Why is the result of NH3-TPD almost similar for fresh and spent HZSM-5 catalyst?

Chlorinated organic formation in odor control scrubbers using hypochlorite?

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What solvent can I used for Paal Knorr reaction between 6-amino hexanoic acid and 2.5 hexanedione?

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How to polymerize TEOS?

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Ester cleavage conditions?

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How to quantify carbon deposition on CuZnAl catalyst?

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How to remove DCU and HOBT from my reaction?

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28 February 2021 2,153 1 View

What is the most common number of epitopes in an multi-epitope Vaccine?

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How to increase solubility of Poly acrylic acid in Dioxane solvent?

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Why is NH4OH added in heavy metals limit test?

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Is it efficient to do liquid biopsy to investigate the gene expressions of the tumor?

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Mohammad Reza Toosi

You must clarify which spent catalyst did you test (cracking unit, dehydration unit,...)? Moreover, you must find manufacturer of the spent zeolite to provide similar fresh one. Do TPO analysis or TGA to determine coking percentage and type of deposited carbon.

Xuemin Li

If you are sure that coking really happened, you may need to make sure that after the pretreatment, nothing was changed compared with the spent catalyst. I mean 350 oC may a little bit high for pretreatment.

Daniel Martinez

Maybe the pre treatment conditions have affected to the used material. Have you considered to analyze the used zeolite by TGA to measure the coke formation?