The plasma electrolysis method using N2 and O2 injection is an effective and environmentally friendly solution for nitrogen fixation into nitrate and ammonia. The reaction pathway, the effect of the N2 and O2 gas injection composition are important parameters in understanding the mechanism and effectiveness of these processes. This study aims to determine the formation pathway of nitrate and ammonia by observing the formation and role of reactive species as well as intermediate compounds. Two reaction pathways of NOx and ammonia formation have been observed. The NOx compound formed in the solution was oxidized by •OH to NO2, followed by the production of a stable nitrate compound. The ammonium produced from the ammonia pathway was generated from nitrogen reacting with •H from H2O. The amount of NH3 formed was lesser compared to the NOx compounds in the liquid and gas phases. This indicates that the NOx pathway is more dominant than that of ammonia. The gas injection test with a ratio of N2/O2 = 79/21 was the most effective for nitrate formation compared to another ratio. The results of the emission intensity measurement test show that the reactive species •N, •N2*,•N2 + , •OH, and •O have a significant role in the nitrate formation through the NOx pathway, while the reactive species •N and •H lead to the formation of NH3. The highest nitrate product was obtained at a ratio of N2/O2: 79/21 by 1889 mg L -1 , while the highest ammonia product reached 31.5 mg L -1 at 100% N2 injection.

Safe clean water, especially for consumption purposes, is needed by the humans. Various regulations on water safety standards have been developed and implemented by each country, including Indonesia Regulation of the Minister of Health Number 492/MENKES/PER/IV/2010 concerning Water Quality Requirements; SNI 01-3553 2006 on Drinking Water in Packaging and Government Regulation of the Republic of Indonesia Number 82/2001 on the Management of Water Quality and Control of Water Pollution. Some parameters of physics, chemistry, biology and radioactivity are the benchmarks of water security. Raw water treatment for clean water and drinking water has been done using oxidation and electromagnetic methods. Both of these methods have been tested in local water company (PDAM) at Bangka Barat which has problems with high organic content, the amount of heavy metal content Fe and Mn that exceeds the threshold above normal and high acidity level. Test results after processing show physical and chemical parameters that meet the criteria of water quality and drinking water requirements in accordance with regulations set by the government. Other important things besides meeting the health requirements are also the quality assurance of the measuring instrument used to test the physical and chemical parameters. This measurement traceable to International System of Units through Research Centre of Metrology-Indonesian Institute of Science.

Mining areas in Indonesia still use water sources from the pit lake, called Kolong. Kolong is raw water material of the water local company (PDAM) in obtaining clean water. The lake water usually processed with chemical and physicsmethods before distributed to the community. Whereas in fact the former mine lake water has a heavy metal content that is still relatively high. In mining areas, river and lake water are still polluted by heavy metals that harm living things that can not be decomposed directly by microorganisms naturally and even require a relatively long time to process them. Processed by using Advanced Oxidation Processes (AOPs) and Electromagnetic Water Treatment (EWT) become one of the processing alternatives by removing the heavy metals. The advantage of using this method is high efficiency, ability to process will not cause another waste andincluding as clean technology. The aim of this research activity is to test integrated water treatment system using the physical and chemical method by utilizing surface water contaminated by heavy metals through a combination of advanced oxidation technology and electromagnetic water treatment for physics-chemical water quality improvement which can be utilized by PDAM as raw water to get clean water. This research comparing no processing water, processing water with AOPs and EWT, then combining AOPs-EWT. The result of heavy metal removal in water can be reduced up to ± 90%.

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Wastes containing phenolic compounds, including 2-chlorophenol and 4-chlorophenol at a threshold exceeding 50 mg / L, are very harmful to the environment. The processing of waste containing phenolic compounds using ozone and plasma technology is therefore an environmentally friendly and relatively inexpensive solution. The processing carried out in this study uses ozone plasma technology. Plasma is generated by high voltage transformator, which is fed into electrodes wound on a reactor made of quartz glass. The reactor type is dielectric barrier discharge (DBD) have the ability to degrade these waste, by producing reactive oxygen species, including •OH, •O2and molecular species of O3, H2O2. Subsequently, active species with high energy are transferred to the liquid phase, to react with chlorophenol compounds. According to the results, the dielectric barrier discharge plasma reactor using electrode coils was able to degrade waste containing 2chlorophenol compounds by 70.96% and 79.41%, in acidic and alkaline conditions, respectively, while, 4-chlorophenol was degraded by 23.42% and 53.54%, in acidic and alkaline conditions, respectively.