic study of the urea controlled-release composite material based on isolated Na-lignosulfonate, Na-alginate and tapioca was carried out. This experiment’s aims were to isolate Na-lignosulfonate from wood sawdust and to applicate this isolated Na-lignosulfonate, along with tapioca and Na-alginate as urea control release composite material. A kinetic study of urea released from the composite materials was also conducted. Na-lignosulfonate was isolated by Kraft lignin method to give a brown solid yield of 16.92% and was characterized by FT-IR spectrophotometer and SEM-EDX. The composite materials were synthesized by blending urea as the active compound with composite material as the carrier compound. Three types of material were prepared: complete material (A), low-concentration Na-lignosulfonate material (B) and material without tapioca (C). The composite material had a spherical form with 0.79 mm radius and 2.16 mm swollen radius. Urea content inside material was 40.425 mg urea/g material. The urea diffusivity coefficient for material A, B, and C were 7.27 x 10–6; 15.50 x 10–6 and 0.94 x 10–6 m2 h–1, respectively. Modelling analysis showed the experiment obeyed around only 15% of the Korsmeyer–Peppas model, but there was good correlation (80%) with the unsteady-state diffusion model.

By miniaturizing the reactor dimension, microfluidic devices are attracting world attention and starting the microfluidic era, especially in the chemistry field because they offer great advantages such as rapid processes, small amount of the required reagents, low risk, ease and accurate control, portable and possibility of online monitoring. Because of that, microfluidic devices have been massively investigated and applied for the real application of human life. This review summarizes the up-to-date microfluidic research works including continuous-flow, droplet-based, open-system, paper-based and digital microfluidic devices. The brief fabrication technique of those microfluidic devices, as well as their potential application for particles separation, solvent extraction, nanoparticle fabrication, qualitative and quantitative analysis, environmental monitoring, drug delivery, biochemical assay and so on, are discussed. Recent perspectives of the microfluidics as a lab-on-chip or micro total analysis system device and organ-on-chip are also introduced.

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