Precipitate in developer

I mixed up a batch of D23 and found not all the chemical seems to have disolved. I thought I would make it in a more concentrated form this time. Instead of 1000ml I made 500ml of solution. It fits better in the 500ml bottle I have. I then would compensate when mixing for using.

D23 uses 100g Sodium Sulfite and 7.5g metol

The temperature of the distilled water after it was heated in a microwave was ~144F. Solution was clear after mixing, more distilled water was added to bring the final solution up to 500ml. It cooled down and now has a suspended chemical in it. I assume it is the Sodium Sulfite. I assume this will disolve when I go to mix it full strength. Is this correct? Does mixing the chemicals at high tempuratures, say above 125F, cause any breakdown so that it doesn't work as expected?

MIxing it at a high temp in not enough water makes a super saturated solution, and when it cools it can't hold the dissolved chemicals. DO NOT USE IT AS IS. Heat it back up and add another 500ml of hot water to redissolve the precipitate. then fill two 500ml bottles, let it cool down and it is now ready to use.

Excellent answer.

Thanks,

If you like D-23 try Zonal pros' gamma plus at 1:20.

I never participate in developers, especially not ones with precipitate in them. Thread title edited.

Regards,

the Spelling Nazi

Thanks Ole. I wanted to say something similar, but was hesitant.

I usually correct spelling and grammar errors in thread titles silently, but this one was too good to change.

Rlibersky said:

The temperature of the distilled water after it was heated in a microwave was ~144F......Does mixing the chemicals at high tempuratures, say above 125F, cause any breakdown so that it doesn't work as expected?

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I have read that water should not be above 125 degrees F (52 degrees C) as above this temp, Metol decomposes.

Dassonville D3 paper developer (w/glycin) always has a crystalline precipitate at the bottom of the container when stored as a stock solution, but this dissolves easily when diluted further and heated to 125°F. The working solution seems to have a long shelf life (at least 1 year) in brown glass bottles, with no precipitate.

Rlibersky said:

I mixed up a batch of D23 and found not all the chemical seems to have disolved.

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The precipitate can also be calcium salts from the tap water. Add some EDTA to the water before adding other chemicals. Cleveland tap water - lake surface water - can be treated with 1/4 tsp / liter. The problem varies with season and phase of the moon.

Would there be any harm in leaving the solution in this state until use?