How to refine Silver - The Complete Silver Chloride Process Tutorial

hi everybody in this video i'm going to show you how to turn this old sterling silver scrap into this fine shiny silver by refining it through the silver chloride method before we continue don't forget to click the subscribe button and hit the notification bell but first a word of caution the process shown in this video is for recreational purposes only any attempt to repeat the process requires the use of all safety gear and equipment such as heat proof shielding goggles a fume hood and gloves here have about 500 grams of old sterling silver jewelry the first step in preparing the scrap is to incinerate it preferably in a stainless steel pan remember good ventilation is needed here as some organic residues may catch fire and get real smoky while we are burning let's talk about why you would want to consider using the silver chloride method there are two main benefits for taking the silver chloride route first it's relatively easy to set up and there's no complicated equipment involved second this process can produce high purity silver 99.9 percent and even higher the downside of this process is that there are quite a bit of washing cycles that produce a large amount of waste solution however this waste solution can be used in other processes or easily neutralized and disposed of for the digestion process i'll be using a round bottom narrow neck boiling flask a proper reactor would probably be a better choice here but to be honest it is just too expensive i wouldn't mind spending a few more minutes cutting the scrap to size to fit through the narrow flask neck another alternative would be to melt the scrap silver and produce grains click up here to see how to do that now before assembling the rest of the glass i add boiling hot distilled water to the scrap and the flask is set on a hot plate at medium heat okay now let's go over the setup here's the flask with the scrap covered with hot distilled water above it there's a joint adapter attached to it are a spiral condenser and an addition funnel and here's the fume out tube going to the fume hood to begin the dissolution of the scrap concentrated nitric acid is added to the addition funnel and slowly allowed to drip over the course of a half an hour it is important not to overdo the nitric adding too much at once will cause a nasty boil over the reason for choosing a closed system rather than just using a simple open mouth flask is to minimize nitric acid consumption you can read more about it in the full tutorial on the golden scrap website you can click right here or see the link in the description below and we're done we'll let it cool back down all right here's the solution after cooling and settling for a few hours the solution is now ready for filtration i'll use a simple gravity filtration with fluted filter paper this type of folding is very simple to make and provides a larger surface area for the liquid to pass through first only the supernatant is filtered as it is free of solid particles and will run down the filter very fast once the supernatant has passed through the filter the sludge is drained and washed several times with distilled water to collect every drop of silver solution now that the silver nitrate solution is clear of any solids it is placed on a magnetic stirrer and now begin adding a saturated solution of the calculated amount of sodium chloride silver chloride looks like cottage cheese and will precipitate immediately as you can see some nitrogen dioxide fumes are formed because of the reaction between free nitric acid and chloride ions i'll keep adding the entire amount of sodium chloride solution until there's no more production of a white precipitate since the silver chloride sludge is quite thick and heavy it was a bit tough for my magnetic stirrer and i really should have used my overhead stirring unit i'll stir things up for a couple more minutes or so to make sure all of the silver has been precipitated when that's done it is left to settle all right now we get to the most critical part of the process the washings the number of washings at this step of the process will determine the purity of the silver simple as that the more you wash it the better washing the silver chloride is done by covering the sludge with as much hot water as possible stirring it for a couple of minutes allowing it to settle siphoning the liquid and starting all over again until the wash water is nearly colorless about eight to ten washes with a copious amount of boiling hot water are usually enough to achieve very pure silver now that the wash water is clean enough the next step is to convert the silver chloride to silver oxide by using sodium hydroxide to clearly demonstrate the reaction i'm adding sodium hydroxide to the silver chloride sludge the reaction is relatively fast and vigorous and you can see the dark silver oxide powder in contrast to the pure white silver chloride sludge is covered with water and stirred and the calculated amount of sodium hydroxide is added slowly to make sure all of the silver chloride will be converted to silver oxide this mix needs to be violently stirred for at least 20 minutes here i'm doing a smear test no not the smear test you think i'm basically using a spoon to smear the silver oxide powder against the wall of the glass if white streaks appear it means that the conversion was not complete and more sodium hydroxide and stirring are needed here's a failed smear test all right it seems like the test is successful and there's no more silver chloride it's time to reduce the silver oxide back to metallic silver powder this is done by slowly adding glucose to the mix this simple sugar is very efficient at reducing silver oxide and a little goes a long way as the reduction begins you can immediately see a change in the color of both the solution and the powder the silver will slowly plate a shiny mirror on top of the beaker wall and the solution will get very hot a clear indication the reduction is complete is the silver powder settles very fast and no more reaction is happening upon adding glucose to the solution once the reduction is complete the silver powder is washed several times with hot water exactly in the same manner as the silver chloride was washed these washes will remove all of the remaining sodium chloride sodium hydroxide and glucose solution so that a very clean melt can be achieved the resulting silver powder should have a very light gray whitish color the color is a good indication of purity the pure silver powder is transferred to a shallow and wide dish to dry thoroughly on low heat our silver powder is out of the oven and is ready for meltdown let's melt a small sample to see how our silver turned out if you haven't already make sure you leave us a thumbs up click that subscribe button and hit the notification bell [Music] hmm that's one shiny piece of pure silver [Music]

Channel: indeedItdoes

Views: 56,011

Keywords: silver refining, Precious Metals, silver chloride, silver recovery, silver 999, silver chloride to silver metal, silver refining process, silver refining electrolysis, Precious Metals Refining, Precious Metals from electronics, Precious Metals Rcovery, silver refining nitric acid, silver crystal, silver bar, gold and silver, platinum, palladium, sillver price, Precious Metals price, gold-n-scrap, scrap metals, scrap silver, Extracing silver from scrap, चांदी शोधन

Id: ZDsbtuvnSQM

Length: 10min 32sec (632 seconds)

Published: Sun Feb 06 2022