Preparation of MoB2 Nanoparticles by Electrolysis of MoS2/B Mixture in Molten NaCl-KCl at 700 oC

MoB2 is synthesized by the electrochemical reduction of solid MoS2/B mixture in molten NaCl-KCl at 700 oC. Unlike the traditional methods, the electrolysis method employs the low-cost MoS2 feedstock and the boronization reaction happens at a low temperature of 700 oC. The electrochemically induced boronization involves two steps: the electrochemical desulfurization to generate Mo and the reaction of Mo with B to form MoB2. The S2- released from the reduction of MoS2 transfers to the carbon anode and is oxidized to sulfur gas, realizing a green synthetic process. In addition, the influences of molar ratio of MoS2 and amorphous boron and electrolysis cell voltage on the phase composition and morphology of electrolytic products were studied. The obtained MoB2 particles possess a uniform nodular morphology. Overall, this paper provides a straightforward and green process to prepare MoB2 nanoparticles using economically affordable raw materials at low temperature, and this method can be extended to prepare other borides.

Alcohol and pH Detectors Based Internet of Thing for Hand Sanitizer

<p align="justify"><strong><em>Alcohol and pH levels in hand sanitizer are two things that need to be considered. The amount of alcohol content affects the level of effectiveness in killing germs, while the pH level is a factor that indicates whether the liquid is safe for human skin or not. HANDSIOT is a device to measure alcohol levels and pH in hand sanitizers. HANDSIOT is operated by testing the hand sanitizer liquid in the liquid container at the bottom. This device is made to be able to take measurements effectively and can monitor the measurement results in real-time using a smartphone. Gas chromatography and electrolysis methods were implemented using the MQ-3 gas sensor and the SEN0161 pH sensor. The gas chromatography method is used as a method of measuring alcohol content based on the evaporation of the alcohol. While the electrolysis method is used to measure the pH degree by measuring the amount of current flowing using two electrodes. In testing the accuracy of this tool by comparing the readings on the tool with an alcohol meter and also a pH sensor that is already available on the market</em></strong><strong></strong></p>

Removal of Heavy Metal Mercury (Hg) Liquid Waste through Electrolysis Method in Paya Ateuk Village, Pasie Raja District, South Aceh

Electrolysis is one of the methods used to remove heavy metal mercury (Hg). The electrolysis process is carried out on residual liquid waste from gold processing by utilizing chemical reactions through electrodes immersed in an electrolyte solution. This research method is experimental. We conducted laboratory tests to see the electrolysis process on the residual liquid waste from gold processing in a 10-liter container. We took samples from 10 different containers, 1 liter each from each tub. Sampling time was carried out in the morning, afternoon, and evening. The results showed a significant decrease in mercury (Hg) levels up to 1.30% with 12 volts of electricity for 100 minutes. In contrast, the lowest decrease occurred in the electric current of 3.3 volts within 25 minutes. We use the electrolysis method. This heavy metal removal technique can be applied and managed properly by the community and local government to minimize heavy metal pollution such as mercury in the surrounding environment due to waste from the community's traditional gold processing.

The Effect of Variations in Electrolyte Temperature and Current Strength on the Synthesis of Manganese Dioxide from Manganese Sulfate Precursors by Electrolysis Method

The development of science and technology today in the field of electronics, especially energy storage increases the demand for the use of lithium secondary batteries. The development of lithium batteries is focused on energy storage capacity by using manganese dioxide (MnO2) as a lithium battery cathode material. Manganese dioxide was chosen as the cathode material for lithium batteries because it has a high storage capacity of about 615 mAh/g compared to other materials such as graphite which has a storage capacity of 372 mAh/g and has a low toxicity of 0.14 mg/kg. MnO2 was synthesized by electrolysis method from manganese sulfate (MnSO4) precursor which was obtained from Trenggalek manganese ore leaching process. The electrolysis process was carried out for 5 hours using variations in electrolyte temperature of 30, 40, 50 and 60oC as well as variations in current strength of 2, 3, 4 and 5 A to determine the effect of electrolyte temperature and current strength on mass gain, structural polymorphy and morphology of MnO2 formed. The highest mass gain was obtained at the use of an electrolyte temperature of 60oC and a current of 5 A, which was 11.4 grams with the polymorphy structure of the MnO2 compound formed was α-MnO2 polymorphy. SEM image shows that the MnO2 particles have a spiny round shape and tend to agglomerate with particle diameter values ranging from 50 nm - 170 nm. Keywords: Electrolysis, MnO2, MnSO4, Electrolyte temperature, Current strength

TREATMENT OF TRADITIONAL ETHANOL FERMENTATION WASTE WITH ELECTROLYSIS METHOD FOR DECREASING COD AND SULFIDE

Ethanol is produced from molasses by a fermentation process. In Bekonang, ethanol manufacturingby a home-scale industry so the waste just thrown away in free water then pollution occurs both in rivers and in paddy fields. Ethanol waste has very high chemical oxygen demand (COD) and contain high sulfide. Electrolysis that use for reduce leves COD dan Sulfide with electricity as main source for direct current flowing electricity (dc) to the anode and cathode. Electrolysis time 10, 15, 20, 25 and 30 minutes and voltage variation 5, 10 and 15 volt. Based on data obtained in the test COD obtained optimum levels of 284.5 mg/L from the initial content of 586 mg/L , at a time variation of 30 minutes and voltage 15 volt. The sulfide test obtained optimum levels of 0.0661 mg/L from the initial content of 0.305 mg/L, at time variation of 25 minutes and a voltage of 15 volt.

RESULTS OF RESEARCH ON THE APPLICATION OF THE ANNEALING PROCESS TO INCREASE THE RESOURCE OF THE SHIELD IN HIGH PRESSURE VALVES

As a result of analyzing the causes of defects in high-pressure valves, it was found that gate and seat failures are dominant. From this point of view, it is important to increase the service life of the parts included in this pair. The article discusses the implementation of the iron process and the results obtained in order to increase the resource of the gate-seat pair of high-pressure gate valves. It turned out that the coating of the gate's working surface by the iron-iron method allows, along with an increase in corrosion resistance (by 1.5-1.7 times), creates a serious basis for increasing the service life by 75-80%. Keywords: iron process, electrolysis method, gate, service life.