Ryan O’Donnell, 37, stored the substances, including potassium nitrate, nitrogen and sulphur, at his Edinburgh home.
A rocket diagram plan was discovered alongside notebooks which contained handwritten instructions that would allow an individual to prepare viable, high explosive substances.
Details on how to make a homemade firework were also found alongside a Kinder egg containing a low explosive substance.
O’Donnell was sentenced at the High Court in Edinburgh on 12 February 2025 after pleading guilty to offences connected to homemade explosives.
He also admitted possessing almost 1500 indecent images of children and has been placed on the Sex Offenders Register for 10 years.
He will be supervised by the authorities for 12 months following his release from custody.
Moira Orr, who leads on major crime for the Crown Office and Procurator Fiscal Service (COPFS), said: “The substances that Ryan O’Donnell had in his possession could have been used to manufacture improvised explosive devices.
“They would have had the potential to cause significant harm to individuals and damage to property if used for criminal purposes.
“This case also demonstrates our commitment to prosecuting sexual offenders, using every tool at our disposal to secure justice.
“We have a duty to keep the people of Scotland safe from harm and working with police, government and other agencies, we are committed to ensuring that those involved in this type of offending are brought to justice.”
The court heard how police officers discovered the items following a search of O’Donnell’s Dumbiedykes flat and Loanhead garage in April 2024.
Altogether, 1.7kg of homemade low explosives substances were found.
Police also recovered three computer tablets which were later found to contain 1492 indecent images of children between the ages of six and 14.